# 7 Del. Admin. Code § 5101: 7 DE Admin. Code 5101. Sediment and Stormwater Regulations

> Delaware · Regulations · In force

URL: https://www.frixlaw.com/law-library/statutes/STATE_DE_ADC_T7_5101

## Section

- **Citation:** 7 Del. Admin. Code § 5101
- **Heading:** 7 DE Admin. Code 5101. Sediment and Stormwater Regulations
- **Jurisdiction:** Delaware
- **Kind:** Regulations
- **Status:** In force
- **Text as of:** August 14, 2026
- **Source:** Compiled text
- **Location:** Delaware Administrative Code / Title 7 Natural Resources and Environmental Control / Division of Watershed Stewardship / 7 DE Admin. Code 5101

## Text

1.0 General Provisions
1.1 Findings of Fact
1.1.1 It is determined that:
1.1.1.1 Erosion and sedimentation and delivery of other nonpoint source pollutants such as nutrients through stormwater runoff continue to present serious problems throughout the State.
1.1.1.2 The removal of a stable ground cover in conjunction with the decrease in the infiltration capability of soils resulting from the creation of additional impervious areas such as roads and parking lots has accelerated the process of soil erosion and sediment deposition and nonpoint source runoff of other pollutants resulting in pollution of waters of the State. This damages domestic, agricultural, industrial, recreational, fish and wildlife and other resource uses.
1.1.1.3 Accelerated stormwater runoff increases flood flows and velocities, contributes to erosion, sedimentation and degradation of water quality, overtaxes the carrying capacity of streams and storm sewers, greatly increases the cost of public facilities in carrying and controlling stormwater, undermines floodplain management and flood control efforts in downstream communities, reduces groundwater recharge, and threatens public health, welfare and safety.
1.1.2 The regulation of stormwater runoff from land development activities will control stormwater runoff, soil erosion and nonpoint source pollution and will mitigate the adverse effects of stormwater runoff from development and will reduce threats to public health and safety.
1.2 The intent of this regulation is to enhance and extend the present erosion and sediment control activities and programs of the State for both rural and urban lands and to provide for control and management of stormwater runoff consistent with sound water and land use practices. These activities will reduce, to the maximum extent practicable, adverse effects of stormwater runoff on the water and lands of the State
is regulation is to enhance and extend the present erosion and sediment control activities and programs of the State for both rural and urban lands and to provide for control and management of stormwater runoff consistent with sound water and land use practices. These activities will reduce, to the maximum extent practicable, adverse effects of stormwater runoff on the water and lands of the State.
1.3 Applicability
1.3.1 Unless a particular activity is exempted by these regulations, a person shall not disturb land without an approved Sediment and Stormwater Management Plan from the Department or Delegated Agency. A Sediment and Stormwater Management Plan shall not be approved for a property unless it is consistent with the following items:
1.3.1.1 These regulations;
1.3.1.2 7 Del.C. Ch. 40 , relating to erosion and sediment control and stormwater management; and
1.3.1.3 7 Del.C. Ch. 60 , relating to the development, utilization, and control of the land, water, underwater and air resources of the State, including the current Delaware Construction General Permit (CGP).
1.3.2 Applicability of these regulations for plans that have been approved to comply with previous regulations shall be consistent with the following:
1.3.2.1 Plans approved to comply with previous regulations where construction has not commenced on January 1, 2014 may have the plan approval extended under the requirements of the previous regulations in subsequent three-year approval periods. Any plan approved to comply with previous regulations must commence construction no later than December 31, 2019. A plan approved to comply with previous regulations where construction has not commenced by December 31, 2019 shall expire and a new plan in compliance with these regulations shall be submitted to the Department or Delegated Agency for review and approval before commencement of construction
lan approved to comply with previous regulations must commence construction no later than December 31, 2019. A plan approved to comply with previous regulations where construction has not commenced by December 31, 2019 shall expire and a new plan in compliance with these regulations shall be submitted to the Department or Delegated Agency for review and approval before commencement of construction.
1.3.2.2 Plans approved to comply with regulations in effect prior to January 1, 2014 where construction has commenced may be extended based on the requirements in place at the time of original Plan approval. In no case shall the plan extension supersede the sunset provisions of the county or local government.
1.3.2.2.1 Project phases that have not commenced construction may be extended when the Sediment and Stormwater Management Plan for that phase has been approved with the overall plan.
1.3.2.2.2 Phases shown on a conceptual plan that are not included on the approved Sediment and Stormwater Management Plan will not be eligible for extension. A Sediment and Stormwater Management Plan must be developed for conceptual phases separately.
1.3.2.3 Commencement of construction means that the construction of the approved Plan is visible with the construction of a structure or infrastructure, including but not limited to roads, water and sewer lines, and stormwater management systems. General earth moving is not considered commencement of construction.
1.3.2.4 An individual building pad site, outparcel or future phase which was considered in an overall master plan stormwater management design and where the stormwater management facility has been constructed based upon regulations in effect prior to January 1, 2014 shall be grandfathered under the regulations in place at the time of approval of the master plan project
ommencement of construction.
1.3.2.4 An individual building pad site, outparcel or future phase which was considered in an overall master plan stormwater management design and where the stormwater management facility has been constructed based upon regulations in effect prior to January 1, 2014 shall be grandfathered under the regulations in place at the time of approval of the master plan project.
1.3.2.4.1 The Department or Delegated Agency shall verify that the proposed development of the individual building pad site, outparcel or future phase meets the original design assumptions for the stormwater management facility. If the proposed development of the individual building pad site, outparcel or future phase does not meet the original design assumptions for the regional stormwater management facility, the individual building pad site, outparcel or future phase plan must comply with these regulations.
1.3.2.4.2 The Department or Delegated Agency shall verify that the stormwater management facility functions in accordance with the approved design. If the stormwater management facility fails to function in accordance with the approved design it may be restored to its design condition as part of the proposed development of the individual building pad site, outparcel or future phase.
1.3.2.4.3 The applicant shall submit a Sediment and Stormwater Plan for the proposed development of the individual building pad site, outparcel or future phase. The Plan may be approved without additional stormwater management requirements
e approved design it may be restored to its design condition as part of the proposed development of the individual building pad site, outparcel or future phase.
1.3.2.4.3 The applicant shall submit a Sediment and Stormwater Plan for the proposed development of the individual building pad site, outparcel or future phase. The Plan may be approved without additional stormwater management requirements.
1.4 The following activities are exempt from both sediment control and stormwater management requirements established by these regulations:
1.4.1 Agricultural land management practices having a soil and water conservation plan unless the Department or Delegated Agency determines that a new or updated soil and water conservation plan is required, and the Owner or operator of the land has refused either to apply to a Conservation District for the development of a conservation plan, or to implement a conservation plan developed by a Conservation District.
1.4.2 Developments or construction that disturbs less than 5,000 square feet. Individual disturbances of less than 5,000 square feet that accumulate to exceed 5,000 square feet are not exempt and may be subject to the provisions of these regulations as determined by the Department or Delegated Agency on a case-by-case basis.
1.4.3 With written agreement of the Department, land development activities which are regulated with respect to erosion and sediment control and stormwater management under other specific State or Federal laws.
1.4.4 Commercial forest harvesting operations that meet the requirements of the Department of Agriculture under 3 Del.C. Ch. 10, Subchapter VI .
1.4.5 Permitted land application of biosolids and residuals.
1.5 Variances
1.5.1 The Department may grant a variance from any requirement of these regulations in accordance with the provisions of 7 Del.C. §6011 .
1.5.2 The Department may grant a temporary emergency variance from any requirement of these regulations in accordance with the provisions of 7 Del.C. §6012
Del.C. Ch. 10, Subchapter VI .
1.4.5 Permitted land application of biosolids and residuals.
1.5 Variances
1.5.1 The Department may grant a variance from any requirement of these regulations in accordance with the provisions of 7 Del.C. §6011 .
1.5.2 The Department may grant a temporary emergency variance from any requirement of these regulations in accordance with the provisions of 7 Del.C. §6012 .
1.5.3 The Department shall consider and decide applications for a variance from the provisions of these Regulations if all of the following are established by the applicant.
1.5.3.1 The variance sought will not be detrimental to the environment or contrary to law, or these Regulations.
1.5.3.2 Owing to special conditions or an unusual situation, a literal interpretation of these Regulations will result in hardship to the owner of the property in question.
1.5.3.3 If the variance were granted, the goals of these Regulations will be met with respect to the property in question.
1.5.4 The applicant must submit a request for a variance to the Sediment and Stormwater Program of the Department that sets forth and explains the need for the variance.
1.5.5 The Secretary or his designee shall publish his decision on the requested variance and the decision shall be effective immediately.
1.5.6 Any person whose interests are substantially affected may appeal to the Environmental Appeals Board within 15 days of publication of the Secretary’s decision.
1.5.7 The variance shall be effective from the date of its approval, not to exceed one year.
1.6 Fees and Financial Guarantees
1.6.1 Fees
1.6.1.1 The Delegated Agency has the authority to require fees to support local program implementation, including overall program management, plan review, construction review, enforcement, and maintenance responsibilities. An Owner seeking approval of a Sediment and Stormwater Management Plan shall pay a fee as prescribed by the Department or Delegated Agency
es and Financial Guarantees
1.6.1 Fees
1.6.1.1 The Delegated Agency has the authority to require fees to support local program implementation, including overall program management, plan review, construction review, enforcement, and maintenance responsibilities. An Owner seeking approval of a Sediment and Stormwater Management Plan shall pay a fee as prescribed by the Department or Delegated Agency. When the Department is the approval agency, the fees shall not exceed $80.00 per disturbed acre per project.
1.6.1.2 The establishment of fees, not involving stormwater utilities, shall be in accordance with the following items:
1.6.1.2.1 The number of needed personnel and the direct and indirect expenses associated with those personnel shall be developed by the agencies requesting delegation in a specific jurisdiction in conjunction with and with the concurrence of the Department. Those expenses will then form the basis for determining plan review, construction review and maintenance review costs.
1.6.1.2.2 The fee schedule and revisions to the fee schedule of the Delegated Agency, with the concurrence of the Department, shall be subject to applicable State or local public notice requirements. State public notice requirements shall be governed by 7 Del.C. §6004 .
1.6.2 Financial Guarantee
1.6.2.1 The Department or Delegated Agency may require and implement a financial guarantee for construction of the elements of the approved Sediment and Stormwater Management Plan.
16.2.1.1 The Owner shall submit when required to the Department or Delegated Agency a financial guarantee before the onset of construction activities
ments shall be governed by 7 Del.C. §6004 .
1.6.2 Financial Guarantee
1.6.2.1 The Department or Delegated Agency may require and implement a financial guarantee for construction of the elements of the approved Sediment and Stormwater Management Plan.
16.2.1.1 The Owner shall submit when required to the Department or Delegated Agency a financial guarantee before the onset of construction activities. The financial guarantee will ensure that action can be taken by the Department or Delegated Agency to complete required elements of the approved Sediment and Stormwater Management Plan, at the Owner's expense, should the Owner fail to initiate, complete, or maintain those measures identified in the approved Sediment and Stormwater Management Plan after being given proper notice and within a reasonable time specified by the Department or Delegated Agency.
1.6.2.1.2 The financial guarantee may be extended beyond the time period specified to cover a reasonable period of time, not less than one year, for testing the practices during storm events and for initial maintenance activities. However, the Department or Delegated Agency may adopt provisions for a partial release of the financial guarantee upon the completion of specified stages or phases of development as outlined in accepted procedures.
1.6.2.2 Following approval of the Department, the financial guarantee provisions of the Delegated Agency shall be subject to applicable State or local public notice requirements. State public notice requirements shall be governed by 7 Del.C. §6004 .
1.7 These regulations are adopted pursuant to authority conferred by and in accordance with 7 Del.C. Ch. 40 and 7 Del.C. Ch. 60 .
1.8 These regulations are not intended to interfere with, abrogate, or annul any other ordinance, rule or regulation, statute, or other provision of law
ble State or local public notice requirements. State public notice requirements shall be governed by 7 Del.C. §6004 .
1.7 These regulations are adopted pursuant to authority conferred by and in accordance with 7 Del.C. Ch. 40 and 7 Del.C. Ch. 60 .
1.8 These regulations are not intended to interfere with, abrogate, or annul any other ordinance, rule or regulation, statute, or other provision of law. The requirements of these regulations should be considered minimum requirements, and where any provision of these regulations imposes restrictions different from those imposed by any other ordinance, rule or regulation, or other provision of law, whichever provisions are more restrictive or impose higher protective standards for human health or the environment shall be considered to take precedence.
1.9 If any section, subsection, sentence, clause, phrase or portion of these regulations is for any reason held invalid or unconstitutional by any court or competent jurisdiction, such provision and such holding shall not affect the validity of the remaining portions of these regulations.
1.10 Any person who undertakes or causes to be undertaken any land disturbing activities shall ensure that soil erosion, sedimentation, increased pollutant loads and changed water flow characteristics resulting from these activities are controlled so as to minimize pollution of state waters. The requirements of these regulations are minimum standards and a person's compliance shall not relieve the person from the duty of enacting all measures necessary to minimize pollution of, or detrimental impacts to state waters.
1.11 The conduct of all hearings conducted pursuant to these regulations shall be in accordance with the relevant provisions of 7 Del.C. Ch. 60 .
1.12 The Department is responsible for the implementation and supervision of the sediment and stormwater program which is established by 7 Del.C. Ch. 40 . The program shall be administered pursuant to these regulations.
18 DE Reg. 396 (11/01/14)
22 DE Reg
.11 The conduct of all hearings conducted pursuant to these regulations shall be in accordance with the relevant provisions of 7 Del.C. Ch. 60 .
1.12 The Department is responsible for the implementation and supervision of the sediment and stormwater program which is established by 7 Del.C. Ch. 40 . The program shall be administered pursuant to these regulations.
18 DE Reg. 396 (11/01/14)
22 DE Reg. 680 (02/01/19)
2.0 Definitions
The following words and terms, when used in this regulation, shall have the following meaning unless the context clearly indicates otherwise:
“ Adequate conveyance ” means any system having sufficient capacity to transport the runoff generated during the Resource Protection Event, Conveyance Event, and Flooding Event; functions and discharges in a non-erosive manner; and does not adversely impact any offsite properties, conveyance system, stormwater facility, or State Waters.
“ Adverse impact ” means a negative impact resulting from a construction or development activity. The negative impact may include, but is not limited to, increased risk of flooding; degradation of water quality; increased sedimentation; reduced groundwater recharge; negative impacts on aquatic habitat; or threatened public health and safety.
“ Agricultural land management practices ” means those methods and procedures generally accepted by the Conservation Districts and used in the cultivation of land in order to further crop and livestock production and conservation of related soil and water resources.
“ Agricultural structure ” means a structure on a farm used solely for agricultural purposes in which the use is exclusively in connection with the production, harvesting, storage, drying, or raising of agricultural commodities, including the raising of livestock. Structures used for human habitation, public use, or a place of employment where agricultural products are processed, treated, or packaged are not considered agriculture structures for the purposes of these regulations
purposes in which the use is exclusively in connection with the production, harvesting, storage, drying, or raising of agricultural commodities, including the raising of livestock. Structures used for human habitation, public use, or a place of employment where agricultural products are processed, treated, or packaged are not considered agriculture structures for the purposes of these regulations.
“ Applicant ” means a person who has requested approval of a Sediment and Stormwater Management Plan through submittal of an application in accordance with these regulations or who has requested permission to conduct any activity subject to these regulations.
“ Best available technology ” or “ BAT ” means a level of technology based on the very best (state of the art) sediment and stormwater control and treatment measures that have been developed or are capable of being developed and that are economically achievable.
“ Best management practices ” or “ BMPs ” means schedules of activities, prohibition of practices, maintenance procedures, and other management practices or measures to prevent or reduce the discharge of pollutants. BMPs include the following, among other practices and measures: structural and non-structural controls; treatment requirements; operating procedures and practices to control site runoff.
“ Biosolids ” means solid or semi-solid material obtained from treated wastewater or animal manure.
“ Brownfield ” means any vacant, abandoned or underutilized real property the development or redevelopment of which may be hindered by the reasonably held belief that the real property may be environmentally contaminated.
“ Certified Construction Reviewer ” or “ CCR ” means those individuals, having passed a Departmental sponsored or approved training course and holding current certification, which provide on-site construction review for sediment control and stormwater management in accordance with these regulations
e hindered by the reasonably held belief that the real property may be environmentally contaminated.
“ Certified Construction Reviewer ” or “ CCR ” means those individuals, having passed a Departmental sponsored or approved training course and holding current certification, which provide on-site construction review for sediment control and stormwater management in accordance with these regulations.
“ Conservation plan ” means a customized document that outlines the use and best management practices of the natural resources on a parcel of land.
“ Conveyance event ” means the runoff event produced by a storm having an annual probability of occurrence of 10%.
“ Conveyance event volume ” or “ Cv ” means the volume of runoff generated by the Conveyance Event that is not otherwise reduced for the Resource Protection Event.
“ Dedication ” means transferring ownership of a stormwater management system to a delegated agency, public utility, municipality, stormwater utility, or private entity, along with all associated easements, escrow funds, and maintenance responsibilities.
“ Delegated Agency ” means the Conservation District, county, municipality, or State agency that has accepted responsibility in a jurisdiction for implementation of one or more elements of the Sediment and Stormwater Program within that jurisdiction.
“ Delegation ” means the acceptance of responsibility by a Conservation District, county, municipality, or State agency for the implementation of the Sediment and Stormwater Program.
“ Department ” means the Department of Natural Resources and Environmental Control.
“ Designated watershed or subwatershed ” means a watershed or subwatershed proposed by a conservation district, county, municipality, or State agency and approved by the Department. The Department may establish additional requirements due to existing water quantity or water quality problems. These requirements shall be implemented on an overall watershed or subwatershed master plan developed for water quality or water quantity protection
means a watershed or subwatershed proposed by a conservation district, county, municipality, or State agency and approved by the Department. The Department may establish additional requirements due to existing water quantity or water quality problems. These requirements shall be implemented on an overall watershed or subwatershed master plan developed for water quality or water quantity protection.
“ Detailed plan ” means a plan developed by a Licensed Professional in the State of Delaware which does not meet standard plan criteria.
“ Drainage area ” means that area contributing runoff to a single point measured in a horizontal plane, which is enclosed by a ridge line.
“ Easement ” means a grant or reservation by the Owner of land for the use of land by others for a specific purpose or purposes, and which must be included in the conveyance of land affected by the easement.
“ Effective imperviousness ”, for the purposes of these Regulations, means the equivalent percentage of a site’s impervious area that directly contributes stormwater runoff during the Resource Protection Event after all runoff reduction practices have been implemented.
“ Erosion and sediment control ” means the control of solid material, both mineral and organic, during a land disturbing activity, to prevent its transport out of the disturbed area by means of wind, water, gravity, or ice.
“ Final stabilization ” means that:
(1) All soil disturbing activities at the site have been completed and either of the two following criteria are met:
(a) A uniform (e.g. evenly distributed, without large bare areas) perennial vegetative cover with a density of 70% of the native background vegetative cover for the area has been established on all unpaved areas and areas not covered by permanent structures, or
ization ” means that:
(1) All soil disturbing activities at the site have been completed and either of the two following criteria are met:
(a) A uniform (e.g. evenly distributed, without large bare areas) perennial vegetative cover with a density of 70% of the native background vegetative cover for the area has been established on all unpaved areas and areas not covered by permanent structures, or
(b) Equivalent permanent stabilization measures (such as the use of riprap, gabions, or geotextiles) have been employed.
(2) When background native vegetation will cover less than 100% of the ground (e.g., arid areas, beaches), the 70% coverage criteria is adjusted as follows: if the native vegetation covers 50% of the ground, 70% of 50% (0.70 X 0.50 = 0.35) would require 35% total coverage for final stabilization. On a beach with no natural vegetation, no stabilization is required.
(3) For individual lots in residential construction, final stabilization means that either:
(a) The homebuilder has completed final stabilization as specified above, or
(b) The homebuilder has established temporary stabilization including perimeter controls for an individual lot prior to occupation of the home by the homeowner and informing the homeowner of the need for, and benefits of, final stabilization.
(4) For construction projects on land used for agriculture purposes (e.g., pipelines across crop or range land, staging areas for highway construction, etc.) final stabilization may be accomplished by returning the disturbed land to its preconstruction agriculture use. Areas disturbed that were not previously used for agricultural activities, such as buffer strips immediately adjacent to a “water of the United States” and areas which are not being returned to their preconstruction agricultural use must meet the final stabilization criteria (1) or (2) above.
“ Financial guarantee ” means a bond, security, letter of credit, etc
its preconstruction agriculture use. Areas disturbed that were not previously used for agricultural activities, such as buffer strips immediately adjacent to a “water of the United States” and areas which are not being returned to their preconstruction agricultural use must meet the final stabilization criteria (1) or (2) above.
“ Financial guarantee ” means a bond, security, letter of credit, etc. provided by the Owner to serve as a payment source should the Owner fail to meet the obligations and requirements of the approved Sediment and Stormwater Management Plan.
“ Flooding event ” means the runoff event produced by a storm having an annual probability of occurrence of 1.0%.
“ Flooding event volume ” or “ Fv ” means the volume of runoff generated by the Flooding Event that is not otherwise reduced for the Resource Protection Event and the Conveyance Event.
" Forest " means a biological community dominated by trees and other woody plants covering a land area of one contiguous acre or greater, and that have at least 100 trees per acre with at least 50% of those trees having a two inch or greater diameter at 4.5 feet above the ground and larger. Forest does not include orchards or other stands of trees having a curve number equivalent to "woods-grass combination". To determine whether a site meets the definition of a forest at the baseline condition of 2017, the Department or its authorized Delegated Agency may use data from various sources, including but not limited to Land Use/Land Cover data, historic and recent aerial photography, field collected data, etc.
“ Functional equivalency ” means alternative measures that are consistent with the policies, procedures, technical specifications, and advisory provisions found in the regulatory guidance documents, and which satisfy these Regulations.
“ Impervious surface ” means a surface which either prevents or retards the entry of water into the soil.
“ Infiltration ” means the passage or movement of water into the soil profile
lency ” means alternative measures that are consistent with the policies, procedures, technical specifications, and advisory provisions found in the regulatory guidance documents, and which satisfy these Regulations.
“ Impervious surface ” means a surface which either prevents or retards the entry of water into the soil.
“ Infiltration ” means the passage or movement of water into the soil profile.
" Inspection port " means an appurtenance installed within a stormwater management system to allow for observation of conditions, including water level, located below the surface.
“ Land disturbing activity ” means a land change or construction activity for residential, commercial, industrial, and institutional land development which may result in soil erosion from water or wind, or the movement of sediments or pollutants into state waters or onto lands in the State; or which may result in accelerated stormwater runoff, including, but not limited to, clearing, grading, excavating, transporting and filling of land.
“ Licensed Professional in the State of Delaware ” means a design professional licensed under 24 Del.C. Ch. 2 , 24 Del.C. Ch. 27 , or 24 Del.C. Ch. 28 .
“ Maintenance ” means the work of keeping stormwater management systems including access routes and appurtenances (grade surfaces, walls, drains, dams and structures, vegetation and other protective devices) in a safe and functioning condition as the system was designed. Routine or minor maintenance includes grass mowing and trimming, debris removal, minor sediment removal, filling eroded areas and animal burrows, and removal of trees and shrubs on embankments. Non-routine or major maintenance includes structural repair, major sediment removal and major erosion repair, and invasive aquatic vegetation removal
fe and functioning condition as the system was designed. Routine or minor maintenance includes grass mowing and trimming, debris removal, minor sediment removal, filling eroded areas and animal burrows, and removal of trees and shrubs on embankments. Non-routine or major maintenance includes structural repair, major sediment removal and major erosion repair, and invasive aquatic vegetation removal.
“ Maximum extent practicable ” or “ MEP ” means, for the purpose of these Regulations, using stormwater management measures, techniques and methods that are available and capable of being implemented while taking into consideration cost, available technology, and project site constraints.
“ Notice of Completion ” means a document issued by the Department or Delegated Agency at the end of project construction when all items and conditions of the approved Sediment and Stormwater Management Plan have been satisfied, post construction verification documents demonstrate that the stormwater management systems have been constructed in accordance with the approved Sediment and Stormwater Management Plan, and final stabilization of disturbed areas on the site has been achieved.
“ Offset ” means an alternate to strict adherence to the regulations including, but not limited to trading, banking, fee-in-lieu, or other similar program that serves as compensation when the requirements of these regulations cannot be reasonably met on an individual project basis.
“ Operation and Maintenance Plan ” means the plan which identifies required maintenance for stormwater management systems
fset ” means an alternate to strict adherence to the regulations including, but not limited to trading, banking, fee-in-lieu, or other similar program that serves as compensation when the requirements of these regulations cannot be reasonably met on an individual project basis.
“ Operation and Maintenance Plan ” means the plan which identifies required maintenance for stormwater management systems.
“ Owner ” means a person who has a legal interest in lands of this State, or who has an equitable interest in lands of this State, except when a person holds an interest in those lands as a security interest, unless through foreclosure or other action the holder has taken possession of those lands, and who undertakes, or for whose benefit, activities subject to these regulations are commenced or carried out on those lands, or the person responsible for maintenance of stormwater management systems constructed to comply with these regulations on those lands.
“ Person ” means a State or federal agency, individual, partnership, firm, association, joint venture, public or private corporation, trust, estate, commission, board, public or private institution, utility, cooperative, municipality or other political subdivision of this State, an interstate body or any other legal entity.
“ Permanent stabilization ” means the establishment of perennial vegetation by application of soil amendments, seed, and mulch in accordance with methods accepted by the Department on disturbed areas that have reached final grade in order to stabilize the soil, prevent erosion, and reduce sediment and runoff to downstream or offsite areas.
“ Post construction verification documents ” means a set of surveyed plans reflecting the as-built condition of stormwater management measures and may also include supporting computations and specifications as required by the Department or the Delegated Agency
at have reached final grade in order to stabilize the soil, prevent erosion, and reduce sediment and runoff to downstream or offsite areas.
“ Post construction verification documents ” means a set of surveyed plans reflecting the as-built condition of stormwater management measures and may also include supporting computations and specifications as required by the Department or the Delegated Agency.
" Pretreatment " means a mechanism at or before an inlet to a stormwater management practice that reduces gross pollutants and sediment from compromising the performance and to maximize the maintenance interval of the practice.
“ Redevelopment ”, including brownfield development, means a construction, alteration or improvement, including but not limited to the demolition or building of structures, filling, grading, paving, or excavating, where existing land use is residential, commercial, industrial, or institutional. Ordinary maintenance activities, remodeling of existing buildings, resurfacing of paved areas, and exterior changes or improvements are typically not considered redevelopment activities for the purposes of these regulations.
“ Resource protection event ” means the runoff event produced by a storm having an annual probability of occurrence of 99%.
“ Resource protection event volume ” or “ RPv ” means the annualized volume of runoff generated by the Resource Protection Event.
“ Responsible personnel ” means a foreman or superintendent who is in charge of on-site clearing and land disturbing activities for sediment and stormwater control associated with a construction project.
“ Runoff reduction practices ” means stormwater best management practices that reduce total runoff volume from a developed site through canopy interception, surface recharge, evaporation, rainfall harvesting, engineered infiltration, or evapotranspiration and may include practices that delay the delivery of stormwater to a surface discharge
tormwater control associated with a construction project.
“ Runoff reduction practices ” means stormwater best management practices that reduce total runoff volume from a developed site through canopy interception, surface recharge, evaporation, rainfall harvesting, engineered infiltration, or evapotranspiration and may include practices that delay the delivery of stormwater to a surface discharge.
“ Sediment ” means soils or other surficial materials transported or deposited by the action of wind, water, ice or gravity as a product of erosion.
“ Sediment and Stormwater Management Plan ” means a plan for the control of soil erosion, sedimentation, stormwater quantity, and water quality impacts resulting from a land disturbing activity, through both the construction and post construction phases of development.
“ Standard plan ” means a set of pre-defined standards or specifications for minor land disturbing activities that may preclude the need for the preparation of a detailed plan under specific conditions.
“ State waters ” means any and all waters, public or private, on the surface of the earth which are contained within, flow through or border upon the State or any portion thereof.
" Stone " means a hard non-metallic mineral building material, and for the purposes of this regulation shall be interchangeable with "gravel" and "aggregate".
“ Stormwater ” means the runoff of water from the surface of the land resulting from precipitation, or snow or ice melt.
“ Stormwater management ” means:
(a) For water quantity control, a system of vegetative, structural, and other measures that controls the volume and rate of stormwater runoff which may be caused by land disturbing activities upon the land; and
able with "gravel" and "aggregate".
“ Stormwater ” means the runoff of water from the surface of the land resulting from precipitation, or snow or ice melt.
“ Stormwater management ” means:
(a) For water quantity control, a system of vegetative, structural, and other measures that controls the volume and rate of stormwater runoff which may be caused by land disturbing activities upon the land; and
(b) For water quality control, a system of vegetative, structural, and other measures that controls adverse effects on water quality that may be caused by land disturbing activities upon the land.
" Stormwater management offset " means an alternative method of compliance to the regulations including, but not limited to, trading, banking, fee-in-lieu, or other similar program.
" Stormwater management offset district " means an organization established to administer stormwater management offsets established under Department authorization.
“ Stormwater management system ” means vegetative, structural, and other facilities or measures, singularly or in combination, as defined in Section 11.0, that provide stormwater management.
“ Stormwater utility ” means an administrative organization that has been established for the purposes of funding sediment control, stormwater management or flood control planning, design, construction, maintenance, and overall resource needs by authorized and imposed charges.
“ Temporary stabilization ” means planting quick-growing vegetation and applying anchored straw mulch or other means to stabilize the soil and prevent erosion of a disturbed area until permanent vegetation or other stabilization measures can be established.
" Third party CCR " means, for the purposes of these regulations, any individual CCR that is not an employee of the owner or a contractor of the construction activity, excluding the site designer
ing vegetation and applying anchored straw mulch or other means to stabilize the soil and prevent erosion of a disturbed area until permanent vegetation or other stabilization measures can be established.
" Third party CCR " means, for the purposes of these regulations, any individual CCR that is not an employee of the owner or a contractor of the construction activity, excluding the site designer.
“ Tidal waters ” means any water that alternately rises and falls in a predictable and measurable rhythm or cycle due to the gravitational attraction of the moon and sun and is under the regulatory authority of 7 Del.C. Ch. 72 .
“ Transfer ” means to convey responsibility for maintenance of a stormwater management system to a new Owner.
“ Variance ” means a permitted deviation from an established rule or regulation, or plan, or standard or procedure.
“ Water quality ” means those characteristics of stormwater runoff from a land disturbing activity that relate to the chemical, physical, biological, or radiological integrity of water.
“ Water quantity ” means those characteristics of stormwater runoff that relate to the rate, volume and duration of flow to downstream areas resulting from land disturbing activities.
“ Watershed ” means the drainage area contributing stormwater runoff to a single point.
“ Watershed plan ” means a comprehensive study of the activities and sources that contribute to water quality or water quantity problems and identifies the location of those problem areas within a specific watershed boundary. It also serves as a framework for how, where and what stormwater management tools will be applied to address those water quality or water quantity problems.
18 DE Reg. 396 (11/01/14)
22 DE Reg. 680 (02/01/19)
3.0 Plan Approval Procedures and Requirements
3.1 All projects requiring approval of a detailed Sediment and Stormwater Management Plan are subject to a three-step approval process. Step 1 of the plan approval process is scheduling and conducting the Project Application Meeting
be applied to address those water quality or water quantity problems.
18 DE Reg. 396 (11/01/14)
22 DE Reg. 680 (02/01/19)
3.0 Plan Approval Procedures and Requirements
3.1 All projects requiring approval of a detailed Sediment and Stormwater Management Plan are subject to a three-step approval process. Step 1 of the plan approval process is scheduling and conducting the Project Application Meeting. Step 2 of the plan approval process is submission of the Preliminary Sediment and Stormwater Management Plan. Step 3 of the plan approval process is submission of the Sediment and Stormwater Management Plan.
3.1.1 Authorization from the Department or Delegated Agency is required to proceed from the current step to the subsequent step in the plan approval process.
3.1.2 If significant changes, as determined by the Department or Delegated Agency, are proposed on the subsequent submittal from the submittal that received authorization to proceed, the Owner may be required to repeat the previous step in the plan approval process.
3.1.3 Step 2 and Step 3 of the three-step approval process may be combined as determined by the Department or Delegated Agency on a case-by-case basis. This determination may be made at the Project Application Meeting.
3.2 Project Application Meeting
3.2.1 All Owners are required to hold a Project Application Meeting with the Department or Delegated Agency, unless the requirement for a project application meeting is waived in writing by the Department or Delegated Agency as determined on a case-by-case basis.
3.2.2 Before scheduling the Project Application Meeting, the Owner shall submit a Stormwater Assessment Study (SAS) to the Department or Delegated Agency.
3.2.3 At the Project Application Meeting the Stormwater Assessment Study will be reviewed as well as potential approaches for stormwater management and opportunities to reduce runoff rates, volumes, and pollutant loads
d on a case-by-case basis.
3.2.2 Before scheduling the Project Application Meeting, the Owner shall submit a Stormwater Assessment Study (SAS) to the Department or Delegated Agency.
3.2.3 At the Project Application Meeting the Stormwater Assessment Study will be reviewed as well as potential approaches for stormwater management and opportunities to reduce runoff rates, volumes, and pollutant loads.
3.2.4 Project Application Meeting discussion and agreement items will be documented in meeting minutes prepared by the Owner or the Owner's Representative and distributed to all in attendance.
3.3 Preliminary Sediment and Stormwater Management Plan
3.3.1 The Preliminary Sediment and Stormwater Management Plan submittal shall include preliminary plans for the site, as well as the schematic erosion and sediment control plan, with supporting hydrologic and hydraulic calculations necessary for the Department or Delegated Agency to determine compliance with these regulations.
3.3.2 If significant changes are proposed on the Preliminary Sediment and Stormwater Management Plan from the plan that was discussed at the Project Application Meeting, such as a change in land use, the Owner may be required to repeat the Project Application Meeting step of the process.
3.4 Sediment and Stormwater Management Plan
3.4.1 The Sediment and Stormwater Management Plan submittal shall consist of the following elements: Construction Site Stormwater Management Plan including pollution prevention elements, Post Construction Stormwater Management Plan, final hydrologic and hydraulic computations, Operation and Maintenance Plan, and a copy of the preliminary Record Plan as required by the local land use approval agency. The plan shall also include the following notes:
3.4.1.1 The Department or Delegated Agency shall be notified in writing five days prior to commencing with construction. Failure to do so constitutes a violation of the approved Sediment and Stormwater Management Plan
tations, Operation and Maintenance Plan, and a copy of the preliminary Record Plan as required by the local land use approval agency. The plan shall also include the following notes:
3.4.1.1 The Department or Delegated Agency shall be notified in writing five days prior to commencing with construction. Failure to do so constitutes a violation of the approved Sediment and Stormwater Management Plan.
3.4.1.2 Review and or approval of the Sediment and Stormwater Management Plan shall not relieve the contractor from his or her responsibilities for compliance with the requirements of the Delaware Sediment and Stormwater Regulations, nor shall it relieve the contractor from errors or omissions in the approved plan.
3.4.1.3 Following soil disturbance or re-disturbance, permanent or temporary stabilization shall be completed for all perimeter sediment controls, soil stockpiles, and all other disturbed or graded areas on the project site within 14 calendar days unless more restrictive Federal requirements apply.
3.4.1.4 All erosion and sediment control practices shall comply with the Delaware Erosion and Sediment Control Handbook, latest edition.
3.4.1.5 At any time a dewatering operation is used, it shall be previously approved by the Agency Construction Site Reviewer for a non-erosive point of discharge, and a dewatering permit should be approved by the Department's Well Permits Branch.
3.4.1.6 Post construction verification documents shall be submitted to the Department or Delegated Agency within 60-days of stormwater management facility completion.
3.4.1.7 The Notice of Intent for Storm Water Discharges Associated with Construction Activity under a NPDES General Permit for this project is # (to be filled in once received). The permittee of record shall not be relieved of their responsibilities until a Notice of Termination has been processed by the Department.
3.4.1.8 The owner shall be familiar with and comply with all aspects of the NPDES Construction General Permit
t for Storm Water Discharges Associated with Construction Activity under a NPDES General Permit for this project is # (to be filled in once received). The permittee of record shall not be relieved of their responsibilities until a Notice of Termination has been processed by the Department.
3.4.1.8 The owner shall be familiar with and comply with all aspects of the NPDES Construction General Permit.
3.4.1.9 The contractor shall at all times protect against sediment or debris laden runoff or wind from leaving the site. Perimeter controls shall be checked daily and adjusted or repaired to fully contain and control sediment from leaving the site. Accumulated sediment shall be removed when it has reached half of the effective capacity of the control. In addition, the contractor may need to adjust or alter measures in times of adverse weather conditions, or as directed by the Agency Construction Site Reviewer.
3.4.2 If significant changes are proposed on the Sediment and Stormwater Management Plan from the Preliminary Sediment and Stormwater Management Plan, such as a change in the size or location of proposed BMPs, the Owner may be required to repeat the Preliminary Sediment and Stormwater Plan step of the process.
3.4.3 Failure by the Owner to demonstrate that the Sediment and Stormwater Management Plan meets the requirements of these regulations, as determined by the Department or Delegated Agency, shall be reason to deny approval of the Sediment and Stormwater Management Plan
or location of proposed BMPs, the Owner may be required to repeat the Preliminary Sediment and Stormwater Plan step of the process.
3.4.3 Failure by the Owner to demonstrate that the Sediment and Stormwater Management Plan meets the requirements of these regulations, as determined by the Department or Delegated Agency, shall be reason to deny approval of the Sediment and Stormwater Management Plan.
3.5 Review Procedures for Plan Submittals
3.5.1 The Department or Delegated Agency shall have 30 calendar days from receipt of either the Preliminary Sediment and Stormwater Management Plan or final Sediment and Stormwater Management Plan to complete the review and have either the approval or review comments transmitted to the Owner, unless the 30-calendar day period cannot be met, in which case the Department or Delegated Agency shall notify the Owner in writing of the reasons for delay, and an expected time period not to exceed an additional 30 calendar days, for when that review will be completed.
3.5.2 The Department or Delegated Agency shall have the right to reject an incomplete application at any time during the 30-calendar day review period. If an application is rejected for incompleteness, the Owner will be informed in writing of the information necessary to complete the application.
3.5.3 In cases where modifications are required to approve the plan, the Department or Delegated Agency shall have an additional 30 calendar days to review the revised plan from the initial and any subsequent resubmission dates.
3.5.4 The sediment and stormwater management plan shall not be considered approved without the inclusion of an original approval stamp on the plans with signature and date by the plan approval agency. If the plan is approved, a minimum of one (1) copy bearing the signed approval stamp shall be returned to the Owner or Owner’s agent. If the plan is not approved, the Owner shall be notified in writing of the reasons
t and stormwater management plan shall not be considered approved without the inclusion of an original approval stamp on the plans with signature and date by the plan approval agency. If the plan is approved, a minimum of one (1) copy bearing the signed approval stamp shall be returned to the Owner or Owner’s agent. If the plan is not approved, the Owner shall be notified in writing of the reasons.
3.5.5 No changes shall be made to an approved plan without review and written approval by the Department or Delegated Agency. The Department or Delegated Agency may request additional data with a plan amendment as may be necessary for a complete review of the plan and to ensure that changes to the plan will comply with the requirements of these regulations.
3.6 Expiration of Plan Approval
3.6.1 Approved plans remain valid for five years from the date of an approval, unless specifically extended by the Department or Delegated Agency. The basis for extension may include, but is not limited to, the following items:
3.6.1.1 Failure to initiate the approved project for reasons acceptable to the Department or Delegated Agency such as funding or other agency permit delays; or
3.6.1.2 Time duration for a type of activity that typically exceeds five years.
3.6.2 The Department or Delegated Agency may extend plan approval following a written request for extension providing justification for the extension request. Plan approval extension may be granted no more than 90 days before plan expiration, and will be granted for a maximum extension of an additional five years. In no case shall the plan extension supersede the sunset provisions of the county or local government.
3.6.3 Plan extension requests for projects that have not commenced construction shall be granted for a maximum of one additional five-year period
approval extension may be granted no more than 90 days before plan expiration, and will be granted for a maximum extension of an additional five years. In no case shall the plan extension supersede the sunset provisions of the county or local government.
3.6.3 Plan extension requests for projects that have not commenced construction shall be granted for a maximum of one additional five-year period.
3.6.4 Plan extension requests for projects that have commenced and have been actively under construction within the latest approval or extension period will not be limited in the number of extensions that may be approved.
3.7 Standard Plans
3.7.1 In the event that a project meets the Standard Plan Applicability Criteria for the project type, that project has the option to comply with Standard Plan Conditions for the project type in lieu of developing a detailed Sediment and Stormwater Management Plan for the project. Project types for which Standard Plan Applicability Criteria has been developed include:
3.7.1.1 residential construction less than 1.0 acre disturbed;
3.7.1.2 residential construction greater than or equal to 1.0 acre disturbed;
3.7.1.3 non-residential construction less than 1.0 acre disturbed;
3.7.1.4 tax ditch maintenance;
3.7.1.5 minor linear utility disturbances;
3.7.1.6 stormwater facility maintenance;
3.7.1.7 agricultural structure construction;
3.7.1.8 poultry house construction;
3.7.1.9 demolition;
3.7.1.10 BMP construction or retrofit;
3.7.1.11 minor bridge and culvert construction; and
3.7.1.12 sidewalk, trail or other linear impervious surfaces.
3.7.2 All standard plans shall contain standard conditions for construction site stormwater management and may contain standard conditions for post construction stormwater management.
3.7.3 The inclusion of an activity into the standard plan classification does not exclude that activity from the requirements of 7 Del.C. Ch. 40 . Rather, the standard plan precludes that activity from the necessity of a detailed plan review for a qualifying project
nditions for construction site stormwater management and may contain standard conditions for post construction stormwater management.
3.7.3 The inclusion of an activity into the standard plan classification does not exclude that activity from the requirements of 7 Del.C. Ch. 40 . Rather, the standard plan precludes that activity from the necessity of a detailed plan review for a qualifying project.
3.7.4 Failure to implement control practices pursuant to conditions included in the standard plan may necessitate appropriate enforcement action as provided in 7 Del.C. Ch. 40 and these regulations.
3.7.5 A detailed plan may be required for a site that would otherwise meet standard plan criteria but does not meet the intent of the regulations as determined by the Department or Delegated Agency on a case-by-case basis. The Department or Delegated Agency may require a detailed plan prior to approval or at any time during construction.
3.7.6 Parcels that have previously received approval under a Standard Plan may not be eligible for a Standard Plan in the future, as determined by the approval agency on a case-by-case basis.
3.7.7 A project that does not meet all Standard Plan Applicability Criteria but does meet the intent of the regulations may be considered for approval under the Standard Plan as determined by the Department or Delegated Agency on a case-by-case basis.
3.7.8 Approval of a standard plan does not relieve the applicant from complying with any and all federal, state, county, or municipal laws and regulations.
3.7.9 Construction projects exceeding 1.0 acre of total disturbance require submittal of a Notice of Intent (NOI) for Stormwater Discharges Associated with Construction Activity. A plan fulfilling Stormwater Pollution Prevention Plan (SWPPP) requirements must be developed to obtain general permit coverage for Stormwater Discharges Associated with Construction Activity.
3.7.10 Construction site stormwater management best management practices shall be used throughout construction
tal of a Notice of Intent (NOI) for Stormwater Discharges Associated with Construction Activity. A plan fulfilling Stormwater Pollution Prevention Plan (SWPPP) requirements must be developed to obtain general permit coverage for Stormwater Discharges Associated with Construction Activity.
3.7.10 Construction site stormwater management best management practices shall be used throughout construction.
3.7.11 Residential construction less than 1.0 acre disturbed
3.7.11.1 For the purposes of standard plan criteria for residential construction less than 1.0 acre disturbed, residential construction means residential and auxiliary structures such as detached garages, sheds, pole barns, and other structures that create additional imperviousness.
3.7.11.2 Applicability criteria:
3.7.11.2.1 The total land disturbance will not exceed 1.0 acre on any individual lot within the proposed project.
3.7.11.2.2 The proposed construction is for residential development that does not create common lands, common open space, or a public street.
3.7.11.3 Conditions. Standard Detail and Specification DE-ESC-3.7.1 ESC For Minor Development will be followed during construction.
3.7.12 Residential construction greater than or equal to 1.0 acre disturbed
3.7.12.1 For the purposes of standard plan criteria for residential construction greater than or equal to 1.0 acre disturbed, residential construction means single family residence and auxiliary structures such as detached garages, sheds, pole barns, accessory dwelling units, and other structures that create additional imperviousness.
3.7.12.2 Applicability criteria:
3.7.12.2.1 The proposed construction is for residential construction that does not create common lands, common open space, or a public street.
3.7.12.2.2 The total land disturbance will not exceed 5.0 acres on any individual lot within the proposed project
ages, sheds, pole barns, accessory dwelling units, and other structures that create additional imperviousness.
3.7.12.2 Applicability criteria:
3.7.12.2.1 The proposed construction is for residential construction that does not create common lands, common open space, or a public street.
3.7.12.2.2 The total land disturbance will not exceed 5.0 acres on any individual lot within the proposed project.
3.7.12.2.3 One of the following will be met on any individual lot:
3.7.12.2.3.1 Clearing of forest areas will not exceed 1.0 acre, or
3.7.12.2.3.2 Equivalent forest area will be retained on the parcel for the portion of the forest clearing that exceeds 1.0 acre.
3.7.12.3 Conditions:
3.7.12.3.1 Standard nutrient management plan recommendations will be followed for the project, during construction and throughout the life of the project.
3.7.12.3.1.1 Application of lawn nutrients will be based upon the recommendations of a soil test.
3.7.12.3.1.2 Nutrients will be applied only to turf areas, not impervious surfaces.
3.7.12.3.1.3 Nutrients will not be applied directly before a runoff event.
3.7.12.3.2 Discharges from rooftops will be disconnected to the maximum extent practicable using a method approved by the Department or Delegated Agency. For example:
3.7.12.3.2.1 Individual downspouts that discharge to lawn, landscape area, or preserved open space or forested area.
3.7.12.3.2.2 Discharges from downspouts can be collected in rain barrels or cisterns for reuse.
3.7.12.3.3 Driveways, sidewalks, patios, and other impervious surfaces will be graded to sheet flow to lawn or other pervious areas to the maximum extent practicable.
3.7.12.3.4 Standard Detail and Specification DE-ESC-3.7.1 ESC For Minor Development will be followed during construction.
3.7.13 Non-residential construction less than 1.0 acre disturbed
3.7.13.1 Applicability criteria:
3.7.13.1.1 The disturbed area for construction of the improvements will not exceed 1.0 acre
graded to sheet flow to lawn or other pervious areas to the maximum extent practicable.
3.7.12.3.4 Standard Detail and Specification DE-ESC-3.7.1 ESC For Minor Development will be followed during construction.
3.7.13 Non-residential construction less than 1.0 acre disturbed
3.7.13.1 Applicability criteria:
3.7.13.1.1 The disturbed area for construction of the improvements will not exceed 1.0 acre.
3.7.13.1.2 Within the disturbed area, the pre-development land use is not classified as forest.
3.7.13.1.3 For project site locations within an area previously managed for stormwater quantity and quality under an approved Sediment and Stormwater Plan, the post construction condition meets the original stormwater design criteria.
3.7.13.1.4 For project site locations within an area previously unmanaged for stormwater quantity and quality under an approved Sediment and Stormwater Plan, one of the following is met:
3.7.13.1.4.1 Comparison of the existing parcel curved number (CN) based upon the Department’s 2017 aerial photography to the proposed CN for the parcel after non-residential construction results in less than one whole number change in the CN, or
3.7.13.1.4.2 No new impervious area is proposed as a result of construction.
3.7.13.2 Conditions:
3.7.13.2.1 Discharges from rooftops will be disconnected to the maximum extent practicable using one of the following methods or another method approved by the Department or Delegated Agency:
3.7.13.2.1.1 Individual downspouts will discharge to lawn or landscape area.
3.7.13.2.1.2 Discharges from downspouts will be collected to discharge to a rain garden.
3.7.13.2.1.3 Discharges from downspouts will be collected in rain barrels or cisterns for reuse.
3.7.13.2.2 Driveways, sidewalks, patios, and other impervious surfaces will be graded to sheet flow to lawn or other pervious areas to the maximum extent practicable
spouts will discharge to lawn or landscape area.
3.7.13.2.1.2 Discharges from downspouts will be collected to discharge to a rain garden.
3.7.13.2.1.3 Discharges from downspouts will be collected in rain barrels or cisterns for reuse.
3.7.13.2.2 Driveways, sidewalks, patios, and other impervious surfaces will be graded to sheet flow to lawn or other pervious areas to the maximum extent practicable.
3.7.13.2.3 Unless waived in writing by the Department or Delegated Agency a construction site stormwater management plan in accordance with Department or Delegated Agency guidance for this Standard Plan shall be followed.
3.7.14 Tax Ditch Maintenance
3.7.14.1 Applicability criteria. Land disturbance is for maintenance of a recorded tax ditch having a design on file with the Department.
3.7.14.2 Conditions:
3.7.14.2.1 Construction will follow "Principles and Guidelines for Planning, Constructing, and Maintaining Drainage Ditches in the State of Delaware", June 1995.
3.7.14.2.2 Following maintenance the tax ditch elevations will be returned to design elevations.
3.7.15 Minor Linear Utility Disturbance
3.7.15.1 Applicability criteria.
3.7.15.1.1 Disturbance will be for linear utility construction, having a maximum width of disturbance of 40 feet.
3.7.15.1.2 One of the following is met:
3.7.15.1.2.1 Total disturbance is 1.0 acre or less; or
3.7.15.1.2.2 Total disturbance is 5.0 acres or less, and
3.7.15.1.2.2.1 No greater than 1.0 acre will be disturbed at any time throughout the course of construction, and
3.7.15.1.2.2.2 Land cover will be restored to the pre-construction hydrologic condition. In the case of forest clearing, land cover will be restored to an equivalent meadow condition.
3.7.15.2 Conditions:
3.7.15.2.1 Stabilization with seed and mulch or seed and stabilization matting will occur daily so that no greater than one acre will be disturbed at any one time
the course of construction, and
3.7.15.1.2.2.2 Land cover will be restored to the pre-construction hydrologic condition. In the case of forest clearing, land cover will be restored to an equivalent meadow condition.
3.7.15.2 Conditions:
3.7.15.2.1 Stabilization with seed and mulch or seed and stabilization matting will occur daily so that no greater than one acre will be disturbed at any one time.
3.7.15.2.2 Construction through sensitive areas, including stream and wetland crossings, will be accomplished through directional drilling, with land disturbance happening outside of the sensitive area.
3.7.16 Stormwater Facility Maintenance
3.7.16.1 Applicability criteria. Land disturbance is for maintenance of a stormwater management facility having a design on file with the Department or Delegated Agency.
3.7.16.2 Conditions:
3.7.16.2.1 Construction will follow an Operation and Maintenance Plan in place for the stormwater management facility if one exists.
3.7.16.2.2 Following maintenance the stormwater management facility elevations will be returned to design elevations.
3.7.17 Agricultural Structure Construction
3.7.17.1 Applicability criteria.
3.7.17.1.1 Construction is for an agricultural structure as defined in Section 2.0 of these regulations.
3.7.17.1.2 The total land disturbance will not exceed 5.0 acres.
3.7.17.1.3 The pre-construction land use at the location of the agricultural structure is historically agricultural use (farmstead, crop field, pasture). Within the disturbed area, the pre- development land use is not classified as forest. If any portion of the pre-construction land use is forest, a detailed plan is required.
3.7.17.1.4 The proposed impervious area as a result of construction of an agricultural structure is less than 10% of the watershed area to the point of discharge from the parcel.
3.7.17.2 Conditions:
3.7.17.2.1 Nutrient management plan recommendations will be followed for the project, during construction and throughout the life of the project
uction land use is forest, a detailed plan is required.
3.7.17.1.4 The proposed impervious area as a result of construction of an agricultural structure is less than 10% of the watershed area to the point of discharge from the parcel.
3.7.17.2 Conditions:
3.7.17.2.1 Nutrient management plan recommendations will be followed for the project, during construction and throughout the life of the project.
3.7.17.2.2 Discharges from rooftops will be disconnected from impervious surfaces to the maximum extent practicable. Downspouts, if applicable, will discharge to a stabilized area, such as grass or gravel.
3.7.17.2.3 Impervious surfaces, including compacted gravel roadways, will be graded to sheet flow to pervious areas to the maximum extent practicable.
3.7.18 Poultry House Construction
3.7.18.1 Applicability criteria.
3.7.18.1.1 Construction is for one or more poultry houses and associated structures including generator and pump structures, composter structures and manure storage structures. Other agricultural structures shall comply with subsection 3.7.17.
3.7.18.1.2 Poultry house layout, including the general dimensions of structures, roadways and loading areas, as well as spacing between structures will adhere to Department or Delegated Agency guidance for this Standard Plan.
3.7.18.2 Conditions.
3.7.18.2.1 Nutrient management plan recommendations will be followed for the project, during construction and throughout the life of the project.
3.7.18.2.2 To the maximum extent practicable, runoff from impervious surfaces including roof, roadways, and loading areas will be conveyed to an ephemeral wetland forebay. Ephemeral wetland forebay volume calculations based on Department or Delegated Agency guidance for this Standard Plan will be submitted.
3.7.18.2.3 A detention basin will be provided to manage the runoff from the Conveyance (Cv) and Flooding (Fv) events
extent practicable, runoff from impervious surfaces including roof, roadways, and loading areas will be conveyed to an ephemeral wetland forebay. Ephemeral wetland forebay volume calculations based on Department or Delegated Agency guidance for this Standard Plan will be submitted.
3.7.18.2.3 A detention basin will be provided to manage the runoff from the Conveyance (Cv) and Flooding (Fv) events. For poultry houses constructed where there is no forest clearing, the volume of the detention basin may be included in the ephemeral wetland forebay to make one detention structure. Detention basin volume calculations based on Department or Delegated Agency guidance for this Standard Plan will be submitted.
3.7.18.2.4 Vegetated stabilization will be completed in accordance with Department or Delegated Agency guidance for this Standard Plan.
3.7.19 Demolition
3.7.19.1 Applicability criteria.
3.7.19.1.1 Land disturbance is for demolition and removal of a structure, building foundation, building slab, roadway, driveway, parking lot, sidewalk, or other amenity resulting in exposed soil, including access and staging for demolition activities.
3.7.19.1.2 Total disturbance is 5.0 acres or less, and no greater than 1.0 acre will be disturbed at any time throughout the course of construction.
3.7.19.1.3 Disturbed land will be restored to a stabilized surface. No additional impervious surfaces shall be created as part of the demolition project.
3.7.19.2 Conditions. Stabilization with seed and mulch or seed and stabilization matting will occur within 14 days of completion of demolition.
3.7.20 BMP Construction and Retrofit
3.7.20.1 Applicability criteria:
3.7.20.1.1 The construction will provide either:
3.7.20.1.1.1 RPv, Cv or Fv reduction by implementing Post Construction Stormwater BMP, retrofitting a degraded BMP, or creating a floodplain;
3.7.20.1.1.2 Stabilization of an eroding area.
3.7.20.1.2 The total land disturbance will not exceed 5.0 acres
of completion of demolition.
3.7.20 BMP Construction and Retrofit
3.7.20.1 Applicability criteria:
3.7.20.1.1 The construction will provide either:
3.7.20.1.1.1 RPv, Cv or Fv reduction by implementing Post Construction Stormwater BMP, retrofitting a degraded BMP, or creating a floodplain;
3.7.20.1.1.2 Stabilization of an eroding area.
3.7.20.1.2 The total land disturbance will not exceed 5.0 acres.
3.7.20.1.3 Within the disturbed area, the pre-development land use is not classified as forest.
3.7.20.1.4 The total impervious area proposed (roof, driveway, sidewalks, auxiliary structures, etc.) will not exceed the lesser of 7,500 square feet or 15% of the disturbed area.
3.7.20.2 Conditions:
3.7.20.2.1 The area must be returned grassed or vegetated condition (excluding permeable pavement installation and the allowable impervious areas), after construction and throughout the life of the project.
3.7.20.2.2 Discharges from added impervious areas will be disconnected to the maximum extent practicable using one of the following methods or another method approved by the Department or Delegated Agency:
3.7.20.2.2.1 Impervious areas will discharge to grassed or vegetated area.
3.7.20.2.2.2 Discharges from impervious area will be collected to discharge to a rain garden.
3.7.20.2.2.3 Discharges from impervious areas will be collected in rain barrels or cisterns for reuse.
3.7.21 Minor Bridge and Culvert Construction
3.7.21.1 Applicability criteria:
3.7.21.1.1 The disturbed area for construction of the improvements will not exceed 1.0 acre.
3.7.21.1.2 The net increase in impervious area will not exceed 5,000 square feet.
3.7.21.1.3 Land cover will be restored to the pre-construction hydrologic condition or better.
3.7.21.2 Conditions:
3.7.21.2.1 Impervious surfaces will be graded to sheet flow to pervious areas to the maximum extent
practicable.
3.7.21.2.2 All non-impervious disturbed area will be vegetated to original or better condition
1.1.2 The net increase in impervious area will not exceed 5,000 square feet.
3.7.21.1.3 Land cover will be restored to the pre-construction hydrologic condition or better.
3.7.21.2 Conditions:
3.7.21.2.1 Impervious surfaces will be graded to sheet flow to pervious areas to the maximum extent
practicable.
3.7.21.2.2 All non-impervious disturbed area will be vegetated to original or better condition.
3.7.22 Sidewalk, Trail, or Other Linear Impervious Surfaces
3.7.22.1 Applicability criteria:
3.7.22.1.1 Disturbance will be for construction of a sidewalk, trail or other linear impervious surface with total disturbance not to exceed 5.0 acres.
3.7.22.1.2 No greater than 1.0 acre disturbed at any one time throughout the course of construction.
3.7.22.1.3 Within the disturbed area, the pre-development land use is not classified as forest.
3.7.22.1.4 For project site locations within an area previously managed for stormwater quantity and quality under an approved Sediment and Stormwater Plan, the post construction condition meets the original stormwater design criteria.
3.7.22.1.5 For project site locations within an area previously unmanaged for stormwater quantity and quality under an approved Sediment and Stormwater Plan, one of the following is met:
3.7.22.1.5.1 Comparison of the existing parcel curve number (CN) based upon the Department’s 2017 aerial photography to the proposed CN for the parcel after non-residential construction results in less than one whole number change in the CN, or
3.7.22.1.5.2 No new impervious area is proposed as a result of construction.
3.7.22.2 Conditions:
3.7.22.2.1 Impervious surfaces will be graded to sheet flow to lawn or other pervious areas to the maximum extent practicable.
3.7.22.2.2 Stabilization of exposed soil areas with seed and mulch or seed and stabilization matting will occur daily so that no greater than one acre will be disturbed at any one time
5.2 No new impervious area is proposed as a result of construction.
3.7.22.2 Conditions:
3.7.22.2.1 Impervious surfaces will be graded to sheet flow to lawn or other pervious areas to the maximum extent practicable.
3.7.22.2.2 Stabilization of exposed soil areas with seed and mulch or seed and stabilization matting will occur daily so that no greater than one acre will be disturbed at any one time.
3.8 Plan Certifications
3.8.1 All detailed plans submitted for review shall be prepared, signed, dated, and sealed by a Licensed Professional in the State of Delaware. It is the obligation of the Licensed Professional in the State of Delaware to ensure that the design of construction site stormwater management best management practices (BMPs) and post construction stormwater management systems meet the requirements in these regulations.
3.8.2 All Sediment and Stormwater Management Plans submitted for approval shall contain certification by the Owner stating that clearing, grading, construction, and development will be accomplished pursuant to the plan.
3.8.3 All Sediment and Stormwater Management Plans for projects having a land disturbance greater than or equal to one acre shall contain a certification by the Owner stating that responsible personnel involved in the land disturbance will have attended and successfully completed the Departmental-sponsored Contractor Training Program before initiation of the project.
3.8.4 All Sediment and Stormwater Management Plans shall contain certification by the Owner granting the right of either the Department or Delegated Agency or both to conduct on-site reviews.
3.9 Before project completion the Owner shall submit a final post construction stormwater management Operation and Maintenance Plan for the entire stormwater management system. Operation and Maintenance Plans remain valid for the life of the stormwater management system
in certification by the Owner granting the right of either the Department or Delegated Agency or both to conduct on-site reviews.
3.9 Before project completion the Owner shall submit a final post construction stormwater management Operation and Maintenance Plan for the entire stormwater management system. Operation and Maintenance Plans remain valid for the life of the stormwater management system.
3.10 Post construction verification documents shall be submitted to the Department or Delegated Agency within 60 calendar days of completion for stormwater management systems. The post construction verification documents shall compare the designed and constructed elements of the stormwater management system, and bear the seal of a Licensed Professional in the State of Delaware. A final construction review and approval by the Department or Delegated Agency is required before a financial guarantee shall be released, and before a Notice of Completion may be issued.
18 DE Reg. 396 (11/01/14)
22 DE Reg. 680 (02/01/19)
4.0 Performance Criteria for Construction Site Stormwater Management
4.1 All construction site stormwater management practices shall be consistent with the current version of the Delaware Erosion and Sediment Control (ESC) Handbook. A proposal to use temporary control measures that are not included in the current version of the Delaware ESC Handbook shall be submitted to the Department for approval. The proposal shall be accompanied by supporting documentation as necessary to determine appropriateness of the proposed temporary control measure for the proposed use.
4.2 A sequence of construction shall be provided on plans describing the relationship between the implementation and maintenance of erosion and sediment controls, including permanent and temporary stabilization and the various stages or phases of earth disturbance and construction.
4.3 Best available technology (BAT) shall be employed to manage turbid discharges in accordance with requirements of 7 Del.C. Ch
nce of construction shall be provided on plans describing the relationship between the implementation and maintenance of erosion and sediment controls, including permanent and temporary stabilization and the various stages or phases of earth disturbance and construction.
4.3 Best available technology (BAT) shall be employed to manage turbid discharges in accordance with requirements of 7 Del.C. Ch. 60 , and the current Delaware Construction General Permit (CGP).
4.4 Limits on Land Disturbance
4.4.1 Unless an exception is approved on a case by case basis for a specific type of activity by the appropriate plan approval agency, not more than 20 acres may be disturbed at any one time. This will necessitate the phasing of construction on sites in excess of 20 acres to minimize areas exposed of ground cover and reduce erosion rates. Disturbance of a second 20 acre section may not proceed until temporary or permanent stabilization of the first 20 acre section is accomplished.
4.4.2 If approved by the Department or Delegated Agency sites may disturb greater than 20 acres. Sites having disturbed areas greater than 20 acres shall comply with the following:
4.4.2.1 Construction site stormwater management BMPs shall be designed for disturbed drainage areas greater than 20 acres and shall have supporting design computations, including but not limited to storage, conveyance, stability, and treatment capabilities based on the 2-year storm event with bare earth conditions.
4.4.2.1.1 Conveyance measures shall be designed to have adequate capacity for conveyance of flow in a non-erosive manner.
4.4.2.1.2 Storage practices shall be designed to adequately contain the volume of the design storm event.
4.4.2.2 Reasonable precautions shall be taken to control dust at all times. Dust shall be controlled by applying adequate amounts of water, chemical stabilizer, or other effective dust suppressant
sures shall be designed to have adequate capacity for conveyance of flow in a non-erosive manner.
4.4.2.1.2 Storage practices shall be designed to adequately contain the volume of the design storm event.
4.4.2.2 Reasonable precautions shall be taken to control dust at all times. Dust shall be controlled by applying adequate amounts of water, chemical stabilizer, or other effective dust suppressant.
4.4.3 All plans shall include a limit of disturbance line (L.O.D.) establishing the maximum necessary extent of land disturbance required to implement and accomplish the permitted site construction for land disturbing activities subject to these Regulations.
4.5 Stabilization
4.5.1 Following soil disturbance or re-disturbance, Permanent or Temporary Stabilization shall be completed for perimeter sediment controls, topsoil stockpiles, and all other disturbed or graded areas on the project site within 14 calendar days unless more restrictive Federal requirements apply.
4.5.2 Documentation of soil testing and materials used for temporary or permanent stabilization including but not limited to soil test results, seed tags, soil amendment tags, etc. shall be provided to the Department or Delegated Agency to verify that the permanent or temporary stabilization has been completed in accordance with the approved plan.
4.5.3 The Department or Delegated Agency may require additional soil testing and reapplication of permanent or temporary stabilization in accordance with the specifications in the Delaware Erosion and Sediment Control Handbook, or alternative measures that provide functional equivalency.
4.5.4 Release of either a financial guarantee or issuance of Notice of Completion or both shall not occur until final stabilization of exposed areas is achieved.
18 DE Reg. 396 (11/01/14)
22 DE Reg
lication of permanent or temporary stabilization in accordance with the specifications in the Delaware Erosion and Sediment Control Handbook, or alternative measures that provide functional equivalency.
4.5.4 Release of either a financial guarantee or issuance of Notice of Completion or both shall not occur until final stabilization of exposed areas is achieved.
18 DE Reg. 396 (11/01/14)
22 DE Reg. 680 (02/01/19)
5.0 Performance Criteria for Post Construction Stormwater Management
5.1 Post construction stormwater management plans shall be designed in accordance with the following:
5.1.1 Stormwater management designs shall reduce runoff, mimic natural watershed hydrologic processes, and cause no adverse impact to property. This shall be accomplished by treating runoff at the source, disconnecting impervious surfaces, preserving or enhancing natural flow paths and vegetative cover, conserving or enhancing natural open spaces and riparian areas, and other measures that simulate natural watershed hydrologic processes.
5.1.2 Land disturbance including but not limited to residential, commercial, institutional, agricultural structures, or industrial developments shall apply these stormwater management criteria to land development as a whole. Smaller sites, such as individual residential lots in new subdivisions that are part of a larger, common plan of development or sale shall be subject to these requirements as part of that larger plan.
5.1.3 No portion of a stormwater system that is owned and maintained by a joint ownership such as a homeowner’s association or maintenance corporation in a residential development shall be located on private property, except for those areas designated as common areas, community open space, community-owned property, or jointly owned property. Shared facilities located on private property shall be within a recorded easement
rmwater system that is owned and maintained by a joint ownership such as a homeowner’s association or maintenance corporation in a residential development shall be located on private property, except for those areas designated as common areas, community open space, community-owned property, or jointly owned property. Shared facilities located on private property shall be within a recorded easement. A stormwater system owned by a single Owner, as in the case of a commercial, institutional or industrial development, may be located on that Owner’s private property.
5.1.4 If runoff from a land development will flow to a permitted or non-permitted municipal separate storm sewer system (MS4) or other publicly maintained drainage infrastructure, the land development applicant shall notify the system’s owner of the intent to discharge into the system before plan approval. The Department, Delegated Agency, or system’s owner may require the land development applicant to demonstrate that the system has adequate conveyance.
5.1.5 All applications that propose to use infiltration or natural recharge shall include a soils investigation in accordance with subsection 12.1 of these regulations to determine the appropriate design criteria.
5.1.6 Water quality and water quantity management shall be provided in accordance with the requirements set forth in this section unless the proposed project is limited to reconstruction of existing paved areas, re-grading and replacement of existing pervious areas, or rebuilding or repairing of structures damaged by fire, flood, wind, or other natural disaster and where the disturbed area will return to the original hydrologic condition and land cover at the conclusion of the project.
5.1.7 Post construction stormwater management BMPs shall meet the following requirements:
5.1.7.1 Post construction stormwater management BMPs shall be designed and constructed in accordance with all applicable subsections of Section 11.0 and Section 12.0 of these regulations
where the disturbed area will return to the original hydrologic condition and land cover at the conclusion of the project.
5.1.7 Post construction stormwater management BMPs shall meet the following requirements:
5.1.7.1 Post construction stormwater management BMPs shall be designed and constructed in accordance with all applicable subsections of Section 11.0 and Section 12.0 of these regulations.
5.1.7.2 A single BMP may require compliance with more than one subsection of Section 11.0 based upon its function and design.
5.2 Resource Protection Event Criteria
5.2.1 The Resource Protection Event criteria provide runoff management measures to reduce the volume of stormwater runoff generated on a site, recharge groundwater, minimize impacts to downstream channels from runoff leaving the site, and reduce pollutant loads discharged into receiving waters.
5.2.2 The Resource Protection Event Volume (RPv) is the post-development annualized volume of runoff produced by the storm having a ninety-nine percent (99%) probability of occurrence, or the 1-year, 24-hour rainfall event. It is equal to the runoff volume generated by a 2.7" storm event.
5.2.3 Compliance with subsection 5.2 shall be accomplished to the maximum extent practicable through the following provisions:
5.2.3.1 Treatment of runoff from the RPv event with Best Management Practices (BMPs) as set forth in Section 11.0 shall meet the following requirements:
5.2.3.1.1 For forested areas within the site Limit of Disturbance (LOD), the treatment volume shall be the difference in the post-developed condition and an equivalent wooded condition, up to a maximum of 1" of runoff.
5.2.3.1.2 For non-forested areas within the site LOD, the treatment volume shall be the difference in the post-developed condition and an equivalent grassed open space condition, up to a maximum of 1" of runoff.
5.2.3.1.3 The treatment volume for existing impervious areas within the site LOD shall meet the requirements for redevelopment in accordance with subsection 5.6 of these regulations
unoff.
5.2.3.1.2 For non-forested areas within the site LOD, the treatment volume shall be the difference in the post-developed condition and an equivalent grassed open space condition, up to a maximum of 1" of runoff.
5.2.3.1.3 The treatment volume for existing impervious areas within the site LOD shall meet the requirements for redevelopment in accordance with subsection 5.6 of these regulations.
5.2.3.1.4 BMPs that treat more than 1" of runoff may be used to over-manage LOD subareas within a site that are untreated or partially treated.
5.2.3.1.5 Any additional runoff volume treated by BMPs in excess of that necessary to achieve site compliance in accordance with subsection 5.2 may be used as a credit in accordance with Section 13.0 Offset Provisions.
5.2.3.2 If additional measures are necessary to manage the remainder of runoff from the RPv to achieve the pre-development runoff rate from the RPv, then additional BMPs shall be utilized to achieve the pre-development runoff rate.
5.2.3.3 An offset shall be provided in accordance with Section 13.0 of these regulations for any portion of the RPv that does not meet the requirements of subsection 5.2.3.1 above.
5.2.4 Projects that qualify for and meet standard plan criteria in accordance with subsection 3.7 of these regulations shall be considered in compliance with the Resource Protection Event criteria.
5.3 Conveyance Event Criteria
5.3.1 The Conveyance Event criteria provide runoff management measures to minimize impacts to downstream properties, channels, and structures by optimizing watershed conveyance and hydrograph timing.
5.3.2 The Conveyance Event Volume (Cv) is the volume of runoff produced by the post-development storm having a ten percent (10%) annual probability of occurrence, or the 10-year, 24-hour rainfall event
.3.1 The Conveyance Event criteria provide runoff management measures to minimize impacts to downstream properties, channels, and structures by optimizing watershed conveyance and hydrograph timing.
5.3.2 The Conveyance Event Volume (Cv) is the volume of runoff produced by the post-development storm having a ten percent (10%) annual probability of occurrence, or the 10-year, 24-hour rainfall event.
5.3.3 Compliance with subsection 5.3 shall be accomplished through the following provisions:
5.3.3.1 The Cv shall be managed using BMPs as set forth in Section 11.0 such that there is no adverse impact by limiting the increase in the downstream post-developed water surface elevation to no more than 0.05 feet; or
5.3.3.2 Improving the existing downstream conveyance system to the point where the downstream condition meets the "no adverse impact" criteria of subsection 5.3.3.1; but no farther than the point where the LOD is less than 10% of the contributing drainage area; or
5.3.3.3 Provisions will be made or exist for a non-erosive conveyance system to tidal waters by either a closed drainage system or by open channel flow that has adequate conveyance for the Cv; or
5.3.3.4 Demonstration that the location of a project within a watershed would aggravate flooding or channel erosion by the imposition of peak control requirements, as evidenced by a downstream analysis that shows the inflection point of the site hydrograph occurs prior to and is less than the peak of the upstream hydrograph; or
5.3.3.5 The site LOD comprises 10% or less of the total upstream contributing drainage area at the point of discharge for sites that discharge directly to a natural stream, waterbody, or tax ditch; or
5.3.3.6 The proposed project will generate only a de minimis discharge and will have no adverse impact on the receiving wetland, watercourse or downstream property as determined on a case-by-case basis
3.3.5 The site LOD comprises 10% or less of the total upstream contributing drainage area at the point of discharge for sites that discharge directly to a natural stream, waterbody, or tax ditch; or
5.3.3.6 The proposed project will generate only a de minimis discharge and will have no adverse impact on the receiving wetland, watercourse or downstream property as determined on a case-by-case basis.
5.3.4 Projects that qualify for and meet standard plan criteria in accordance with subsection 3.7 of these regulations shall be considered in compliance with the Conveyance Event criteria.
5.4 Flooding Event Criteria
5.4.1 The Flooding Event Criteria provide runoff management measures to reduce downstream flooding by optimizing watershed storage and hydrograph timing.
5.4.2 The Flooding Event Volume (Fv) is the volume of runoff produced by the post-development storm having a one percent (1%) probability of occurrence, or the 100-year, 24-hour rainfall event.
5.4.3 Compliance with subsection 5.4 shall be accomplished through the following provisions:
5.4.3.1 The Fv shall be managed using BMPs as set forth in Section 11.0 such that there is no adverse impact by limiting the increase in the downstream post-developed water surface elevation to no more than 0.05 feet; or
5.4.3.2 Improving the existing downstream conveyance system so that the downstream condition meets the "no adverse impact" criteria of subsection 5.4.3.1; or
5.4.3.3 Provisions will be made or exist for a non-erosive conveyance system to tidal waters by either a closed drainage system or by open channel flow that has adequate conveyance for the Fv; or
5.4.3.4 Demonstration that the location of a project within a watershed would aggravate downstream flooding or channel erosion by the imposition of peak control requirements, as evidenced by a downstream analysis that shows the inflection point of the site hydrograph occurs prior to the peak of the upstream hydrograph; or
5.4.3.5 The site LOD comprises 10% or less of the total upstream contributing drainage ar
stration that the location of a project within a watershed would aggravate downstream flooding or channel erosion by the imposition of peak control requirements, as evidenced by a downstream analysis that shows the inflection point of the site hydrograph occurs prior to the peak of the upstream hydrograph; or
5.4.3.5 The site LOD comprises 10% or less of the total upstream contributing drainage area at the point of discharge for sites that discharge directly to a natural stream, waterbody, or tax ditch; or
5.4.3.6 The proposed project will generate only a de minimis discharge and will have no adverse impact on the receiving wetland, watercourse, or downstream property as determined on a case-by-case basis.
5.4.4 Projects that qualify for and meet standard plan criteria in accordance with subsection 3.7 of these regulations shall be considered in compliance with the Flooding Event criteria.
5.5 Alternative Criteria
5.5.1 Land development that discharges to State Waters included in a Designated Watershed, or other watershed management plan approved in accordance with these Regulations, shall meet the alternative criteria identified in the approved watershed plan.
5.5.2 The Department may require alternative stormwater treatment practices or criteria if a receiving waterbody has been identified as impaired, or designated with a specific pollutant reduction target necessary to meet State of Delaware water quality regulations. Such requirements shall be adopted in accordance with Title 29.
5.5.3 The Department may require alternative stormwater treatment practices designed to reduce pollutant loading from a specific source, including but not limited to the discharge from an industrial site regulated under the National Pollutant Discharge Elimination System (NPDES).
5.6 Redevelopment Criteria
5.6.1 The Department recognizes the benefits of redevelopment
d in accordance with Title 29.
5.5.3 The Department may require alternative stormwater treatment practices designed to reduce pollutant loading from a specific source, including but not limited to the discharge from an industrial site regulated under the National Pollutant Discharge Elimination System (NPDES).
5.6 Redevelopment Criteria
5.6.1 The Department recognizes the benefits of redevelopment. The requirements under subsection 5.6 are intended to encourage redevelopment while establishing compliance criteria that meet the overall goals and intent of these regulations.
5.6.2 Compliance with the Resource Protection Event as defined in subsection 5.2.2 shall be accomplished to the maximum extent practicable for redevelopment projects through the following provisions:
5.6.2.1 In the case of redevelopment of a contaminated or Brownfield site, a remediation plan approved by the Department shall meet the stormwater management goals and the intent of these regulations with prior consent and subsequent approval by the Department or Delegated Agency.
5.6.2.2 Redevelopment resulting in less than one acre of disturbed area shall adhere to subsection 3.7 of these Regulations. Projects that cannot adhere to subsection 3.7 shall comply with the applicable subsections of 5.6.2.
5.6.2.3 Redevelopment on sites with stormwater management systems designed and functioning in accordance with the Delaware Sediment and Stormwater Regulations first promulgated on January 23, 1991:
5.6.2.3.1 Redevelopment resulting in a reduction of impervious surface where no known drainage issues exist or will be created and there are no outstanding stormwater-related maintenance issues to be resolved or addressed shall be considered in compliance with these Regulations.
5.6.2.3.2 Redevelopment resulting in an increase in impervious surface where no known drainage issues exist or will be created shall employ treatment or runoff reduction practices to achieve an equivalent open space in good condition for the increased impervious surface
nding stormwater-related maintenance issues to be resolved or addressed shall be considered in compliance with these Regulations.
5.6.2.3.2 Redevelopment resulting in an increase in impervious surface where no known drainage issues exist or will be created shall employ treatment or runoff reduction practices to achieve an equivalent open space in good condition for the increased impervious surface.
5.6.2.4 Redevelopment on sites without stormwater management systems designed and functioning in accordance with the Delaware Sediment and Stormwater Regulations first promulgated on January 23, 1991:
5.6.2.4.1 Redevelopment resulting in a reduction of 15% or greater in impervious surface shall be considered in compliance with these Regulations.
5.6.2.4.2 Redevelopment resulting in a reduction of less than 15% impervious surface where no known drainage issues exist or will be created shall employ treatment or runoff reduction practices to achieve an equivalent 15% reduction in effective imperviousness.
5.6.2.4.3 Redevelopment resulting in an increase in impervious surface shall employ treatment or runoff reduction practices to achieve an equivalent 15% reduction in effective imperviousness for existing impervious areas and an equivalent open space in good condition for an area equivalent to the increase in impervious surface.
5.6.2.5 For those cases in which the minimum runoff reduction requirements are not met an offset in accordance with Section 13.0 shall be provided for any portion of the RPv that does not meet the requirements of subsections 5.6.2.3 and 5.6.2.4 above.
5.6.3 Any redevelopment project, including a contaminated or Brownfield site, that increases the rate or duration of flow to a new or existing point of discharge during the Conveyance Event shall comply with the requirements of subsection 5.3
et in accordance with Section 13.0 shall be provided for any portion of the RPv that does not meet the requirements of subsections 5.6.2.3 and 5.6.2.4 above.
5.6.3 Any redevelopment project, including a contaminated or Brownfield site, that increases the rate or duration of flow to a new or existing point of discharge during the Conveyance Event shall comply with the requirements of subsection 5.3.
5.6.4 Any redevelopment project, including a contaminated or Brownfield site, that increases the rate or duration of flow to a new or existing point of discharge during the Flooding Event shall comply with the requirements of subsection 5.4.
18 DE Reg. 396 (11/01/14)
22 DE Reg. 680 (02/01/19)
6.0 Construction Review of Sediment and Stormwater Management Plan
6.1 Owner Responsibilities
6.1.1 The Owner shall ensure that all elements of the approved Sediment and Stormwater Management Plan are implemented and construction site stormwater management BMPs and post construction stormwater management systems are installed and maintained in accordance with that plan. All construction sites shall comply with these regulations.
6.1.2 The Owner shall comply with the requirements contained in Chapter 60 of Title 7 including the current Delaware Construction General Permit (CGP) .
6.1.3 The Department or Delegated Agency shall have the authority to require revisions to the approved Sediment and Stormwater Management Plan. The Owner is responsible for implementation of plan revisions when deficiencies are noted on the site by the Department or Delegated Agency.
6.1.4 The Owner shall certify to the Department or Delegated Agency that responsible personnel involved in the construction project have successfully completed the Contractor Training Program before initiation of a land disturbing activity. Responsible personnel shall implement the Sediment and Stormwater Management Plan fully through daily oversight of the construction site and guidance of construction personnel while a land disturbing activity is taking place
cy that responsible personnel involved in the construction project have successfully completed the Contractor Training Program before initiation of a land disturbing activity. Responsible personnel shall implement the Sediment and Stormwater Management Plan fully through daily oversight of the construction site and guidance of construction personnel while a land disturbing activity is taking place.
6.1.5 When directed by the Department or Delegated Agency, the Owner shall acquire the services of a third party Certified Construction Reviewer to perform weekly construction reviews of the approved Sediment and Stormwater Management Plan elements as well as construction reviews of installation of stormwater management systems. The Department or Delegated Agency may, at its discretion and following a written request, modify Certified Construction Reviewer reporting frequency for a particular site if site conditions warrant.
6.1.6 Sediment and Stormwater Management Plans approved by the Department shall have a Certified Construction Reviewer.
6.1.7 All costs and fees associated with the use of Certified Construction Reviewers shall be the responsibility of the Owner.
6.1.8 The Owner shall notify the Department or Delegated Agency any time a new Certified Construction Reviewer begins providing construction review for the site.
6.1.9 Upon written notice by the Department, Delegated Agency, or Certified Construction Reviewer, any portion of the work which does not comply with the approved Sediment and Stormwater Management Plan or these regulations shall be corrected by the Owner within the time period specified in the written notice.
6.2 Contractor Training Requirements
6.2.1 A certificate of attendance shall be issued to Responsible Personnel who have attended and successfully completed the Contractor Training Program sponsored or approved by the Department
mply with the approved Sediment and Stormwater Management Plan or these regulations shall be corrected by the Owner within the time period specified in the written notice.
6.2 Contractor Training Requirements
6.2.1 A certificate of attendance shall be issued to Responsible Personnel who have attended and successfully completed the Contractor Training Program sponsored or approved by the Department.
6.2.2 Contractor Training shall be required of a foreperson or superintendent who is in charge of on-site clearing and land disturbing activities for construction projects subject to the requirements of these regulations.
6.2.3 The Contractor Training Program certification shall be valid until the Department notifies the individual or announces in local newspapers that additional training is required due to a change in course content.
6.2.4 The Department shall provide public notification of the date and location of training programs for attendance by responsible personnel and other interested persons.
6.2.5 Enrollment of existing and future responsible personnel is the responsibility of individuals or their employers.
6.2.6 Responsible personnel shall, during active land disturbance, provide daily oversight for site compliance with Chapters 40 and 60 of Title 7 and these regulations.
6.2.7 Responsible personnel shall attend the pre-construction meeting.
6.3 Certified Construction Reviewer Requirements
6.3.1 The Certified Construction Reviewer shall be responsible for reviewing construction activities and reporting on the adequacy of construction in accordance with the approved Sediment and Stormwater Management Plan, in addition to the following items:
6.3.1.1 Provision of a construction review on at least a weekly basis until released from review responsibility by the Department or Delegated Agency.
6.3.1.2 The Department or Delegated Agency may, at its discretion and following a written request, modify Certified Construction Reviewer reporting frequency for a particular site if site conditions warrant
Plan, in addition to the following items:
6.3.1.1 Provision of a construction review on at least a weekly basis until released from review responsibility by the Department or Delegated Agency.
6.3.1.2 The Department or Delegated Agency may, at its discretion and following a written request, modify Certified Construction Reviewer reporting frequency for a particular site if site conditions warrant.
6.3.1.3 Provision of a construction review of stormwater management system construction at a frequency as needed to accurately complete the stormwater BMP construction checklist.
6.3.1.4 Inform the Department or Delegated Agency, the Owner, and the contractor, by a written construction review report of site conditions including any inconsistencies with or inadequacies of the approved plan within five calendar days of the construction review.
6.3.1.5 Referral of the project through the Delegated Agency to the Department for appropriate enforcement action if the Owner fails to address the items contained in the written construction review report. Verbal notice shall be made to the Department within two calendar days and written notice shall be provided to the Department within five calendar days.
6.3.1.6 Prior to the CCR halting reporting activities the CCR must contact the Department or Delegated Agency.
6.3.2 The Certified Construction Reviewer shall function under the direction of a registered professional engineer (P.E.) licensed to practice engineering in the State of Delaware. The following applies to the P.E.'s responsibilities:
6.3.2.1 The P.E. shall be responsible for overseeing and verifying the accuracy of the CCR review.
6.3.2.2 The P.E. shall be responsible for maintaining an ongoing knowledge of the site conditions through periodic site visits or discussions with the CCR.
6.3.2.3 The P.E. shall sign the CCR reports. The P.E. shall only sign CCR reports that were prepared under their direct supervision for sites where the P.E has knowledge of the site conditions
eeing and verifying the accuracy of the CCR review.
6.3.2.2 The P.E. shall be responsible for maintaining an ongoing knowledge of the site conditions through periodic site visits or discussions with the CCR.
6.3.2.3 The P.E. shall sign the CCR reports. The P.E. shall only sign CCR reports that were prepared under their direct supervision for sites where the P.E has knowledge of the site conditions.
6.3.3 Certified Construction Reviewers shall attend and successfully complete the Departmental sponsored or approved Certified Construction Reviewer course. The Certified Construction Reviewer shall be responsible for reviewing construction activities and reporting on the adequacy of construction in accordance with the approved Sediment and Stormwater Management Plan, these regulations, and training received in the Certified Construction Reviewer training course.
6.3.4 Certification as a CCR shall be valid for five years. Recertification may extend certification for an additional five years.
6.3.5 A Certified Construction Reviewer who is not performing the duties prescribed by subsection 6.3 of this regulation may be referred by the local Delegated Agency to the Department for action by providing written notification to the Department and supporting documentation.
6.3.6 In a situation where a Certified Construction Reviewer’s certification is being suspended or revoked, an opportunity for hearing before the Secretary or his designee shall be provided. During a suspension, the Certified Construction Reviewer shall not be allowed to provide construction reviews in accordance with these regulations on any construction sites within the state.
6.4 Department or Delegated Agency Construction Reviews
6.4.1 The Department or Delegated Agency may, at a reasonable time, visit a site subject to these regulations to determine compliance with these regulations, including implementation of the Sediment and Stormwater Management Plan
d to provide construction reviews in accordance with these regulations on any construction sites within the state.
6.4 Department or Delegated Agency Construction Reviews
6.4.1 The Department or Delegated Agency may, at a reasonable time, visit a site subject to these regulations to determine compliance with these regulations, including implementation of the Sediment and Stormwater Management Plan.
6.4.2 The Department or Delegated Agency shall conduct regular reviews of the construction site at a frequency to ensure that all elements of the approved Sediment and Stormwater Management Plan are implemented and all construction site stormwater management BMPs and post construction stormwater management systems are installed and maintained in accordance with that plan.
6.4.3 All Department or Delegated Agency construction reviews shall be documented in writing with a copy provided to the Owner. The review report shall document site conditions relevant to the Sediment and Stormwater Management Plan, identify deficiencies that warrant correction, and provide a time period for the Owner to complete corrective action.
6.4.4 When the Department or Delegated Agency determines a deficiency in the approved Sediment and Stormwater Management Plan, a revision to the approved plans may be required. A change to the approved Sediment and Stormwater Management Plan shall be approved by the Department or Delegated Agency before construction.
6.5 Required Construction Reviews and Notification Steps
6.5.1 The Owner shall notify the Department or Delegated Agency in writing at least five calendar days before the initiation of construction. The notification shall include the contact information for the responsible person. The notification shall verify that the Sediment and Stormwater Management Plan for the project has been approved and that permit coverage for Storm Water Discharges Associated with Construction Activity has been gained through submittal of a Notice of Intent to the Department
s before the initiation of construction. The notification shall include the contact information for the responsible person. The notification shall verify that the Sediment and Stormwater Management Plan for the project has been approved and that permit coverage for Storm Water Discharges Associated with Construction Activity has been gained through submittal of a Notice of Intent to the Department. If there is a Certified Construction Reviewer requirement for the site, the application for Certified Construction Reviewer shall be included with the notification.
6.5.2 A pre-construction meeting shall be required. The pre-construction meeting shall be held on site, unless another location is approved by the Department or Delegated Agency on a case-by-case basis. The required attendees for a pre-construction meeting are the owner or owner's representative, the site project manager, site contractor, Certified Construction Reviewer (if required), the Responsible Person, and the Department or Delegated Agency representative.
6.5.3 The Department or Delegated Agency shall determine when Standard Plan applications require a pre-construction meeting and construction reviews based on the project type and land disturbance on a case-by-case basis.
6.5.4 Upon completion of installation of perimeter controls, the Department or Delegated Agency shall conduct a perimeter control review before commencement of bulk grading or other construction activities on the site.
6.5.5 All stormwater management systems shall be reviewed during construction with enough frequency to document that the system has been constructed in accordance with the approved Sediment and Stormwater Management Plan, the design specifications, and the appropriate stormwater management system construction checklist. The Owner shall provide adequate notice to the Department or Delegated Agency and Certified Construction Reviewer, if applicable, before initiating construction of stormwater management systems
t the system has been constructed in accordance with the approved Sediment and Stormwater Management Plan, the design specifications, and the appropriate stormwater management system construction checklist. The Owner shall provide adequate notice to the Department or Delegated Agency and Certified Construction Reviewer, if applicable, before initiating construction of stormwater management systems. The Department, Delegated Agency, or Certified Construction Reviewer shall be responsible for conducting and documenting these reviews, as required. Photographic documentation of construction of the stormwater management system is required.
6.5.6 Upon project completion a final construction review shall be conducted and a final review report shall be completed by the Department or Delegated Agency to ensure compliance with the approved Sediment and Stormwater Management Plan. The Department or Delegated Agency shall issue a Notice of Completion for a project when all of the following criteria have been met:
6.5.6.1 All items and conditions of the approved Sediment and Stormwater Management Plan have been satisfied.
6.5.6.2 Post construction verification documents demonstrate that the stormwater management systems have been constructed in accordance with the approved Sediment and Stormwater Management Plan and accepted by the approving agency.
6.5.6.3 Operation and Maintenance Plan has been approved by the Department or Delegated Agency.
6.5.6.4 Final stabilization of disturbed areas on the site has been achieved.
6.5.6.5 A copy of the approved Record Plan showing easements or maintenance notes associated with the approved Sediment and Stormwater Management Plan has been submitted to the Department or Delegated Agency.
18 DE Reg. 396 (11/01/14)
22 DE Reg. 680 (02/01/19)
7.0 Post Construction Maintenance of Stormwater Management Systems
7.1 Stormwater management systems constructed to comply with 7 Del.C. Ch. 40 and these regulations shall be maintained in accordance with the provisions of this section
h the approved Sediment and Stormwater Management Plan has been submitted to the Department or Delegated Agency.
18 DE Reg. 396 (11/01/14)
22 DE Reg. 680 (02/01/19)
7.0 Post Construction Maintenance of Stormwater Management Systems
7.1 Stormwater management systems constructed to comply with 7 Del.C. Ch. 40 and these regulations shall be maintained in accordance with the provisions of this section.
7.1.1 Maintenance responsibility lies with the Owner until the time that a legal transfer of ownership has been executed. Prior notice of the transfer shall be provided to the Department or Delegated Agency 30 business days before the transfer occurs.
7.1.2 The stormwater management system shall run with the land and be binding upon the landowner and any successors in interest. Maintenance of these systems shall ensure that the stormwater management system is performing in accordance with the approved engineered design, within the tolerances of the accepted post construction verification documents, and in compliance with these regulations.
7.1.3 The Owner of a stormwater management system established in accordance with these regulations may offer for dedication to a delegated agency, public entity, municipality, stormwater utility, or private entity, a stormwater management system, together with the easements and appurtenances as may be reasonably necessary for the proper functioning of the system.
7.1.4 All stormwater management systems must be designed so as to be accessible for maintenance. If required, a maintenance right-of-way or easement must extend to the stormwater management system from a public or private road. The easement or right of way shall specify the ownership and party responsible for maintenance.
7.2 Owner Responsibilities
7.2.1 The Owner shall ensure that the stormwater management system is functioning in accordance with the approved engineering design, within the tolerances of the accepted post construction verification documents, and in compliance with these regulations
ublic or private road. The easement or right of way shall specify the ownership and party responsible for maintenance.
7.2 Owner Responsibilities
7.2.1 The Owner shall ensure that the stormwater management system is functioning in accordance with the approved engineering design, within the tolerances of the accepted post construction verification documents, and in compliance with these regulations. The Owner will promptly repair and restore stormwater management systems.
7.2.1.1 Such repairs, restoration, or maintenance shall be conducted in accordance with the approved Sediment and Stormwater Management Plan, the Operation and Maintenance Plan, Standard Guidelines for Operation and Maintenance of Stormwater Management Systems, and directions provided by the Department or Delegated Agency.
7.2.1.2 When the Department or Delegated Agency gives direction for maintenance, those maintenance activities shall be conducted by the Owner within the time period established by the Department or Delegated Agency.
7.2.2 Any change made to the stormwater management system shall require the Owner to obtain approval of the Department or Delegated Agency, including updating of the Operation and Maintenance Plan and Planting Plan details as necessary.
7.2.3 The Owner shall submit a scope of work for non-routine maintenance to the Department or Delegated Agency for approval prior to implementation.
7.2.4 Maintenance responsibilities may be shared through a legal agreement between the Owner and another entity such as a delegated agency, public utility, municipality, stormwater utility, maintenance company, or other private entity. Responsibility for maintenance shall be joint and several among the parties to the agreement to share those responsibilities
y for approval prior to implementation.
7.2.4 Maintenance responsibilities may be shared through a legal agreement between the Owner and another entity such as a delegated agency, public utility, municipality, stormwater utility, maintenance company, or other private entity. Responsibility for maintenance shall be joint and several among the parties to the agreement to share those responsibilities.
7.2.5 If the Sediment and Stormwater Management Plan includes structural or nonstructural stormwater management measures located within a tax ditch right-of-way the Owner shall enter into an agreement with the tax ditch organization for maintenance of those stormwater management measures.
7.2.6 The Owner shall provide the Department or Delegated Agency with the contact information for the current person responsible for receiving the Department or Delegated Agency maintenance review reports.
7.3 Maintenance Reviews
7.3.1 The Department, Delegated Agency, or duly authorized agent shall conduct maintenance reviews of completed stormwater management systems. The Department, Delegated Agency, or duly authorized agent shall have the right of entry and access at reasonable times to perform stormwater management system maintenance reviews.
7.3.2 The maintenance review performed by the Department, Delegated Agency, or duly authorized agent shall document maintenance and repair needs

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## Nearby sections

- [7 Del. Admin. Code § 5101 7 DE Admin. Code 5101. Sediment and Stormwater Regulations](https://www.frixlaw.com/law-library/statutes/STATE_DE_ADC_T7_5101.md)
- [7 Del. Admin. Code § 5102 7 DE Admin. Code 5102. Regulation Governing Beach Protection and the Use of Beaches](https://www.frixlaw.com/law-library/statutes/STATE_DE_ADC_T7_5102.md)
- [7 Del. Admin. Code § 5103 7 DE Admin. Code 5103. Delaware Dam Safety Regulations](https://www.frixlaw.com/law-library/statutes/STATE_DE_ADC_T7_5103.md)

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Source: Frix Law Library, https://www.frixlaw.com/law-library/statutes/STATE_DE_ADC_T7_5101. Check the current official text before relying on it. Not legal advice.