Virginia Law

Part V. Criteria and Requirements for Regulated Land-Disturbing Activities

Article 1
Administrative Criteria

9VAC25-875-470. Applicability.

A. Land-disturbing activities that meet one of the criteria in this subsection are regulated as follows:

1. Land-disturbing activity that disturbs 10,000 square feet or more, although a locality may reduce this regulatory threshold to a smaller area of disturbed land, is less than one acre, not in an area of a locality designated as a Chesapeake Bay Preservation Area, and not part of a common plan of development or sale, is subject to criteria defined in Article 2 (9VAC25-875-540 et seq.) of this part of this chapter.

2. Land-disturbing activity that disturbs 2,500 square feet or more, although a locality may reduce this regulatory threshold to a smaller area of disturbed land, is less than one acre, and in an area of a locality designated as a Chesapeake Bay Preservation Area is subject to criteria defined in Article 2 and Article 3 (9VAC25-875-570 et seq.) of this part unless Article 4 (9VAC25-875-670 et seq.) of this part is applicable, as determined in accordance with 9VAC25-875-480 and 9VAC25-875-490. For land-disturbing activities for single-family detached residential structures, Article 2 of this part and water quantity technical criteria, 9VAC25-875-600, shall apply to any land-disturbing activity that disturbs 2,500 square feet or more of land, and the locality also may require compliance with the water quality technical criteria, 9VAC25-875-580 and 9VAC25-875-590.

3. Land-disturbing activity that disturbs less than one acre, but is part of a larger common plan of development or sale that disturbs one acre or more, is subject to criteria defined in Article 2 and Article 3 of this part unless Article 4 of this part is applicable, as determined in accordance with 9VAC25-875-480 and 9VAC25-875-490.

4. Land-disturbing activity that disturbs one acre or more is subject to criteria defined in Article 2 and Article 3 of this part unless Article 4 of this part is applicable, as determined in accordance with 9VAC25-875-480 and 9VAC25-875-490.

B. A locality may, by local ordinance adopted pursuant to § 62.1-44.15:33 or 62.1-44.15:65 of the Code of Virginia, adopt more stringent local requirements.

Statutory Authority

§ 62.1-44.15:28 of the Code of Virginia.

Historical Notes

Derived from Virginia Register Volume 40, Issue 8, eff. July 1, 2024.

9VAC25-875-480. Applicability of other laws and regulations; time limits on applicability of approved design criteria.

A. Nothing in this chapter shall be construed as limiting the applicability of other laws and regulations, including, the Clean Water Act, VESMA, ESCL, and the Chesapeake Bay Preservation Act, and all applicable regulations adopted in accordance with those laws, or the rights of other federal agencies, state agencies, or local governments to impose more stringent technical criteria or other requirements as allowed by law.

B. Land-disturbing activities that obtain an initial permit or commence land disturbance prior to July 1, 2014, shall be conducted in accordance with the technical criteria of Article 4 (9VAC25-875-670 et seq.) of this part. Such projects shall remain subject to the technical criteria of Article 4 of this part for two additional permit cycles. After such time, portions of the project not under construction shall become subject to any new technical criteria adopted by the board.

C. Land-disturbing activities that obtain an initial permit on or after July 1, 2014, shall be conducted in accordance with the technical criteria of Article 3 (9VAC25-875-570 et seq.) of this part, except as provided for in 9VAC25-875-490. Land-disturbing activities conducted in accordance with the technical criteria of Article 3 of this part shall remain subject to the technical criteria of Article 3 of this part for two additional permit cycles. After such time, portions of the project not under construction shall become subject to any new technical criteria adopted by the board.

D. Nothing in this section shall preclude an operator from constructing to a more stringent standard at the operator's discretion.

Statutory Authority

§ 62.1-44.15:28 of the Code of Virginia.

Historical Notes

Derived from Virginia Register Volume 40, Issue 8, eff. July 1, 2024.

9VAC25-875-490. Grandfathering.

A. Any land-disturbing activity shall be considered grandfathered by the VESMP authority and shall be subject to the technical criteria of Article 4 (9VAC25-875-670 et seq.) of this part provided:

1. A proffered or conditional zoning plan, zoning with a plan of development, preliminary or final subdivision plat, preliminary or final site plan, or any document determined by the locality to be equivalent thereto (i) was approved by the locality prior to July 1, 2012; (ii) provided a layout as defined in 9VAC25-875-670; (iii) will comply with the technical criteria of Article 4 of this part; and (iv) has not been subsequently modified or amended in a manner resulting in an increase in the amount of phosphorus leaving each point of discharge and such that there is no increase in the volume or rate of runoff;

2. A permit has not been issued prior to July 1, 2014; and

3. Land disturbance did not commence prior to July 1, 2014.

B. Locality, state, and federal projects shall be considered grandfathered by the VESMP authority and shall be subject to the technical criteria of Article 4 of this part provided:

1. There has been an obligation of locality, state, or federal funding, in whole or in part, prior to July 1, 2012, or the department has approved a stormwater management plan prior to July 1, 2012;

2. A permit has not been issued prior to July 1, 2014; and

3. Land disturbance did not commence prior to July 1, 2014.

C. Land disturbing activities grandfathered under subsections A and B of this section shall remain subject to the technical criteria of Article 4 of this part for one additional permit cycle. After such time, portions of the project not under construction shall become subject to any new technical criteria adopted by the board.

D. In cases where governmental bonding or public debt financing has been issued for a project prior to July 1, 2012, such project shall be subject to the technical criteria of Article 4 of this part.

E. Nothing in this section shall preclude an operator from constructing to a more stringent standard at the operator's discretion.

Statutory Authority

§ 62.1-44.15:28 of the Code of Virginia.

Historical Notes

Derived from Virginia Register Volume 40, Issue 8, eff. July 1, 2024.

9VAC25-875-500. Stormwater pollution prevention plan requirements.

A. A stormwater pollution prevention plan shall include an approved erosion and sediment control plan, an approved stormwater management plan, a pollution prevention plan for regulated land-disturbing activities, and a description of any additional control measures necessary to address a TMDL pursuant to subsection E of this section.

B. An erosion and sediment control plan consistent with the requirements of 9VAC25-875-550 must be designed and implemented during construction activities. Prior to land disturbance, this plan must be approved by the VESCP authority, VESMP authority, or the department.

C. A stormwater management plan consistent with the requirements of 9VAC25-875-510 must be designed and implemented during construction activities. Prior to land disturbance, this plan must be approved by the VESMP authority or the department.

D. A pollution prevention plan that identifies potential sources of pollutants that may reasonably be expected to affect the quality of stormwater discharges from the construction site and describe control measures that will be used to minimize pollutants in stormwater discharges from the construction site must be developed before land disturbance commences.

E. In addition to the requirements of subsections A through D of this section, if a specific wasteload allocation for a pollutant has been established in an approved TMDL and is assigned to stormwater discharges from a construction activity, additional control measures must be identified and implemented by the operator so that discharges are consistent with the assumptions and requirements of the wasteload allocation.

F. The stormwater pollution prevention plan (SWPPP) must address the following requirements as specified in 40 CFR 450.21, to the extent otherwise required by state law or regulations and any applicable requirements of a permit:

1. Control stormwater volume and velocity within the site to minimize soil erosion;

2. Control stormwater discharges, including both peak flow rates and total stormwater volume, to minimize erosion at outlets and to minimize downstream channel and stream bank erosion;

3. Minimize the amount of soil exposed during construction activity;

4. Minimize the disturbance of steep slopes;

5. Minimize sediment discharges from the site. The design, installation, and maintenance of erosion and sediment controls must address factors such as the amount, frequency, intensity, and duration of precipitation, the nature of resulting stormwater runoff, and soil characteristics, including the range of soil particle sizes expected to be present on the site;

6. Provide and maintain natural buffers around surface waters, direct stormwater to vegetated areas to increase sediment removal, and maximize stormwater infiltration, unless infeasible;

7. Minimize soil compaction and, unless infeasible, preserve topsoil;

8. Stabilization of disturbed areas must, at a minimum, be initiated immediately whenever any clearing, grading, excavating, or other earth disturbing activities have permanently ceased on any portion of the site, or temporarily ceased on any portion of the site and will not resume for a period exceeding 14 calendar days. Stabilization must be completed within a period of time determined by the VESMP authority or the department as the VSMP authority. In arid, semi-arid, and drought-stricken areas where initiating vegetative stabilization measures immediately is infeasible, alternative stabilization measures must be employed as specified by the VESMP authority or department; and

9. Utilize outlet structures that withdraw water from the surface, unless infeasible, when discharging from basins and impoundments.

G. The SWPPP shall be amended whenever there is a change in design, construction, operation, or maintenance that has a significant effect on the discharge of pollutants to state waters and that has not been previously addressed in the SWPPP. The SWPPP must be maintained at a central location onsite. If an onsite location is unavailable, notice of the SWPPP's location must be posted near the main entrance at the construction site.

Statutory Authority

§ 62.1-44.15:28 of the Code of Virginia.

Historical Notes

Derived from Virginia Register Volume 40, Issue 8, eff. July 1, 2024.

9VAC25-875-510. Stormwater management plan requirements.

A. A stormwater management plan shall be developed and submitted to the VESMP authority or the department as the VSMP authority. The stormwater management plan shall be implemented as approved or modified by the VESMP authority or department and shall be developed in accordance with the following:

1. A stormwater management plan for a land-disturbing activity shall apply the stormwater management technical criteria set forth in this part to the entire land-disturbing activity. Individual lots in new residential, commercial, or industrial developments, including those developed under subsequent owners, shall not be considered separate land-disturbing activities.

2. A stormwater management plan shall consider all sources of surface runoff and all sources of subsurface and groundwater flows converted to surface runoff.

B. A complete stormwater management plan shall include the following elements:

1. Information on the type of and location of stormwater discharges, information on the features to which stormwater is being discharged including surface waters or karst features if present, and predevelopment and post-development drainage areas;

2. Contact information including the name, address, telephone number, and email address of the owner and the tax reference number and parcel number of the property or properties affected;

3. A narrative that includes a description of current site conditions and final site conditions or if allowed by the VESMP authority or department, the information provided and documented during the review process that addresses the current and final site conditions;

4. A general description of the proposed stormwater management facilities and the mechanism through which the facilities will be operated and maintained after construction is complete;

5. Information on the proposed stormwater management facilities, including (i) detailed narrative on the conversion to a long-term stormwater management facility if the facility was used as a temporary ESC measure; (ii) the type of facilities; (iii) location, including geographic coordinates; (iv) acres treated; and (v) the surface waters or karst features into which the facility will discharge;

6. Hydrologic and hydraulic computations, including runoff characteristics;

7. Documentation and calculations verifying compliance with the water quality and quantity requirements of this chapter;

8. A map of the site that depicts the topography of the site and includes:

a. All contributing drainage areas;

b. Existing streams, ponds, culverts, ditches, wetlands, other water bodies, and floodplains;

c. Soil types, geologic formations if karst features are present in the area, forest cover, and other vegetative areas;

d. Current land use including existing structures, roads, and locations of known utilities and easements;

e. Sufficient information on adjoining parcels to assess the impacts of stormwater from the site on these parcels;

f. The limits of clearing and grading, and the proposed drainage patterns on the site;

g. Proposed buildings, roads, parking areas, utilities, and stormwater management facilities; and

h. Proposed land use with tabulation of the percentage of surface area to be adapted to various uses, including planned locations of utilities, roads, and easements;

9. If an operator intends to meet the requirements established in 9VAC25-875-580 or 9VAC25-875-600 through the use of offsite compliance options, where applicable, then a letter of availability from the offsite provider must be included; and

10. If payment of a fee is required with the stormwater management plan submission to the VESMP authority or the department, the fee in accordance with Part VIII (9VAC25-875-1290 et seq.) of this chapter must have been submitted.

C. All final plan elements, specifications, or calculations of the stormwater management plans whose preparation requires a license under Chapter 4 (§ 54.1-400 et seq.) or 22 (§ 54.1- 2200 et seq.) of Title 54.1 of the Code of Virginia shall be appropriately signed and sealed by a professional who is licensed to engage in practice in the Commonwealth of Virginia. Nothing in this subsection shall authorize any person to engage in practice outside that person's area of professional competence.

Statutory Authority

§ 62.1-44.15:28 of the Code of Virginia.

Historical Notes

Derived from Virginia Register Volume 40, Issue 8, eff. July 1, 2024.

9VAC25-875-520. Pollution prevention plans.

A. A plan for implementing pollution prevention measures during construction activities shall be developed, implemented, and updated as necessary. The pollution prevention plan shall detail the design, installation, implementation, and maintenance of effective pollution prevention measures as specified in 40 CFR 450.21(d) to minimize the discharge of pollutants. At a minimum, such measures must be designed, installed, implemented, and maintained to:

1. Minimize the discharge of pollutants from equipment and vehicle washing, wheel wash water, and other wash waters. Wash waters must be treated in a sediment basin or alternative control that provides equivalent or better treatment prior to discharge;

2. Minimize the exposure of building materials, building products, construction wastes, trash, landscape materials, fertilizers, pesticides, herbicides, detergents, sanitary waste, and other materials present on the site to precipitation and to stormwater; and

3. Minimize the discharge of pollutants from spills and leaks and implement chemical spill and leak prevention and response procedures.

B. The pollution prevention plan shall include effective best management practices to prohibit the following discharges in accordance with 40 CFR 450.21(e):

1. Wastewater from washout of concrete, unless managed by an appropriate control;

2. Wastewater from washout and cleanout of stucco, paint, form release oils, curing compounds, and other construction materials;

3. Fuels, oils, or other pollutants used in vehicle and equipment operation and maintenance; and

4. Soaps or solvents used in vehicle and equipment washing.

C. Discharges from dewatering activities, including discharges from dewatering of trenches and excavations, are prohibited unless managed by appropriate controls in accordance with 40 CFR 450.21(c).

Statutory Authority

§ 62.1-44.15:28 of the Code of Virginia.

Historical Notes

Derived from Virginia Register Volume 40, Issue 8, eff. July 1, 2024.

9VAC25-875-530. Applying for permit coverage.

A. The operator must submit a complete and accurate registration statement in accordance with the General VPDES Permit for Discharges of Stormwater from Construction Activities (9VAC25-880) if such statement is required, on the official department form to the VESMP or department as the VSMP authority in order to apply for permit coverage. The registration statement must be signed by the operator in accordance with 9VAC25-875-940. In accordance with § 62.1-44.15:28 of the Code of Virginia, no registration statement is required for coverage under the General VPDES Permit for Discharges of Stormwater from Construction Activities (Construction General Permit) for a small construction activity involving a single-family detached residential structure, within or outside a common plan of development or sale.

B. A person shall not conduct any land-disturbing activity until (i) the person has submitted to the appropriate VESMP authority or the department as the VSMP authority an application that includes a permit registration statement, if required, an ESM plan or an executed agreement in lieu of a plan, if required, and (ii) the VESMP authority or department has issued its land-disturbance approval. For a single family detached residential structure with less than one acre of land disturbance, an agreement in lieu of a plan may be used when either (a) it is located within a common plan of development or sale with an approved stormwater pollution prevention plan consistent with 9VAC25-875-500 and a permit, if required; or (b) the single-family detached residential is located outside of a common plan of development or sale.

C. In addition, as a prerequisite to engaging in an approved land-disturbing activity, the name of the individual who will be assisting the owner in carrying out the activity and holds a Responsible Land Disturber Certificate pursuant to § 62.1-44.15:30 of the Code of Virginia shall be submitted to the VESMP authority or department.

D. Any VESMP authority or the department as the VSMP authority may waive the Responsible Land Disturber Certificate requirement for an agreement in lieu of a plan; however, if a violation occurs during the land-disturbing activity, then the owner shall correct the violation and provide the name of the individual holding a Responsible Land Disturber Certificate as provided by § 62.1-14:30 of the Code of Virginia. Failure to provide the name of an individual holding a Responsible Land Disturber Certificate prior to engaging in land-disturbing activities may result in revocation of the land-disturbance approval and shall subject the owner to the penalties provided in the VESMA.

Statutory Authority

§ 62.1-44.15:28 of the Code of Virginia.

Historical Notes

Derived from Virginia Register Volume 40, Issue 8, eff. July 1, 2024.

9VAC25-875-535. Long-term maintenance of stormwater management facilities.

A. The operator shall submit a construction record drawing for permanent stormwater management facilities to the VESMP or VSMP authority based on the locality where the land-disturbing activity will occur. The record drawing shall contain a statement signed by a professional registered in the Commonwealth of Virginia pursuant to Chapter 4 (§ 54.1-400 et seq.) of Title 54.1 of the Code of Virginia, stating that to the best of the professional's knowledge, the construction record drawing shows all adjustments and revisions to the stormwater management plan made during construction and serve as a permanent record of the actual location of all constructed elements.

B. The provision of long-term responsibility for and maintenance of stormwater management facilities and other techniques specified to manage the quality or quantity of runoff is required. Such requirements shall be set forth in an instrument recorded in the local land records prior to permit termination or earlier as required by the authority and shall at a minimum:

1. Be submitted to the authority for review and approval prior to the approval of the stormwater management plan;

2. Be stated to run with the land;

3. Provide for all necessary access to the property for purposes of maintenance and regulatory inspections;

4. Provide for inspections and maintenance and the submission of inspection and maintenance reports to the VESCP, VSMP, or VESMP authority; and

5. Be enforceable by all appropriate governmental parties.

C. At the discretion of the VESMP authority, such recorded instruments need not be required for stormwater management facilities designed to treat stormwater runoff primarily from an individual residential lot on which they are located, provided it is demonstrated to the satisfaction of the authority that future maintenance of such facilities will be addressed through an enforceable mechanism at the discretion of the authority.

Statutory Authority

§ 62.1-44.15:28 of the Code of Virginia.

Historical Notes

Derived from Virginia Register Volume 40, Issue 8, eff. July 1, 2024.

Article 2
Soil Erosion Requirements

9VAC25-875-540. Applicability.

A. This article sets forth minimum standards for the effective control of soil erosion, sediment deposition, and nonagricultural runoff.

B. In accordance with Item 360 I1 of Chapter 3 of the 2012 Acts of Assembly, Special Session I, public institutions of higher education, including community colleges, colleges, and universities, shall be subject to project review and compliance for state erosion and sediment control requirements by the VESCP or VESMP authority of the locality within which the land-disturbing activity is located, unless such institution submits standards and specifications to the department in accordance with § 62.1-44.15:31 of the Code of Virginia.

Statutory Authority

§ 62.1-44.15:28 of the Code of Virginia.

Historical Notes

Derived from Virginia Register Volume 40, Issue 8, eff. July 1, 2024.

9VAC25-875-550. Erosion and sediment control plan requirements.

A. An erosion and sediment control plan shall be filed for a development and the buildings constructed within, regardless of the phasing of construction. The erosion and sediment control plan shall contain all major conservation decisions to ensure that the entire unit of land will be so treated to achieve the conservation objectives in 9VAC25-875-560. The erosion and sediment control plan may include:

1. Appropriate maps;

2. An appropriate soil and water plan inventory and management information with needed interpretations; and

3. A record of decisions contributing to conservation treatment.

B. The person responsible for carrying out the plan shall provide the name of an individual holding a certificate who will be in charge of and responsible for carrying out the land-disturbing activity to the VESCP or VESMP authority. However, the VESCP or VESMP authority may waive the Responsible Land Disturber Certificate requirement for an agreement in lieu of a plan in accordance with § 62.1-44.15:34 or 62.1-44.15:55 of the Code of Virginia.

C. If individual lots or sections in a residential development are being developed by different property owners, all land-disturbing activities related to the building construction shall be covered by an erosion and sediment control plan or an agreement in lieu of a plan signed by the property owner.

D. Land-disturbing activity of less than 10,000 square feet on individual lots in a residential development shall not be considered exempt from the provisions of the VESMA, ESCL, or this chapter if the total land-disturbing activity in the development is equal to or greater than 10,000 square feet.

Statutory Authority

§ 62.1-44.15:28 of the Code of Virginia.

Historical Notes

Derived from Virginia Register Volume 40, Issue 8, eff. July 1, 2024.

9VAC25-875-560. Erosion and sediment control criteria, techniques, and methods: minimum standards.

An erosion and sediment control plan consistent with the following criteria, techniques, and methods shall be submitted to the VESMP authority or VESCP authority for review and approval:

1. Permanent or temporary soil stabilization shall be applied to denuded areas within seven days after final grade is reached on any portion of the site. Temporary soil stabilization shall be applied within seven days to denuded areas that may not be at final grade but will remain dormant for longer than 14 days. Permanent stabilization shall be applied to areas that are to be left dormant for more than one year.

2. During construction of the project, soil stockpiles and borrow areas shall be stabilized or protected with sediment trapping measures. The applicant is responsible for the temporary protection and permanent stabilization of all soil stockpiles on site as well as borrow areas and soil intentionally transported from the project site.

3. A permanent vegetative cover shall be established on denuded areas not otherwise permanently stabilized. Permanent vegetation shall not be considered established until a ground cover is achieved that is uniform, is mature enough to survive, and will inhibit erosion.

4. Sediment basins and traps, perimeter dikes, sediment barriers, and other measures intended to trap sediment shall be constructed as a first step in any land-disturbing activity and shall be made functional before upslope land disturbance takes place.

5. Stabilization measures shall be applied to earthen structures such as dams, dikes, and diversions immediately after installation.

6. Sediment traps and sediment basins shall be designed and constructed based upon the total drainage area to be served by the trap or basin.

a. The minimum storage capacity of a sediment trap shall be 134 cubic yards per acre of drainage area and the trap shall only control drainage areas less than three acres.

b. Surface runoff from disturbed areas that is comprised of flow from drainage areas greater than or equal to three acres shall be controlled by a sediment basin. The minimum storage capacity of a sediment basin shall be 134 cubic yards per acre of drainage area. The outfall system shall, at a minimum, maintain the structural integrity of the basin during a 25-year storm of 24-hour duration. Runoff coefficients used in runoff calculations shall correspond to a bare earth condition or those conditions expected to exist while the sediment basin is utilized.

7. Cut and fill slopes shall be designed and constructed in a manner that will minimize erosion. Slopes that are found to be eroding excessively within one year of permanent stabilization shall be provided with additional slope stabilizing measures until the problem is corrected.

8. Concentrated runoff shall not flow down cut or fill slopes unless contained within an adequate temporary or permanent channel, flume, or slope drain structure.

9. Whenever water seeps from a slope face, adequate drainage or other protection shall be provided.

10. All storm sewer inlets that are made operable during construction shall be protected so that sediment-laden water cannot enter the conveyance system without first being filtered or otherwise treated to remove sediment.

11. Before newly constructed stormwater conveyance channels or pipes are made operational, adequate outlet protection and any required temporary or permanent channel lining shall be installed in both the conveyance channel and receiving channel.

12. When work in a live watercourse is performed, precautions shall be taken to minimize encroachment, control sediment transport, and stabilize the work area to the greatest extent possible during construction. Nonerodible material shall be used for the construction of causeways and cofferdams. Earthen fill may be used for these structures if armored by nonerodible cover materials.

13. When a live watercourse must be crossed by construction vehicles more than twice in any six-month period, a temporary vehicular stream crossing constructed of nonerodible material shall be provided.

14. All applicable federal, state, and local requirements pertaining to working in or crossing live watercourses shall be met.

15. The bed and banks of a watercourse shall be stabilized immediately after work in the watercourse is completed.

16. Underground utility lines shall be installed in accordance with the following standards in addition to other applicable criteria:

a. No more than 500 linear feet of trench may be opened at one time.

b. Excavated material shall be placed on the uphill side of trenches.

c. Effluent from dewatering operations shall be filtered or passed through an approved sediment trapping device, or both and discharged in a manner that does not adversely affect flowing streams or off-site property.

d. Material used for backfilling trenches shall be properly compacted in order to minimize erosion and promote stabilization.

e. Restabilization shall be accomplished in accordance with this chapter.

f. Applicable safety requirements shall be complied with.

17. Where construction vehicle access routes intersect paved or public roads, provisions shall be made to minimize the transport of sediment by vehicular tracking onto the paved surface. Where sediment is transported onto a paved or public road surface, the road surface shall be cleaned thoroughly at the end of each day. Sediment shall be removed from the roads by shoveling or sweeping and transported to a sediment control disposal area. Street washing shall be allowed only after sediment is removed in this manner. This provision shall apply to individual development lots as well as to larger land-disturbing activities.

18. All temporary erosion and sediment control measures shall be removed within 30 days after final site stabilization or after the temporary measures are no longer needed, unless otherwise authorized by the VESCP or VESMP authority. Trapped sediment and the disturbed soil areas resulting from the disposition of temporary measures shall be permanently stabilized to prevent further erosion and sedimentation.

19. Properties and waterways downstream from development sites shall be protected from sediment deposition, erosion, and damage due to increases in volume, velocity, and peak flow rate of stormwater runoff for the stated frequency storm of 24-hour duration in accordance with the following standards and criteria. Stream restoration and relocation projects that incorporate natural channel design concepts are not manmade channels and shall be exempt from any flow rate capacity and velocity requirements for natural or manmade channels:

a. Concentrated stormwater runoff leaving a development site shall be discharged directly into an adequate natural or manmade receiving channel, pipe, or storm sewer system. For those sites where runoff is discharged into a pipe or pipe system, downstream stability analyses at the outfall of the pipe or pipe system shall be performed.

b. Adequacy of all channels and pipes shall be verified in the following manner:

(1) The applicant shall demonstrate that the total drainage area to the point of analysis within the channel is 100 times greater than the contributing drainage area of the project in question; or

(2) (a) Natural channels shall be analyzed by the use of a two-year storm to verify that stormwater will not overtop channel banks nor cause erosion of channel bed or banks.

(b) All previously constructed manmade channels shall be analyzed by the use of a 10-year storm to verify that stormwater will not overtop the stormwater's banks and by the use of a two-year storm to demonstrate that stormwater will not cause erosion of channel bed or banks; and

(c) Pipes and storm sewer systems shall be analyzed by the use of a 10-year storm to verify that stormwater will be contained within the pipe or system.

c. If existing natural receiving channels or previously constructed manmade channels or pipes are not adequate, the applicant shall:

(1) Improve the channels to a condition where a 10-year storm will not overtop the banks and a two-year storm will not cause erosion to the channel, the bed, or the banks;

(2) Improve the pipe or pipe system to a condition where the 10-year storm is contained within the appurtenances;

(3) Develop a site design that will not cause the predevelopment peak runoff rate from a two-year storm to increase when runoff outfalls into a natural channel or will not cause the predevelopment peak runoff rate from a 10-year storm to increase when runoff outfalls into a manmade channel; or

(4) Provide a combination of channel improvement, stormwater detention, or other measures that is satisfactory to the VESCP or VESMP authority to prevent downstream erosion.

d. The applicant shall provide evidence of permission to make the improvements.

e. All hydrologic analyses shall be based on the existing watershed characteristics and the ultimate development condition of the subject project.

f. If the applicant chooses an option that includes stormwater detention, the applicant shall obtain approval from the VESCP or VESMP authority for a plan for maintenance of the detention facilities. The plan shall set forth the maintenance requirements of the facility and the person responsible for performing the maintenance.

g. Outfall from a detention facility shall be discharged to a receiving channel, and energy dissipators shall be placed at the outfall of all detention facilities as necessary to provide a stabilized transition from the facility to the receiving channel.

h. All on-site channels must be verified to be adequate.

i. Increased volumes of sheet flows that may cause erosion or sedimentation on adjacent property shall be diverted to a stable outlet, adequate channel, pipe, or pipe system or to a detention facility.

j. In applying these stormwater management criteria, individual lots or parcels in a residential, commercial, or industrial development shall not be considered to be separate development projects. Instead, the development, as a whole, shall be considered to be a single development project. Hydrologic parameters that reflect the ultimate development condition shall be used in all engineering calculations.

k. All measures used to protect properties and waterways shall be employed in a manner that minimizes impacts on the physical, chemical, and biological integrity of rivers, streams, and other waters of the state.

l. Any plan approved prior to July 1, 2014, that provides for stormwater management that addresses any flow rate capacity and velocity requirements for natural or manmade channels shall satisfy the flow rate capacity and velocity requirements for natural or manmade channels if the practices are designed to (i) detain the water quality volume and to release it over 48 hours; (ii) detain and release over a 24-hour period the expected rainfall resulting from the one year, 24-hour storm; and (iii) reduce the allowable peak flow rate resulting from the 1.5-year, two-year, and 10-year 24-hour storms to a level that is less than or equal to the peak flow rate from the site assuming the site was in a good forested condition, achieved through multiplication of the forested peak flow rate by a reduction factor that is equal to the runoff volume from the site when the site was in a good forested condition divided by the runoff volume from the site in the site's proposed condition, and shall be exempt from any flow rate capacity and velocity requirements for natural or manmade channels as defined in any regulations promulgated pursuant to § 62.1-44.15:28 of the Code of Virginia (VESMA) or § 62.1-44.15:54 or 62.1-44.15:65 of the Code of Virginia (ESCL).

m. For plans approved on and after July 1, 2014, the flow rate capacity and velocity requirements of § 62.1-44.15:52 A of the Code of Virginia (ESCL) and this subdivision 19 shall be satisfied by compliance with water quantity requirements in the VESMA and attendant regulations, unless such land-disturbing activities (i) are in accordance with provisions for time limits on applicability of approved design criteria in 9VAC25-875-480 or grandfathering in 9VAC25-875-490, in which case the flow rate capacity and velocity requirements of § 62.1-44.15:52 A of the Code of Virginia (ESCL) shall apply; or (ii) are exempt pursuant to § 62.1-44.15:34 G 2 of the Code of Virginia (VESMA).

n. Compliance with the water quantity minimum standards set out in 9VAC25-875-600 shall be deemed to satisfy the requirements of this subdivision 19.

Statutory Authority

§ 62.1-44.15:28 of the Code of Virginia.

Historical Notes

Derived from Virginia Register Volume 40, Issue 8, eff. July 1, 2024.

Article 3
Water Quantity and Water Quality Technical Criteria

9VAC25-875-570. Applicability.

In accordance with the board's authority and except as provided in 9VAC25-875-490, this article establishes the minimum technical criteria that shall be employed to protect the quality and quantity of state waters from the potential harm of unmanaged stormwater runoff resulting from land-disturbing activities.

Statutory Authority

§ 62.1-44.15:28 of the Code of Virginia.

Historical Notes

Derived from Virginia Register Volume 40, Issue 8, eff. July 1, 2024.

9VAC25-875-580. Water quality design criteria requirements.

A. In order to protect the quality of state waters and to control the discharge of stormwater pollutants from regulated activities, the following minimum design criteria and statewide standards for stormwater management shall be applied to the site.

1. New development. The total phosphorus load of new development projects shall not exceed 0.41 pounds per acre per year, as calculated pursuant to 9VAC25-875-590.

2. Development on prior developed lands.

a. For land-disturbing activities disturbing greater than or equal to one acre that result in no net increase in impervious cover from the predevelopment condition, the total phosphorus load shall be reduced at least 20% below the predevelopment total phosphorus load.

b. For regulated land-disturbing activities disturbing less than one acre that result in no net increase in impervious cover from the predevelopment condition, the total phosphorus load shall be reduced at least 10% below the predevelopment total phosphorus load.

c. For land-disturbing activities that result in a net increase in impervious cover over the predevelopment condition, the design criteria for new development shall be applied to the increased impervious area. Depending on the area of disturbance, the criteria of subdivision 2 a or 2 b of this subsection shall be applied to the remainder of the site.

d. In lieu of subdivision 2 c of this subsection, the total phosphorus load of a linear development project occurring on prior developed lands shall be reduced 20% below the predevelopment total phosphorus load.

e. The total phosphorus load shall not be required to be reduced to below the applicable standard for new development unless a more stringent standard has been established by a locality.

B. Compliance with subsection A of this section shall be determined in accordance with 9VAC25-875-590.

C. Nothing in this section shall prohibit a VESMP authority from establishing more stringent water quality design criteria requirements in accordance with § 62.1-44.15:33 of the Code of Virginia.

Statutory Authority

§ 62.1-44.15:28 of the Code of Virginia.

Historical Notes

Derived from Virginia Register Volume 40, Issue 8, eff. July 1, 2024.

9VAC25-875-590. Water quality compliance.

A. Compliance with the water quality design criteria set out in subdivisions A 1 and A 2 of 9VAC25-875-580 shall be determined by utilizing the Virginia Runoff Reduction Method or another equivalent methodology that is approved by the department.

B. The BMPs listed in this subsection are approved for use as necessary to effectively reduce the phosphorus load and runoff volume in accordance with the Virginia Runoff Reduction Method. Other approved BMPs found through the Virginia Stormwater BMP Clearinghouse may also be utilized. Design specifications and the pollutant removal efficiencies for all approved BMPs are found through the Virginia Stormwater BMP Clearinghouse.

1. Vegetated Roof (Version 2.3, March 1, 2011);

2. Rooftop Disconnection (Version 1.9, March 1, 2011);

3. Rainwater Harvesting (Version 1.9.5, March 1, 2011);

4. Soil Amendments (Version 1.8, March 1, 2011);

5. Permeable Pavement (Version 1.8, March 1, 2011);

6. Grass Channel (Version 1.9, March 1, 2011);

7. Bioretention (Version 1.9, March 1, 2011);

8. Infiltration (Version 1.9, March 1, 2011);

9. Dry Swale (Version 1.9, March 1, 2011);

10. Wet Swale (Version 1.9, March 1, 2011);

11. Sheet Flow to Filter/Open Space (Version 1.9, March 1, 2011);

12. Extended Detention Pond (Version 1.9, March 1, 2011);

13. Filtering Practice (Version 1.8, March 1, 2011);

14. Constructed Wetland (Version 1.9, March 1, 2011); and

15. Wet Pond (Version 1.9, March 1, 2011).

C. Nonproprietary BMPs differing from those listed in subsection B of this section shall be reviewed and approved by the director in accordance with procedures established by the department.

D. Proprietary BMPs listed through the Virginia Stormwater BMP Clearinghouse are approved for use in accordance with the Virginia Runoff Reduction Method. Any proprietary BMP approved for use after July 1, 2020, must meet the requirements of § 62.1-44.15:28 A 9 of the Code of Virginia.

E. A VESMP authority may establish limitations on the use of specific BMPs in accordance with § 62.1-44.15:33 of the Code of Virginia.

F. The VESMP authority or department as the VSMP authority shall have the discretion to allow for application of the design criteria to each drainage area of the site. However, where a site drains to more than one HUC, the pollutant load reduction requirements shall be applied independently within each HUC unless reductions are achieved in accordance with a comprehensive watershed stormwater management plan in accordance with 9VAC25-875-660.

G. Offsite alternatives where allowed in accordance with 9VAC25-875-610 may be utilized to meet the design criteria of subsection A of 9VAC25-875-580.

H. Any publicly owned treatment works that is permitted under the watershed general VPDES permit pursuant to § 62.1-44.19:14 of the Code of Virginia and is constructing or expanding the treatment works, wastewater collection system, or other facility used for public wastewater utility operations may, in accordance with § 62.1-44.19:21.2 C of the Code of Virginia, permanently retire a portion of the publicly owned treatment works' wasteload allocation to meet the design criteria of subsection A of 9VAC25-875-580. Notice shall be given by such applicant to the VESMP authority and to the department.

Statutory Authority

§ 62.1-44.15:28 of the Code of Virginia.

Historical Notes

Derived from Virginia Register Volume 40, Issue 8, eff. July 1, 2024.

9VAC25-875-600. Water quantity.

A. Channel protection and flood protection shall be addressed in accordance with the minimum standards set out in this section, which are established pursuant to the requirements of § 62.1-44.15:28 of the Code of Virginia or as permitted in accordance with § 62.1-44.15:27.2 of the Code of Virginia. Nothing in this section shall prohibit a locality's VESMP authority from establishing a more stringent standard in accordance with § 62.1- 44.15:33 of the Code of Virginia especially where more stringent requirements are necessary to address total maximum daily load requirements or to protect exceptional state waters. Compliance with the minimum standards set out in this section shall be deemed to satisfy the requirements of subdivision 19 of 9VAC25-875-560.

B. Channel protection. Concentrated stormwater flow shall be released into a stormwater conveyance system and shall meet the criteria in subdivision 1, 2, or 3 of this subsection, where applicable, from the point of discharge to a point to the limits of analysis in subdivision 4 of this subsection.

1. Manmade stormwater conveyance systems. When stormwater from a development is discharged to a manmade stormwater conveyance system, following the land-disturbing activity, either:

a. The manmade stormwater conveyance system shall convey the post-development peak flow rate from the two-year 24-hour storm event without causing erosion of the system. Detention of stormwater or downstream improvements may be incorporated into the approved land-disturbing activity to meet this criterion, at the discretion of the VESMP authority or department as the VSMP authority; or

b. The peak discharge requirements for concentrated stormwater flow to natural stormwater conveyance systems in subdivision 3 of this subsection shall be met.

2. Restored stormwater conveyance systems. When stormwater from a development is discharged to a restored stormwater conveyance system that has been restored using natural design concepts, following the land-disturbing activity, either:

a. The development shall be consistent, in combination with other stormwater runoff, with the design parameters of the restored stormwater conveyance system that is functioning in accordance with the design objectives; or

b. The peak discharge requirements for concentrated stormwater flow to natural stormwater conveyance systems in subdivision 3 of this subsection shall be met.

3. Natural stormwater conveyance systems. When stormwater from a development is discharged to a natural stormwater conveyance system, the maximum peak flow rate from the one-year 24-hour storm following the land-disturbing activity shall be calculated either:

a. In accordance with the following methodology:

Q_Developed ≤ I.F.*(Q_{Pre-developed}* RV_{Pre-Developed})/RV_Developed

Under no condition shall Q_Developed be greater than Q_{Pre-Developed} nor shall Q_Developed be required to be less than that calculated in the equation (Q_Forest * RV_Forest)/RV_Developed; where

I.F. (Improvement Factor) equals 0.8 for sites > 1 acre or 0.9 for sites ≤ 1 acre.

Q_Developed = The allowable peak flow rate of runoff from the developed site.

RV_Developed = The volume of runoff from the site in the developed condition.

Q_{Pre-Developed} = The peak flow rate of runoff from the site in the pre-developed condition.

RV_{Pre-Developed} = The volume of runoff from the site in pre-developed condition.

Q_Forest = The peak flow rate of runoff from the site in a forested condition.

RV_Forest = The volume of runoff from the site in a forested condition; or

b. In accordance with another methodology that is demonstrated by the VESMP authority to achieve equivalent results and is approved by the department.

4. Limits of analysis. Unless subdivision 3 of this subsection is utilized to show compliance with the channel protection criteria, stormwater conveyance systems shall be analyzed for compliance with channel protection criteria to a point where either:

a. Based on land area, the site's contributing drainage area is less than or equal to 1.0% of the total watershed area; or

b. Based on peak flow rate, the site's peak flow rate from the one-year 24-hour storm is less than or equal to 1.0% of the existing peak flow rate from the one-year 24-hour storm prior to the implementation of any stormwater quantity control measures.

C. Flood protection. Concentrated stormwater flow shall be released into a stormwater conveyance system and shall meet one of the following criteria as demonstrated by use of acceptable hydrologic and hydraulic methodologies:

1. Concentrated stormwater flow to stormwater conveyance systems that currently do not experience localized flooding during the 10-year 24-hour storm event: The point of discharge releases stormwater into a stormwater conveyance system that, following the land-disturbing activity, confines the post-development peak flow rate from the 10-year 24-hour storm event within the stormwater conveyance system. Detention of stormwater or downstream improvements may be incorporated into the approved land-disturbing activity to meet this criterion, at the discretion of the VESMP authority.

2. Concentrated stormwater flow to stormwater conveyance systems that currently experience localized flooding during the 10-year 24-hour storm event: The point of discharge either:

a. Confines the post-development peak flow rate from the 10-year 24-hour storm event within the stormwater conveyance system to avoid the localized flooding. Detention of stormwater or downstream improvements may be incorporated into the approved land-disturbing activity to meet this criterion at the discretion of the VESMP authority or department as the VSMP authority; or

b. Releases a post-development peak flow rate for the 10-year 24-hour storm event that is less than the predevelopment peak flow rate from the 10-year 24-hour storm event. Downstream stormwater conveyance systems do not require any additional analysis to show compliance with flood protection criteria if this option is utilized.

3. Limits of analysis. Unless subdivision 2 b of this subsection is utilized to comply with the flood protection criteria, stormwater conveyance systems shall be analyzed for compliance with flood protection criteria to a point where:

a. The site's contributing drainage area is less than or equal to 1.0% of the total watershed area draining to a point of analysis in the downstream stormwater conveyance system;

b. Based on peak flow rate, the site's peak flow rate from the 10-year 24-hour storm event is less than or equal to 1.0% of the existing peak flow rate from the 10-year 24-hour storm event prior to the implementation of any stormwater quantity control measures; or

c. The stormwater conveyance system enters a mapped floodplain or other flood-prone area, adopted by ordinance, of any locality.

D. Increased volumes of sheet flow resulting from pervious or disconnected impervious areas or from physical spreading of concentrated flow through level spreaders shall be identified and evaluated for potential impacts on down-gradient properties or resources. Increased volumes of sheet flow that will cause or contribute to erosion, sedimentation, or flooding of down gradient properties or resources shall be diverted to a stormwater management facility or a stormwater conveyance system that conveys the runoff without causing down-gradient erosion, sedimentation, or flooding. If all runoff from the site is sheet flow and the conditions of this subsection are met, no further water quantity controls are required.

E. For purposes of computing predevelopment runoff, all pervious lands on the site shall be assumed to be in good hydrologic condition in accordance with the U.S. Department of Agriculture's Natural Resources Conservation Service (NRCS) standards, regardless of conditions existing at the time of computation. Predevelopment runoff calculations utilizing other hydrologic conditions may be utilized provided that it is demonstrated to and approved by the VESMP authority that actual site conditions warrant such considerations.

F. Predevelopment and post-development runoff characteristics and site hydrology shall be verified by site inspections, topographic surveys, available soil mapping or studies, and calculations consistent with good engineering practices. Guidance provided in the Virginia Stormwater Management Handbook and the Virginia Stormwater BMP Clearinghouse shall be considered appropriate practices.

Statutory Authority

§ 62.1-44.15:28 of the Code of Virginia.

Historical Notes

Derived from Virginia Register Volume 40, Issue 8, eff. July 1, 2024.

9VAC25-875-610. Offsite compliance options.

A. No offsite option shall be used in contravention of local water quality-based limitations (i) determined pursuant to subsection B of § 62.1-44.19:14 of the Code of Virginia, (ii) adopted pursuant to § 62.1-44.15:33 of the Code of Virginia or other applicable authority, (iii) deemed necessary to protect public water supplies from demonstrated adverse nutrient impacts, or (iv) as otherwise may be established or approved by the department. Where such a limitation exists, offsite options may be used provided that such options do not preclude or impair compliance with the local limitation.

B. Unless prohibited by subsection A of this section, a VESMP authority or the department as the VSMP authority:

1. May allow the use of offsite options for compliance with water quality and water quantity technical criteria established pursuant to § 62.1-44.15:28 of the Code of Virginia, in whole or in part; and

2. Shall allow the use of nutrient credits for compliance with the water quality technical criteria when:

a. Less than five acres of land will be disturbed;

b. The phosphorous water quality reduction requirement is less than 10 pounds per year; or

c. It is demonstrated to the satisfaction of the VESMP authority or department as the VSMP authority that (i) alternative site designs have been considered that may accommodate onsite best management practices, (ii) onsite best management practices have been considered in alternative site designs to the maximum extent practicable, (iii) appropriate onsite best management practices will be implemented, and (iv) compliance with quality technical criteria cannot practicably be met onsite. The requirements of clauses (i) through (iv) of this subdivision shall be deemed to have been met if it is demonstrated that onsite control of at least 75% of the required phosphorous water quality reduction will be achieved.

C. The VESMP authority or department as the VSMP authority shall require that offsite options approved by the department or applicable state board achieve the necessary phosphorous water quality reductions prior to the commencement of the land-disturbing activity. In the case of a phased project, the land disturber may acquire or achieve the offsite nutrient reductions prior to the commencement of each phase of the land-disturbing activity in an amount sufficient for each such phase.

D. Nutrient credits shall not be used to address water quantity technical criteria.

E. Nutrient credits shall be generated in the same or adjacent fourth order subbasin, as defined by the hydrologic unit boundaries of the National Watershed Boundary Dataset, as the land-disturbing activity. If no credits are available within these subbasins when the VESMP or department as the VSMP authority accepts the final site design, credits available within the same tributary may be used. The following requirements apply to the use of nutrient credits:

1. Documentation of the acquisition of nutrient credits shall be provided to the VESMP authority and the department or the department as the VSMP authority in a certification from the credit provider documenting the number of phosphorus nutrient credits acquired and the associated ratio of nitrogen nutrient credits at the credit-generating entity.

2. Application fees are provided in Certification of Nonpoint Source Nutrient Credits (9VAC25-900). Fees shall be deposited into the Virginia Stormwater Management Fund established by § 62.1-44.15:29 of the Code of Virginia.

3. For that portion of a site's compliance with water quality technical criteria being obtained through nutrient credits, the land disturber shall (i) comply with a one-to-one ratio of the nutrient credits to the site's remaining post-development nonpoint nutrient runoff compliance requirement being met by credit use and (ii) use credits certified as perpetual credits pursuant to Article 4.02 (§ 62.1-44.19:12 et seq.) of Chapter 3.1 of Title 62.1 of the Code of Virginia.

4. A VESMP or the department as the VSMP authority shall allow the full or partial substitution of perpetual nutrient credits for existing onsite nutrient controls when (i) the nutrient credits will compensate for 10 or fewer pounds of the annual phosphorous requirement associated with the original land-disturbing activity or (ii) existing onsite controls are not functioning as anticipated after reasonable attempts to comply with applicable maintenance agreements or requirements and the use of nutrient credits will account for the deficiency. Upon determination by the VESMP or department that the conditions established by clause (i) or (ii) of this subdivision have been met, the party responsible for maintenance shall be released from maintenance obligations related to the onsite phosphorous controls for which the nutrient credits are substituted.

F. Exchange of a credit released by the department is subject to the provisions of § 62.1-44.15:35, 62.1-44.19:15, or 62.1-44.19:21 of the Code of Virginia. Where necessary to ensure compliance with local water quality requirements, the exchange of a credit released by the department is conditioned by 9VAC25-900-91 B and C.

Statutory Authority

§ 62.1-44.15:28 of the Code of Virginia.

Historical Notes

Derived from Virginia Register Volume 40, Issue 8, eff. July 1, 2024.

9VAC25-875-620. Design storms and hydrologic methods.

A. Unless otherwise specified, the prescribed design storms are the one-year, two-year, and 10-year 24-hour storms using the site-specific rainfall precipitation frequency data recommended by the U.S. National Oceanic and Atmospheric Administration (NOAA) Atlas 14. Partial duration time series shall be used for the precipitation data.

B. Unless otherwise specified, all hydrologic analyses shall be based on the existing watershed characteristics and how the ultimate development condition of the subject project will be addressed.

C. The U.S. Department of Agriculture's Natural Resources Conservation Service (NRCS) synthetic 24-hour rainfall distribution and models, including TR-55 and TR-20; hydrologic and hydraulic methods developed by the U.S. Army Corps of Engineers; or other standard hydrologic and hydraulic methods shall be used to conduct the analyses described in this part.

D. For drainage areas of 200 acres or less, the VESMP authority or department as the VSMP authority may allow for the use of the Rational Method for evaluating peak discharges.

E. For drainage areas of 200 acres or less, the VESMP authority or department as the VSMP authority may allow for the use of the Modified Rational Method for evaluating volumetric flows to stormwater conveyances.

Statutory Authority

§ 62.1-44.15:28 of the Code of Virginia.

Historical Notes

Derived from Virginia Register Volume 40, Issue 8, eff. July 1, 2024.

9VAC25-875-630. Stormwater harvesting.

In accordance with § 62.1-44.15:28 of the Code of Virginia, stormwater harvesting is encouraged for the purposes of landscape irrigation systems, fire protection systems, flushing water closets and urinals, and other water handling systems to the extent such systems are consistent with federal, state, and local regulations.

Statutory Authority

§ 62.1-44.15:28 of the Code of Virginia.

Historical Notes

Derived from Virginia Register Volume 40, Issue 8, eff. July 1, 2024.

9VAC25-875-640. Linear development projects.

Linear development projects shall control post-development stormwater runoff in accordance with a site-specific stormwater management plan or a comprehensive watershed stormwater management plan developed in accordance with this chapter.

Statutory Authority

§ 62.1-44.15:28 of the Code of Virginia.

Historical Notes

Derived from Virginia Register Volume 40, Issue 8, eff. July 1, 2024.

9VAC25-875-650. Stormwater management impoundment structures or facilities.

A. Stormwater management wet ponds and extended detention ponds that are not covered by the Impounding Structure Regulations (4VAC50-20) shall, at a minimum, be engineered for structural integrity for the 100-year storm event.

B. Construction of stormwater management impoundment structures or facilities may occur in karst areas only after a study of the geology and hydrology of the area has been conducted to determine the presence or absence of karst features that may be impacted by stormwater runoff and BMP placement.

C. Discharge of stormwater runoff to a karst feature shall meet the water quality criteria set out in 9VAC25-875-580 and the water quantity criteria set out in 9VAC25-875-600. Permanent stormwater management impoundment structures or facilities shall only be constructed in karst features after completion of a geotechnical investigation that identifies any necessary modifications to the BMP to ensure its structural integrity and maintain its water quality and quantity efficiencies. The person responsible for the land-disturbing activity is encouraged to screen for known existence of heritage resources in the karst features.

Statutory Authority

§ 62.1-44.15:28 of the Code of Virginia.

Historical Notes

Derived from Virginia Register Volume 40, Issue 8, eff. July 1, 2024.

9VAC25-875-660. Comprehensive stormwater management plans.

A VESMP authority may develop comprehensive stormwater management plans to be approved by the department that meet the water quality objectives, quantity objectives, or both of this part:

1. Such plans shall ensure that offsite reductions equal to or greater than those that would be required on each contributing site are achieved within the same HUC or within another locally designated watershed. Pertaining to water quantity objectives, the plan may provide for implementation of a combination of channel improvement, stormwater detention, or other measures that are satisfactory to the locality's VESMP authority to prevent downstream erosion and flooding.

2. If the land use assumptions upon which the plan was based change or if any other amendments are deemed necessary by the locality's VESMP authority, such authority shall provide plan amendments to the department for review and approval.

3. During the plan's implementation, the locality's VESMP authority shall document nutrient reductions credited to the BMPs specified in the plan.

4. State agencies and federal entities may develop comprehensive stormwater management plans and may participate in locality-developed comprehensive stormwater management plans where practicable and permitted by the locality's VESMP authority.

Statutory Authority

§ 62.1-44.15:28 of the Code of Virginia.

Historical Notes

Derived from Virginia Register Volume 40, Issue 8, eff. July 1, 2024.

Article 4
Water Quantity and Water Quality Technical Criteria for Grandfathered Projects and Time Limits of Applicability Projects

9VAC25-875-670. Definitions.

For the purposes of this article only, the following words and terms have the following meanings unless the context clearly indicates otherwise:

"Aquatic bench" means a 10-foot to 15-foot wide bench around the inside perimeter of a permanent pool that ranges in depth from zero to 12 inches. Vegetated with emergent plants, the bench augments pollutant removal, provides habitats, conceals trash and water level fluctuations, and enhances safety.

"Average land cover condition" means a measure of the average amount of impervious surfaces within a watershed, assumed to be 16% or a calculated watershed-specific value for the average land cover condition as approved by the Chesapeake Bay Local Assistance Board prior to September 13, 2011.

"Bioretention basin" means a water quality BMP engineered to filter the water quality volume (i) through an engineered planting bed consisting of a vegetated surface layer (vegetation, mulch, ground cover), planting soil, and sand bed and (ii) into the in-situ material.

"Bioretention filter" means a bioretention basin with the addition of a sand filter collector pipe system beneath the planting bed.

"Constructed wetlands" means areas intentionally designed and created to emulate the water quality improvement function of wetlands for the primary purpose of removing pollutants from stormwater.

"Development" means a tract of land developed or to be developed as a unit under single ownership or unified control that is to be used for any business or industrial purpose or is to contain three or more residential dwelling units.

"Grassed swale" means an earthen conveyance system that is broad and shallow with erosion resistant grasses and check dams, engineered to remove pollutants from stormwater runoff by filtration through grass and infiltration into the soil.

"Infiltration facility" means a stormwater management facility that temporarily impounds runoff and discharges it via infiltration through the surrounding soil. While an infiltration facility may also be equipped with an outlet structure to discharge impounded runoff, such discharge is normally reserved for overflow and other emergency conditions. Since an infiltration facility impounds runoff only temporarily, it is normally dry during nonrainfall periods. Infiltration basin, infiltration trench, infiltration dry well, and porous pavement shall be considered infiltration facilities.

"Layout" means a conceptual drawing sufficient to provide for the specified stormwater management facilities required at the time of approval.

"Nonpoint source pollutant runoff load" or "pollutant discharge" means the average amount of a particular pollutant measured in pounds per year, delivered in a diffuse manner by stormwater runoff.

"Planning area" means a designated portion of the parcel on which the land development project is located. Planning areas shall be established by delineation on a master plan. Once established, planning areas shall be applied consistently for all future projects.

"Sand filter" means a contained bed of sand that acts to filter the first flush of runoff. The runoff is then collected beneath the sand bed and conveyed to an adequate discharge point or infiltrated into the in-situ soils.

"Shallow marsh" means a zone within a stormwater extended detention basin that exists from the surface of the normal pool to a depth of six to 18 inches, and has a large surface area and, therefore, requires a reliable source of baseflow, groundwater supply, or a sizeable drainage area to maintain the desired water surface elevations to support emergent vegetation.

"Stormwater detention basin" or "detention basin" means a stormwater management facility that temporarily impounds runoff and discharges it through a hydraulic outlet structure to a downstream conveyance system. While a certain amount of outflow may also occur via infiltration through the surrounding soil, such amounts are negligible when compared to the outlet structure discharge rates and are, therefore, not considered in the facility's design. Since a detention facility impounds runoff only temporarily, it is normally dry during nonrainfall periods.

"Stormwater extended detention basin" or "extended detention basin" means a stormwater management facility that temporarily impounds runoff and discharges it through a hydraulic outlet structure over a specified period of time to a downstream conveyance system for the purpose of water quality enhancement or stream channel erosion control. While a certain amount of outflow may also occur via infiltration through the surrounding soil, such amounts are negligible when compared to the outlet structure discharge rates and, therefore, are not considered in the facility's design. Since an extended detention basin impounds runoff only temporarily, it is normally dry during nonrainfall periods.

"Stormwater extended detention basin-enhanced" or "extended detention basin-enhanced" means an extended detention basin modified to increase pollutant removal by providing a shallow marsh in the lower stage of the basin.

"Stormwater retention basin" or "retention basin" means a stormwater management facility that includes a permanent impoundment, or normal pool of water, for the purpose of enhancing water quality and, therefore, is normally wet even during nonrainfall periods. Storm runoff inflows may be temporarily stored above this permanent impoundment for the purpose of reducing flooding or stream channel erosion.

"Stormwater retention basin I" or "retention basin I" means a retention basin with the volume of the permanent pool equal to three times the water quality volume.

"Stormwater retention basin II" or "retention basin II" means a retention basin with the volume of the permanent pool equal to four times the water quality volume.

"Stormwater retention basin III" or "retention basin III" means a retention basin with the volume of the permanent pool equal to four times the water quality volume with the addition of an aquatic bench.

"Vegetated filter strip" means a densely vegetated section of land engineered to accept runoff as overland sheet flow from upstream development. It shall adopt any natural vegetated form, from grassy meadow to small forest. The vegetative cover facilitates pollutant removal through filtration, sediment deposition, infiltration, and absorption and is dedicated for that purpose.

"Water quality volume" means the volume equal to the first 1/2-inch of runoff multiplied by the impervious surface of the land development project.

Statutory Authority

§ 62.1-44.15:28 of the Code of Virginia.

Historical Notes

Derived from Virginia Register Volume 40, Issue 8, eff. July 1, 2024.

9VAC25-875-680. Applicability.

This part specifies the technical criteria for regulated land-disturbing activities that are not subject to the technical criteria of Article 3 (9VAC25-875-570 et seq.) of this part in accordance with 9VAC25-875-490.

Statutory Authority

§ 62.1-44.15:28 of the Code of Virginia.

Historical Notes

Derived from Virginia Register Volume 40, Issue 8, eff. July 1, 2024.

9VAC25-875-690. General.

A. Determination of flooding and channel erosion impacts to receiving streams due to land-disturbing activities shall be measured at each point of discharge from the land disturbance and such determination shall include any runoff from the balance of the watershed that also contributes to that point of discharge.

B. The specified design storms shall be defined as either a 24-hour storm using the rainfall distribution recommended by the U.S. Department of Agriculture's Natural Resources Conservation Service (NRCS) when using NRCS methods or as the storm of critical duration that produces the greatest required storage volume at the site when using a design method such as the Modified Rational Method.

C. For purposes of computing runoff, all pervious lands in the site shall be assumed prior to development to be in good condition (if the lands are pastures, lawns, or parks), with good cover (if the lands are woods), or with conservation treatment (if the lands are cultivated); regardless of conditions existing at the time of computation.

D. Construction of stormwater management facilities or modifications to channels shall comply with all applicable laws, regulations, and ordinances. Evidence of approval of all necessary permits shall be presented.

E. Impounding structures that are not covered by the Impounding Structure Regulations (4VAC50-20) shall be engineered for structural integrity during the 100-year storm event.

F. Predevelopment and post-development runoff rates shall be verified by calculations that are consistent with good engineering practices.

G. Outflows from a stormwater management facility or stormwater conveyance system shall be discharged to an adequate channel.

H. Proposed residential, commercial, or industrial subdivisions shall apply these stormwater management criteria to the land disturbance as a whole. Individual lots in new subdivisions shall not be considered separate land-disturbing activities, but rather the entire subdivision shall be considered a single land development project. Hydrologic parameters shall reflect the ultimate land disturbance and shall be used in all engineering calculations.

I. All stormwater management facilities shall have an inspection and maintenance plan that identifies the owner and the responsible party for carrying out the inspection and maintenance plan.

J. Construction of stormwater management impoundment structures within a Federal Emergency Management Agency (FEMA) designated 100-year floodplain shall be avoided whenever possible. When this is unavoidable, all stormwater management facility construction shall be in compliance with all applicable regulations under the National Flood Insurance Program (44 CFR Part 59).

K. Natural channel characteristics shall be preserved to the maximum extent practicable.

L. Land-disturbing activities shall comply with the ESCL or VESMA, as applicable, and attendant regulations.

M. Flood control and stormwater management facilities that drain or treat water from multiple development projects or from a significant portion of a watershed may be allowed in Resource Protection Areas defined in the Chesapeake Bay Preservation Act provided such facilities are allowed and constructed in accordance with the VESMA and this chapter, and provided that (i) the local government has conclusively established that the location of the facility within the Resource Protection Area is the optimum location; (ii) the size of the facility is the minimum necessary to provide necessary flood control, stormwater treatment, or both; (iii) the facility must be consistent with a comprehensive stormwater management plan developed and approved in accordance with 9VAC25-875-660 or with a stormwater management plan that has been approved prior to July 1, 2012, by the department, the Chesapeake Bay Local Assistance Board prior to its abolishment on July 1, 2012, or the Board of Conservation and Recreation; (iv) all applicable permits for construction in state or federal waters must be obtained from the appropriate state and federal agencies; (v) approval must be received from the local government prior to construction; and (vi) routine maintenance is allowed to be performed on such facilities to ensure that they continue to function as designed. It is not the intent of this subsection to allow a best management practice that collects and treats runoff from only an individual lot or some portion of the lot to be located within a Resource Protection Area.

Statutory Authority

§ 62.1-44.15:28 of the Code of Virginia.

Historical Notes

Derived from Virginia Register Volume 40, Issue 8, eff. July 1, 2024.

9VAC25-875-700. Water quality.

A. Compliance with the water quality criteria may be achieved by applying the performance-based criteria or the technology-based criteria to either the site or a planning area.

B. Performance-based criteria. For land-disturbing activities, the calculated post-development nonpoint source pollutant runoff load shall be compared to the calculated predevelopment load based upon the average land cover condition or the existing site condition. A BMP shall be located, designed, and maintained to achieve the target pollutant removal efficiencies specified in Table 1 of this section to effectively reduce the pollutant load to the required level based upon the following four applicable land development situations for which the performance criteria apply:

1. Situation 1 consists of land-disturbing activities where the existing percent impervious cover is less than or equal to the average land cover condition and the proposed improvements will create a total percent impervious cover that is less than the average land cover condition.

Requirement: No reduction in the after disturbance pollutant discharge is required.

2. Situation 2 consists of land-disturbing activities where the existing percent impervious cover is less than or equal to the average land cover condition and the proposed improvements will create a total percent impervious cover that is greater than the average land cover condition.

Requirement: The pollutant discharge after disturbance shall not exceed the existing pollutant discharge based on the average land cover condition.

3. Situation 3 consists of land-disturbing activities where the existing percent impervious cover is greater than the average land cover condition.

Requirement: The pollutant discharge after disturbance shall not exceed (i) the pollutant discharge based on existing conditions less 10% or (ii) the pollutant discharge based on the average land cover condition, whichever is greater.

4. Situation 4 consists of land-disturbing activities where the existing percent impervious cover is served by an existing stormwater management BMP that addresses water quality.

Requirement: The pollutant discharge after disturbance shall not exceed the existing pollutant discharge based on the existing percent impervious cover while served by the existing BMP. The existing BMP shall be shown to have been designed and constructed in accordance with proper design standards and specifications and to be in proper functioning condition.

C. Technology-based criteria. For land-disturbing activities, the post-developed stormwater runoff from the impervious cover shall be treated by an appropriate BMP as required by the post-developed condition percent impervious cover as specified in Table 1 of this section. The selected BMP shall be located, designed, and maintained to perform at the target pollutant removal efficiency specified in Table 1 or those found in 9VAC25-875-590.

D. Design standards and specifications for the BMPs in Table 1 of this section that meet the required target pollutant removal efficiency are available in the Virginia Stormwater Management Handbook. Other approved BMPs available through the Virginia Stormwater BMP Clearinghouse may also be utilized.

E. The VESMP authority or department as the VSMP authority may allow the use of offsite nutrient credits under Article 4 (9VAC25-875-670 et seq.) of this part in accordance with 9VAC25-875-610.

Statutory Authority

§ 62.1-44.15:28 of the Code of Virginia.

Historical Notes

Derived from Virginia Register Volume 40, Issue 8, eff. July 1, 2024.

9VAC25-875-710. Stream channel erosion.

A. Properties and receiving waterways downstream of any land-disturbing activity shall be protected from erosion and damage due to changes in runoff rate of flow and hydrologic characteristics, including changes in volume, velocity, frequency, duration, and peak flow rate of stormwater runoff in accordance with the minimum design standards set out in this section.

B. The VESMP authority or department as the VSMP authority shall require compliance with subdivision 19 of 9VAC25-875-560.

C. The locality's VESMP authority may determine that some watersheds or receiving stream systems require enhanced criteria in order to address the increased frequency of bankfull flow conditions (top of bank) brought on by land-disturbing activities or where more stringent requirements are necessary to address total maximum daily load requirements or to protect exceptional waters. Therefore, in lieu of the reduction of the two-year post-developed peak rate of runoff as required in subsection B of this section, the land development project being considered shall provide 24-hour extended detention of the runoff generated by the one-year, 24-hour duration storm.

D. In addition to subsections B and C of this section, a locality's VESMP authority by local ordinance may in accordance with § 62.1-44.15:33 of the Code of Virginia, or the board by state regulation may adopt more stringent channel analysis criteria or design standards to ensure that the natural level of channel erosion, to the maximum extent practicable, will not increase due to the land-disturbing activities. These criteria may include the following:

1. Criteria and procedures for channel analysis and classification.

2. Procedures for channel data collection.

3. Criteria and procedures for the determination of the magnitude and frequency of natural sediment transport loads.

4. Criteria for the selection of proposed natural or manmade channel linings.

Statutory Authority

§ 62.1-44.15:28 of the Code of Virginia.

Historical Notes

Derived from Virginia Register Volume 40, Issue 8, eff. July 1, 2024.

9VAC25-875-720. Flooding.

A. Downstream properties and waterways shall be protected from damages from localized flooding due to changes in runoff rate of flow and hydrologic characteristics, including changes in volume, velocity, frequency, duration, and peak flow rate of stormwater runoff in accordance with the minimum design standards set out in this section.

B. The 10-year post-developed peak rate of runoff from the development site shall not exceed the 10-year predeveloped peak rate of runoff.

C. In lieu of subsection B of this section, localities may, by ordinance in accordance with § 62.1-44.15:33 of the Code of Virginia, adopt alternate design criteria based upon geographic, land use, topographic, geologic factors, or other downstream conveyance factors as appropriate.

D. Linear development projects shall not be required to control post-developed stormwater runoff for flooding, except in accordance with a watershed or regional stormwater management plan.

Statutory Authority

§ 62.1-44.15:28 of the Code of Virginia.

Historical Notes

Derived from Virginia Register Volume 40, Issue 8, eff. July 1, 2024.

9VAC25-875-730. Regional (watershed-wide) stormwater management plans.

Water quality requirements and where allowed, water quantity requirements, may be achieved in accordance with sections 9VAC25-875-610 and 9VAC25-875-660.

Statutory Authority

§ 62.1-44.15:28 of the Code of Virginia.

Historical Notes

Derived from Virginia Register Volume 40, Issue 8, eff. July 1, 2024.

Article 5
Criteria for Land-Disturbing Activities in Chesapeake Bay Preservation Areas

9VAC25-875-740. Land-disturbing activities in Chesapeake Bay Preservation Areas.

A. In order to protect the quality of state waters and to control the discharge of stormwater pollutants from land-disturbing activities, runoff associated with land-disturbing activities in Chesapeake Bay Preservation Areas that are equal to or greater than 2,500 square feet but less than one acre shall be regulated by localities subject to the Chesapeake Bay Preservation Act or, in the case of state and federal agency projects, the department. In regulating such land-disturbing activities in accordance with subsection B of this section, localities shall have the same authority and responsibilities as set forth for VESCP and VESMP authorities.

B. After June 30, 2014, such land-disturbing activities shall not require completion of a registration statement or require coverage under the General VPDES Permit for Discharges of Stormwater from Construction Activities but shall be subject to the following technical criteria and program and administrative requirements unless excluded under 9VAC25-875-90 and 9VAC25-875-280:

1. An erosion and sediment control plan consistent with the requirements of 9VAC25-875-550 must be designed and implemented during land-disturbing activities. Prior to land disturbance, this plan must be approved by either the VESCP or VESMP authority in accordance with this chapter;

2. A stormwater management plan consistent with the requirements of 9VAC25-875-510 must be designed and implemented during the land-disturbing activity. The stormwater management plan shall be developed and submitted in accordance with 9VAC25-875-510. Prior to land disturbance, this plan must be approved by the VESCP or VESMP authority;

3. Exceptions may be requested in accordance with 9VAC25-875-170;

4. Long-term maintenance of stormwater management facilities shall be provided for and conducted in accordance with 9VAC25-875-535;

5. Water quality design criteria in 9VAC25-875-580 shall be applied to the site;

6. Water quality compliance shall be achieved in accordance with 9VAC25-875-590;

7. Channel protection and flood protection shall be achieved in accordance with 9VAC25-875-600 or as permitted by subsection B of 9VAC25-875-750;

8. Offsite compliance options in accordance with 9VAC25-875-610 shall be available to land-disturbing activities in Chesapeake Bay Preservation Areas that are equal to or greater than 2,500 square feet but less than one acre; and

9. Such land-disturbing activities shall be subject to the design storm and hydrologic methods set out in 9VAC25-875-620, linear development controls in 9VAC25-875-640, and criteria associated with stormwater impoundment structures or facilities in 9VAC25-875-650.

Statutory Authority

§ 62.1-44.15:28 of the Code of Virginia.

Historical Notes

Derived from Virginia Register Volume 40, Issue 8, eff. July 1, 2024.

9VAC25-875-750. Land-disturbing activities in Chesapeake Bay Preservation Areas in rural Tidewater localities.

A. Acceptance of signed and sealed plans in lieu of local plan review. In lieu of a local plan review or retaining a local certified plan reviewer, a rural Tidewater locality may accept plans and supporting calculations for erosion and sediment control and stormwater management for any land-disturbing activity equal to or greater than 2,500 square feet but less than one acre if the following criteria are met:

1. The plans are prepared and submitted by a professional licensed to engage in practice in the Commonwealth under Chapter 4 (§ 54.1-400 et seq.) or 22 (§ 54.1-2200 et seq.) of Title 54.1 of the Code of Virginia and who shall hold a certificate of competence in the appropriate subject area, as provided in § 62.1-44.15:30 of the Code of Virginia; and

2. The plan and supporting calculations are appropriately signed and sealed by the professional with a certification that states: "This plan is designed in accordance with applicable state law and regulations."

B. For determining the water quantity technical criteria applicable to a land disturbance equal to or greater than 2,500 square feet, but less than one acre, any rural Tidewater locality may elect to use certain tiered water quantity control standards based on the percentage of impervious cover in the watershed as provided in § 62.1-44.15:27.2 of the Code of Virginia.

C. Tiered approach to water quantity technical criteria compliance.

1. A rural Tidewater locality may adopt the following tiered approach to water quantity management based on the percent impervious cover of the watershed in accordance with this subsection for land-disturbing activities that disturb an area of 2,500 square feet or more but less than one acre:

a. For less than 5.0% impervious cover, apply the Virginia Erosion and Sediment Control Minimum Standard 19 in effect prior to July 1, 2014, for the protection of downstream properties and waterways from sediment deposition, erosion, and damage due to increases in volume, velocity, and peak flow rate of stormwater runoff for the stated frequency storm of 24-hour duration.

b. For 5.0% or more impervious cover but less than 7.5%, detain and release over a 24-hour period the expected rainfall resulting from the one year, 24-hour storm, which practices shall be exempt from any flow rate capacity and velocity requirements for natural or manmade channels.

c. For 7.5% impervious cover or more, apply the water quantity technical criteria in accordance with 9VAC25-875-600.

2. The establishment and conduct of the tiered approach by the locality pursuant to this section shall be subject to review by the department.

3. Prior to the adoption and implementation of the tiered approach to water quantity management, the local governing body shall:

a. Develop a watershed map that includes the following:

(1) The boundaries of the locality and each watershed located partially or wholly within the locality based on the most recent version of Virginia's 6th order National Watershed Boundary Dataset;

(2) The percentage of impervious cover within each watershed. Data provided by the Virginia Geographic Information Network (VGIN) shall be sufficient for the initial determination of impervious cover percentage at the time of the initial adoption of the map; and

(3) The locations at which the governing body expects or proposes that development should occur and may indicate the projected future percentage of impervious cover based on proposed development. The governing body may designate certain areas within a watershed in which it proposes that denser-than-average development shall occur and may designate environmentally sensitive areas in which the water quantity technical criteria in 9VAC25-875-600 shall apply.

b. After the watershed map has been developed, the governing body may then approve and adopt the map by a majority vote of its membership and publish it as the official watershed map of the locality. No official watershed map shall be adopted by the governing body or have any effect until it is approved by an ordinance duly passed by the governing body of the locality after a public hearing, preceded by public notice as required by § 15.2-2204 of the Code of Virginia. Within 30 days after adoption of the official watershed map, the governing body shall file the watershed map in the office of the clerk of the circuit court.

4. At least once per year, the governing body shall by majority vote make additions to or modifications of the official watershed map to reflect actual development projects. The governing body shall change the indication on the map of the impervious cover percentage within a watershed where the percentage has changed and shall update the map and supporting datasets with actual development project information, including single-family housing projects and any projects covered by the General VPDES Permit for Discharges of Stormwater from Construction Activities (9VAC25-880) and administered by the department for opt-out localities pursuant to § 62.1-44.15:27 of the Code of Virginia. The governing body may incorporate into the official watershed map the most recent VGIN data, including data on state and federal projects that are not reviewed or approved by the locality. The governing body shall keep current its impervious cover percentage for each watershed located within the locality as reflected in the official watershed map and shall make the map and such percentages available to the public.

5. The locality shall notify the department and update the official watershed map within 12 months of the approval of the development plan for any project that exceeds the percent impervious cover percentage of the watershed in which it is located and causes the impervious cover percentage for the watershed to increase such that the watershed percent impervious cover is categorized by the next higher tier pursuant to subdivision 1 of this subsection.

6. No official watershed map or its adopting or amending ordinance shall take precedence over any duly adopted zoning ordinance, comprehensive plan, or other local land-use ordinance, and in the case of a conflict, the official watershed map or ordinance shall yield to such land-use ordinance.

Statutory Authority

§ 62.1-44.15:28 of the Code of Virginia.

Historical Notes

Derived from Virginia Register Volume 40, Issue 8, eff. July 1, 2024.

Article 6
Additional Criteria and Requirements for Land-Disturbing Activities by State Agencies and Federal Entities

9VAC25-875-760. Soil erosion control and stormwater management for land-disturbing activities.

The department shall act as a VESMP where state agencies and federal entities have not submitted standards and specifications to the department for approval. When a state agency or federal entity submits a soil erosion control and stormwater management plan (ESM plan) for a project, land disturbance shall not commence until the department has reviewed and approved the plan and has issued permit coverage when it is required in accordance with § 62.1-44.15:34 of the Code of Virginia.

1. The department shall not approve an ESM plan submitted by a state agency or federal entity for a project involving a land-disturbing activity (i) in any locality that has not adopted a local program with more stringent ordinances than those of the state program or (ii) in multiple jurisdictions with separate local programs, unless the plan is consistent with the requirements of the state program.

2. The department shall not approve an ESM plan submitted by a state agency or federal entity for a project involving a land-disturbing activity in one locality with a local program with more stringent ordinances than those of the state program, unless the plan is consistent with the requirements of the local program.

3. If onsite changes occur, the state agency or federal entity shall submit an amended ESM plan to the department.

4. The state agency or federal entity responsible for the land-disturbing activity shall ensure compliance with the approved ESM plan. As necessary, the department shall provide project oversight and enforcement.

Statutory Authority

§ 62.1-44.15:28 of the Code of Virginia.

Historical Notes

Derived from Virginia Register Volume 40, Issue 8, eff. July 1, 2024.

9VAC25-875-770. State agency land-disturbing activities.

A. All state agency land-disturbing activities that are not exempt and that have commenced without an approved erosion and sediment control plan shall immediately cease until the state agency has either submitted standards and specifications for its conduct of land-disturbing activities which has been reviewed and approved by the department as being consistent with the VESMA and attendant regulations or an erosion and sediment control plan has been submitted to and approved by the department. A formal Notice of Plan Requirement will be sent to the state agency under whose purview the project lies since that agency is responsible for compliance with the State Water Control Law and this chapter.

B. Where inspections by department personnel reveal deficiencies in carrying out an approved plan, the person responsible for carrying out the plan, as well as the state agency responsible, will be issued a notice to comply with specific actions and the deadlines that shall be met. Failure to meet the prescribed deadlines can result in the issuance of a stop work order for all land-disturbing activities on the project at the discretion of the department. The stop work order will be lifted once the required erosion and sediment control measures are in place and inspected by department staff.

C. Whenever the Commonwealth or any of its agencies fails to comply within the time provided in an appropriate final order, the director of the department may petition for compliance as follows: For violations in the Natural and Historic Resources Secretariat, to the Secretary of Natural and Historic Resources; for violations in other secretariats, to the appropriate Secretary; for violations in other state agencies, to the head of such agency. Where the petition does not achieve timely compliance, the director shall bring the matter to the Governor for resolution. The department may also pursue enforcement as provided by § 62.1-44.15:48 of the Code of Virginia and Article 5 (§ 62.1- 44.20 et seq.) of the State Water Control Law.

D. Where compliance will require the appropriation of funds, the director shall cooperate with the appropriate agency head in seeking such an appropriation; where the director determines that an emergency exists, the director shall petition the Governor for funds from the Civil Contingency Fund or other appropriate source.

Statutory Authority

§ 62.1-44.15:28 of the Code of Virginia.

Historical Notes

Derived from Virginia Register Volume 40, Issue 8, eff. July 1, 2024.

9VAC25-875-780. Stormwater management permit applications.

A. Approval of a permit application (registration statement) for a land-disturbing activity by a state agency or federal entity shall be subject to the following conditions:

1. The state agency or federal entity shall comply with all applicable requirements of the permit (9VAC25-880) and shall certify that all land clearing, construction, land development, and drainage will be done according to the permit.

2. The land development shall be conducted only within the area specified in the approved plan and covered by the permit.

3. No changes may be made to a plan for which a permit has been issued without review and written approval by the department.

4. The department shall be notified at least one week prior to the preconstruction meeting and at least one week prior to the commencement of land-disturbing activity.

5. The department shall conduct random inspections of the project to ensure compliance with the permit.

6. The department shall require inspections and reports from the state agency or federal entity responsible for compliance with the permit and to determine if the measures required in the permit provide effective stormwater management.

B. Compliance with the permit shall be subject to the following conditions:

1. Where inspection by the responsible state agency or federal entity reveals deficiencies in carrying out a permitted activity, the responsible state agency or federal entity shall ensure compliance with the issued permit, permit conditions, and plan specifications.

2. Where inspections by department personnel reveal deficiencies in carrying out the permit, the responsible state agency or federal entity shall be issued a notice to comply, with corrective actions specified and the deadline within which the work shall be performed.

3. Whenever the Commonwealth or any of its state agencies fail to comply within the time provided in a notice to comply, the director may petition the secretary of a given secretariat or an agency head for a given state agency for compliance. Where the petition does not achieve timely compliance, the director shall bring the matter to the Governor for resolution.

4. Where compliance for a state agency will require the appropriation of funds, the director shall cooperate with the appropriate agency head in seeking such an appropriation; where the director determines that an emergency exists, the director shall petition the Governor for funds from the Civil Contingency Fund or other appropriate source.

5. The department may also seek compliance through other means specified in the State Water Control Law.

Statutory Authority

§ 62.1-44.15:28 of the Code of Virginia.

Historical Notes

Derived from Virginia Register Volume 40, Issue 8, eff. July 1, 2024.

9VAC25-875-790. Maintenance and inspections.

A. Responsibility for the operation and maintenance of stormwater management facilities shall remain with the state agency or federal entity and shall pass to any successor or owner. If portions of the land are to be sold, legally binding arrangements shall be made to pass the basic responsibility to successors in title. These arrangements shall designate for each project the property owner, governmental agency, or other legally established entity to be permanently responsible for maintenance.

B. At a minimum, a stormwater management facility shall be inspected by the responsible state agency or federal entity on an annual basis and after any storm which causes the capacity of the facility principal spillway to be exceeded.

C. During construction of the stormwater management facilities, the department shall make inspections on a random basis.

D. The department shall require inspections and reports from the state agency or federal entity responsible for ensuring compliance with the permit and to determine if the measures required in the permit provide effective stormwater management.

E. Inspection reports shall be maintained as part of the land disturbance project file.

Statutory Authority

§ 62.1-44.15:28 of the Code of Virginia.

Historical Notes

Derived from Virginia Register Volume 40, Issue 8, eff. July 1, 2024.

9VAC25-875-800. Reporting on stormwater management.

State agencies shall report annually, on a schedule to be specified, to the department on the extent to which stormwater management programs have reduced nonpoint source pollution to the Commonwealth's waters and mitigated the effects of localized flooding. The report shall provide the following: data on the number and types of stormwater management facilities installed in the preceding year; the drainage area or watershed size served; the receiving stream or hydrologic unit; a summary of monitoring data, if any; and other data useful in determining the effectiveness of the programs and BMP technologies in current use.

Statutory Authority

§ 62.1-44.15:28 of the Code of Virginia.

Historical Notes

Derived from Virginia Register Volume 40, Issue 8, eff. July 1, 2024.

9VAC25-875-810. Technical criteria and requirements for state or federal projects.

A. Erosion and sediment control and stormwater management plans prepared for state projects shall comply with the technical criteria outlined in this part and any locality's VESCP or VESMP authority's technical requirements adopted pursuant to §§ 62.1-44.15:28 and 62.1-44.15:52 of the Code of Virginia.

B. The department may establish criteria for selecting either the site or a planning area on which to apply the water quality criteria.

Statutory Authority

§ 62.1-44.15:28 of the Code of Virginia.

Historical Notes

Derived from Virginia Register Volume 40, Issue 8, eff. July 1, 2024.