Virginia Law

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.