Va. Code Ann. § 62.1-44.15:52
A. The Board shall develop a program and adopt regulations in accordance with the Administrative Process Act (§ 2.2-4000 et seq.) for the effective control of soil erosion, sediment deposition, and nonagricultural runoff that shall be met in any control program to prevent the unreasonable degradation of properties, stream channels, waters, and other natural resources. Stream restoration and relocation projects that incorporate natural channel design concepts are not man-made channels and shall be exempt from any flow rate capacity and velocity requirements for natural or man-made channels as defined in any regulations promulgated pursuant to this section or § 62.1-44.15:54 or 62.1-44.15:65. 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 man-made channels shall satisfy the flow rate capacity and velocity requirements for natural or man-made channels if the practices are designed to (i) detain the water volume equal to the first one-half inch of runoff multiplied by the impervious surface of the land development project 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 it 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 it was in a good forested condition divided by the runoff volume from the site in its proposed condition, and shall be exempt from any flow rate capacity and velocity requirement for natural or man-made channels as defined in regulations promulgated pursuant to § 62.1-44.15:54 or 62.1-44.15:65. For plans approved on and after July 1, 2014, the flow rate capacity and velocity requirements of this subsection shall be satisfied by compliance with water quantity requirements in the Virginia Erosion and Stormwater Management Act (§ 62.1-44.15:24 et seq.) and attendant regulations unless such land-disturbing activities (a) are in accordance with the grandfathering or time limits on applicability of approved design criteria provisions of the Virginia Erosion and Stormwater Management Program (VESMP) Regulations, in which case the flow rate capacity and velocity requirements of this subsection shall apply, or (b) are exempt pursuant to subdivision G 2 of § 62.1-44.15:34.
The regulations shall:
1973, c. 486, § 21-89.4; 1988, cc. 732, 891, § 10.1-561; 1993, c. 925; 2004, c. 431; 2005, c. 107; 2006, c. 21; 2012, cc. 785, 819; 2013, cc. 756, 793; 2015, c. 497; 2016, cc. 66, 68, 758.