Section NR 151.249 - Swale treatment performance standard(1) REQUIREMENT. Except as provided in sub. (2), transportation facilities that use swales for runoff conveyance and pollutant removal are exempt from the requirements of ss. NR 151.242 to 151.244, if the swales are designed to do all of the following or to the maximum extent practicable: (a) Swales shall be vegetated. However, where appropriate, non-vegetative measures may be employed to prevent erosion or provide for runoff treatment, such as rock riprap stabilization or check dams. Note: It is preferred that tall and dense vegetation be maintained within the swale due to its greater effectiveness at enhancing runoff pollutant removal.
(b) Swales shall comply with the department technical standard 1005, "Vegetated Infiltration Swale", dated May, 2007, except as otherwise authorized in writing by the department. Note: In accordance with subch. V, the Department of Natural Resources has updated technical standard 1005, "Vegetated Swale," dated December 2017, which is the current authorized technical standard. The technical standard is available from the department at dnr.wi.gov.
(2) OTHER REQUIREMENTS. (a) Notwithstanding sub. (1), the department may, consistent with water quality standards, require that other requirements, in addition to swale treatment, be met on a transportation facility with an average daily traffic rate greater than 2,500 and where the initial surface water of the state that the runoff directly enters is any of the following: 1. An outstanding resource water.2. An exceptional resource water.3. Waters listed in section 303 (d) of the federal clean water act that are identified as impaired in whole or in part, due to nonpoint source impacts.4. Waters where targeted performance standards are developed pursuant to s. NR 151.004.(b) The transportation facility authority shall contact the department's regional storm water staff or the department's liaison to the department of transportation to determine if additional BMPs beyond a water quality swale are needed under this subsection.Wis. Admin. Code Department of Natural Resources NR 151.249
CR 09-112: cr. Register December 2010 No. 660, eff. 1-1-11.Amended by, correction in (1) (b) (Note) made under s. 13.92(4) (b) 7, Stats., Register November 2018 No. 755, eff. 12/1/2018