Wet Detention Basin Typical Maintenance Requirements
Reporting Requirements
An initial installation certification (as-built) stamped by a Professional Engineer (P.E.) registered in the state of Wisconsin shall be submitted to the City Engineer upon completion of construction. The as-built shall be of sufficient detail to show the system was properly constructed and is functioning as designed. It shall include a statement by the certifying P.E. along with a topographic survey and photograph(s).
An annual report shall be submitted via email to City Stormwater Management staff. The report shall include records of all inspections and maintenance performed for the year. Inspections shall be done every calendar year, with reports being submitted by June 1 of the following year.
Maintenance Provisions
Owner shall maintain records of installation, inspections, cleaning, replacement, and any other maintenance all in accordance with Chapter 37 of the Madison General Ordinances. Owner shall install and maintain the basin in accordance with plans approved by City Engineer and in accordance with WDNR Conservation Practice Standard #1001 West Detention Basin. Any alterations to approved system shall be approved by the City Engineer.
Visually inspect the detention basin, outfalls and outlet structure annually. The Owner shall maintain records of inspections, mowings, and survey data, all in accordance with Chapter 37 of the Madison General Ordinances.
No structures of any kind are permitted within the detention basin area, without prior written approval of the City Engineer.
A topographic survey of the detention basin shall be taken once every three (3) years. The survey shall be of sufficient detail so as to ensure maintenance of basin and outlet structure design and integrity of outfall structures. Survey data shall be sealed by a registered land surveyor and submitted to City Engineer for review.
Siltation in the basin, as identified by the topographic survey, shall be dredged and disposed offsite in accordance with NR 347. Dredging shall be as required by the City Engineer.
Vegetation Management
The detention basin shall be mowed a minimum of twice per year. Mowing shall maintain a minimum grass height of 6 to 8 inches. All undesirable vegetation and volunteer tree growth shall be removed, including those in close proximity to any outfall and the outlet structure.