Does a sediment basin need to control or limit peak stormwater discharge?

Watershed disturbance, whether during construction or post-construction phases, can increase the peak flow of runoff water for all levels of storms before leaving the project site. Local community, county or city stormwater or development regulations commonly limit the peak flows from project sites to the peak flows that existed prior to site disturbance (i.e., pre-construction) conditions for specified level(s) of storm events. For example, a local government stormwater regulation may specify that the peak flow from a project site shall not exceed the pre-construction peak flow for one or more storm frequency events such as the 2-, 5-, 10-, 25-, 50-, and/or 100-year return period storm event(s). While there is no direct Tennessee statute governing stormwater control requirements, settled case law and requirements established through TDEC’s administration of EPA’s Phase II, MS4 rule for stormwater runoff quality and quantity management, recognize the need for restraint and control. ...  more