First part of this series covers different design ideas for handling urban runoff on single family, multi-family and commercial developments. This is part 2.
Continuing from the Santa Monica Urban Runoff Management Program, this section covers their worksheet for a variety of construction activity or for voluntary participation.
Check with your local city to determine their stormwater treatment requirements on new or redeveloped construction. In some cases, changing 2,500 sq ft of pervious ground to 2,500 sq ft of impervious ground can trigger the need for stormwater treatment construction at the job site. The Federal Clean Water Act, enforced by the State Regional Water Boards mandates this requirement. In many cases, a regional “Municipal Regional Permit” will hold the design requirements for following through.
City of Santa Monica URMP
In the southern California city known for its nice beaches and celebrity homes, Santa Monica has an Urban Runoff Management Program aimed to reducing runoff from polluting Santa Monica Bay. In a city Ordinance Chapter 7.10 that was designed to reduce 0.75″ of rainfall leaving all “impermeable surfaces of all newly developed parcels within the City. … also specifies guidelines for existing properties to reduce the level of contaminants that are carried by urban runoff into the Bay.”
In their Urban Runoff Management Program brochure, they expand upon Best Management Practices for reducing urban runoff pollution. Information includes “increasing the percentage of permeable surfaces and landscaped areas by”:
- porous materials that will increase the amount of runoff that seeps into the ground, rather than being carried into storm drains
- natural drainage
- filtration pits
- swales, berms, green strip filters, gravel beds and french drains.