Heal the Bay: Model Land Use Ordinance on Runoff

The Urban Runoff Problem 

Urban runoff is more than the rainwater that flows into our storm drain system; it is also the water we use every day to irrigate our plants and wash our cars. During the dry season, runoff amounts to millions of gallons each day entering the Santa Monica bay. During a rainstorm, the volume is measured in billions of gallons daily. 

The pressure to change how we deal with this water is coming from many sources. The EPA is making sweeping changes in urban runoff permits, directing all major cities in the country to change the system un­der which they permit discharge into the storm drain system. 

The city of Los Angeles is be­ginning a two-year multifaceted edu­cation program on controlling urban runoff. And environmental groups (especially Heal the Bay) have spent years pushing for education and re­form of the urban runoff problem. But to understand the issue, it is important to first understand the mag­nitude of pollution carried by the runoff in our urban areas.

Now that Los Angeles’ Hyperion sewage treatment plant is literally cleaning up its act, urban runoff has become the largest source of pollut­ants to our near-shore waters — the zone in which we swim, surf and fish. This pollution is called non-point source pollution because its exact sources cannot be pinpointed — they are everywhere. 

In our long local stretches be­tween rains, all the herbicides and pesticides we put on our lawns, the decaying vegetation we sweep into the streets, the oil we carelessly dump after servicing our cars, and the droppings from all the dogs we walk everyday find their way into our storm drains, waiting for the next rain to flush it into the ocean.

When it does rain, the runoff washes into this mixture all the smog that has settled onto our rooftops, the soot from our sidewalks, and the oil and grease deposited on every park­ing lot, street, and freeway in the entire Los Angeles watershed. All of it is picked up by the rainwater, channeled into our storm drain system, and flushed into the bay. None of it is treated. 

A Land Use Ordinance 

Land use ordinances represent part of the solution by dealing with the runoff that each development produces. Heal the Bay has worked with the City of Santa Monica in creating the first such statute. The ordinance looks at existing developments, sites under construction or remodeling, and proposed new developments. 

The idea is to reduce both the amount of runoff leaving each site and the toxics within that runoff. In Santa Monica the goal is a twenty percent reduction in volume. 

The Santa Monica ordinance in­cludes two types of requirements: Good Housekeeping and Design En­hancement. Good Housekeeping is a group of common-sense guidelines designed for the occupants of a devel­opment rather than those who design them: don’t store hazardous materi­als where they can get rained on and leak into the storm drain system; don’t leave leaking machinery where oil or other fluids can drip into the system: don’t put landscape debris into a storm drain. 

What Developers Must Do 

The second major section of the ordinance deals with developers and the steps they must take to achieve a 20% reduction in runoff. New de­velopments in Santa Monica must submit an urban runoff mitigation plan to the City’s Department of General Services. The plan must show how, by using Best Management Practices (BMP’s), the reduction will be achieved. A sampling of BMP’s:

• Increase landscaping, to allow more runoff to seep into the site. (Landscaping acts as a natural filter, removing pollutants from water traveling to the storm drain system.)

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• Construct driveways and walkways of porous materials that will allow water to seep back into the ground.

• Fully utilize low-lying areas that may become natural detention basins for rainwater.

• Collect and store rainwater in cisterns, using it to water your in­creased landscaping later.

• Modify sloping areas to direct runoff into landscaping.

• Design curbs that allow water to flow into landscaping rather than acting as a dike to keep water out.

• Keep parking lots clean, and provide oil and water separators or clarifiers for the runoff flowing off of parking lots. As much as possible, keep water off of parking lots in the first place.

Which of these or other BMP’s will be used by any given developer is purely a matter of personal choice, so long as the plan submitted meets or exceeds the 20% reduction requirement. The Santa Monica ordinance provides that each plan will be evalu­ated on its own merits, and requires a City response to plans within two weeks. 

Other sections of Santa Monica’s ordinance provide for waivers when compliance cannot be met and outline specific BMP’s for construction sites. A final section sets up an annual evaluation to review the ordinance permitting procedure and to revise the process if necessary. 

Looking Ahead

The City of  Santa Monica has passed a resolution to create an or­dinance: final passage of the ordi­nance is expected during August. Santa Monica would become the first city in Southern California to estab­lish a Land Use Ordinance for urban runoff, but it will certainly not be the last. 

The EPA has issued a new policy on National Pollution Discharge Elimination System (NPDES) per­mits, obligating cities to implement BMPs for the control of stormwater runoff. Within Los Angeles county, Santa Monica is one of nineteen cities (including the City of Los Angeles) signed on as co-permittees of the new NPDES permit. All are expected to adopt some form of Land Use Ordinance. 

Other cities beyond the county of Los Angeles will be encouraged to follow suit, as well. Each city adopt­ing an ordinance will certainly tailor their BMP list to their specific needs. Because Malibu (which is also developing an ordinance) is more sparsely populated than Santa Monica, their runoff concerns, such as erosion, differ greatly.

As more cities adopt Land Use Ordinances, landscape designs that are sensitive to urban runoff will become the norm, and will represent giant steps toward cleaning up our storm water as it runs its course to the bay.