When it rains in California’s shopping malls and warehouses, water runs across parking lots carrying metal dust and chemicals from car tires and brake pads, oil and grease from engines, and germs from garbage.
Gunpowder washes away in storm water and pollutes streams, rivers and beaches.
Now environmental advocates are pushing state regulators to crack down on requiring stormwater permits — the best practices — for businesses that don’t account for their dirty runoff.
“The commercial properties are not currently regulated under any stormwater permit,” said Sean Bothwell, executive director of the California Coastkeeper Alliance. “Think of Costco, think of Amazon warehouses. Big places with big parking lots are what we want.”
Business groups say they already pay property taxes in L.A. County that include a special stormwater treatment tax, and that new rules like this don’t make sense.
But the California Coastkeeper Alliance and other nonprofits sent petitions to state water managers throughout this week demanding that they begin regulating commercial properties such as supermarkets, car dealerships and industrial parks.
A drone view of the East LA Sustainable Median Stormwater Capture Project in East Los Angeles.
(Robert Gauthier/Los Angeles Times)
The groups want the State Water Resources Control Board to establish a statewide regulation, or permit, for “commercial, industrial and institutional” facilities, including stadiums, shopping malls and private hospitals.
If the state does nothing, Bothwell said, “our waterways will not be safe to fish or swim in, especially Southern California beaches.”
That’s because a large portion of the waterways that pollute the water comes from these businesses. Bothwell said his group estimates, using methods developed by the Federal Environmental Protection Agency, that unregulated businesses are responsible for 30% to 60% of metals such as copper and zinc found in water, depending on location. At high levels, these are toxic to fish and other animals.
Many of Southern California’s canals and concrete channels are considered “impaired” by regulators because the levels of contaminants violate water quality standards.
The way California currently enforces the federal Clean Water Act, businesses are not responsible for reducing wastewater runoff, and the cost of cleanup efforts falls on cities and counties, Bothwell said.
Because large parking lots often contribute to the flow of polluted stromwater, environmental groups are urging state regulators to begin requiring permits.
(Robert Gauthier/Los Angeles Times)
Instead, the cities or counties where they are located are controlled. Researchers estimate that California cities and counties spend more than $700 million each year on stormwater capture and treatment.
California would be the first in the country to adopt such a standard or statewide permit. In addition to cities, the state already needs stormwater permits in construction sites, roads and certain industrial plants.
Business groups opposed the proposal. John Myers, a spokesman for the California Chamber of Commerce, noted that the effort to approve stormwater permits has been discussed for several years in LA County after environmental groups won a court ruling in their favor. “Choosing to use that effort as a template for various other states, without a careful analysis of the benefits and costs, would have a significant impact on the California economy,” he said.
The Los Angeles County Business Federation, or BizFed, raised similar concerns.
“Everyone wants clean waterways. However, this proposal is not ready for long-term implementation,” said Mike Lewis, BizFed’s water chairman.
As written, the proposal “hits existing property owners with retrofit costs while at the same time ignoring the stormwater taxes they’ve been paying faithfully for years,” Lewis said in an email. “This looks like no environmental policy and is like a fine. There are better, fairer ways to treat stormwater.”
If there was a national scale for commercial enterprises, many would have to build retention ponds or swales to filter out contaminants before the water seeps underground. Or they can pay an annual fee, helping to fund local stormwater projects that cities need.
The money raised from the companies, Bothwell said, will be used to build wetlands, catchment parks and other green spaces near parking lots — which help clean water instead of letting it run into storm drains.
At the same time, cities in Southern California are investing in stormwater capture projects and groundwater recharge as needed. less dependent on water it is imported from Northern California and the Colorado River.
Unless the state takes action, wastewater will continue to flow from commercial parking lots into canals, adding to the “toxic soup” in Southern California’s waters, said Bruce Reznik, executive director of Los Angeles Waterkeeper.
The California Coastkeeper Alliance and a coalition of local water conservation groups have sent petitions to regional boards in the Inland Empire, San Diego, Bay Area, Central Coast, North Coast and Sacramento Valley.
They asked for a provision of the Clean Water Act which authorizes states to seek additional permits on a case-by-case basis.
LA Waterkeeper and other environmental groups successfully used a similar provision to convince the EPA by 2024 to require business permits near the Dominguez station and the Los Cerritos station in LA County. State regulators are preparing to issue those permits.
Water district boards have received new petitions and will process them, said Ailene Voisin, spokeswoman for the department.
In 2022, Gov. Gavin Newsom opposed legislation that would have required floodwater permits for most businesses across the country. In 2025, a similar bill faced opposition and died in the Legislature.
