Local water quality officials proposed on Tuesday fining San Diego $4.6 million for allegedly allowing private construction sites to pollute sensitive waterways, including the Los Peñasquitos Lagoon.

Over a period of nearly five years, city officials failed to conduct proper site inspections, prevent harmful sediment erosion and enforce the city’s water quality ordinances at multiple sites, according to the San Diego Regional Water Quality Control Board.

Erosion from construction sites can send sediment downstream to creeks and lagoons, where it can transport toxic pollutants, clog natural drainage systems and smother habitat, according to a six-page complaint issued by the board.

A city spokesman said officials were reviewing the complaint on Tuesday and examining ways to address the board’s concerns in a manner that would provide greater environmental benefits to communities in San Diego.


The city could pay the penalty, contest it or propose a settlement that may include a supplemental environmental project. The board has scheduled a hearing for Oct. 12.

The complaint blames the violations partly on poorly trained city inspectors, and calls the violations surprising because the regulations have been in place for more than 20 years.

“The water board expects the city’s commitment to water quality ordinances to be embraced more broadly by all city staff — not just the planners who wrote them,” said James Smith, the board’s assistant executive officer and leader of the prosecution team.

The complaint says the maximum fine for the violations, which also affected the Tijuana River Estuary in the South Bay, would have been $22.7 million. The $4.6 million proposed was described as the city’s “minimum liability.”


The alleged violations took place between October 2010 and May 2015.

The complaint says San Diego inspectors were either unable or unwilling to take the enforcement actions against construction sites that are spelled out in city ordinances.

It says city officials and the water board jointly crafted plans to address sediment problems affecting salt marsh habitat in the Los Penasquitos Lagoon, noting that the partnership prompted the board to take a flexible approach.

“The San Diego water board put a lot of resources into collaborative, outcome-focused efforts to protect and restore areas like Los Peñasquitos Lagoon and Tijuana River Estuary,” Smith said. “Enforcement like this is the result of a major deviation from the expectations we had for those partnerships.”


The complaint says an investigation by the board found city officials were allowing construction sites within the lagoon’s watershed to skirt erosion control requirements, leading to multiple instances of sediment pollution that could have easily been prevented.

San Diego Coastkeeper, a nonprofit group focused on local water quality, said it was disappointing to see such violations.

“It’s unfortunate that we still have municipalities failing to implement even the minimum measures necessary to achieve clean water when we know that stormwater pollution is one of the biggest threats to our water quality,” said Matt O’Malley, Coastkeeper’s legal and policy director.

O’Malley praised the board for its vigilance.


“We are pleased to see the San Diego Regional Water Quality Control Board working so diligently to protect the waters of San Diego,” he said.

The proposed fine is based on a formula of $10,000 per day, plus $10 for every gallon of pollutant discharge above 1,000 that does not get cleaned up. The formula also adds on 10 percent as a punitive deterrent.

Fine money goes into a statewide account for clean-up and abatement projects, but up to half could be set aside for local projects if the city and the board reach a settlement, a board spokeswoman said.