City of Avalon Background Image

Clean Water overview

Avalon Bay sometimes experiences water quality issues that result in the bay being 'Posted' (recommended for no contact). This is because periodic testing conducted by the County of Los Angeles determines that our bay's water quality does not pass certain state standards.

These standards were established by a state law known as AB 411. AB 411 mandates that all waters along California's coast must meet certain minimum standards. In order to ensure that these standards are met, coastal waters are tested weekly during the period of April through October. In Los Angeles County, the county Health Department has the responsibility to test in Avalon Bay.

Why does the bay sometimes fail the weekly testing process? Unfortunately there is not an easy answer to that question. Over the past 24 years many theories have been advanced, all of which have some validity. However, the reasons fall into four categories:

Discharges from holding tanks - boats moored in Avalon Bay
In 1988, the City adopted a dye tab program to combat this concern. When recreational boats enter Avalon Harbor to spend the night, a harbor patrolman enters the boat and places a dye tablet in the boat's holding tank system. After that if the boat discharges it's holding tank into the harbor, either on purpose or accidentally, the water around the boat will be colored by the dye. If this happens, the boater is ejected from the harbor and is banned from re entry for a period of one year.

Bird droppings in the bay
There is scientific evidence that at least some of the high readings are caused by bird droppings. Like most waterfronts, our bay attracts it's share of pigeons and seagulls. Over the years the city has taken steps to make the bay less hospitable to our feathered friends. This has primarily consisted of stringing monofilament line in certain areas, installing devices that discourage ‘bird parking’ along the rooftops of our public buildings and ensuring that trash cans in the public areas are covered to discourage birds from congregating.

During the summer of 2012, the city is going to embark on a pilot project to alter the way we clean our docks. The public dingy docks and floats sometimes become the final resting place of bird droppings. Because this is a health and safety issue, particularly on floats where the cross channel boats land, our harbor workers wash the floats down early in the morning. We are currently conducting a pilot study to alter our wash down procedures to determine if they affect water quality.

Our sewer collection system
The City of Avalon, like many communities that are over 100 years old, had an aging sewer system that resulted in some waste leaching into the ground beneath the city. Since the city resides in a valley and sits on shallow bedrock, ultimately any such leaching goes ' downhill' and ends up at the lowest elevations, near sea level. Once there the tidal movements, combined with the city's shallow water table result in some of this waste entering Avalon Bay.

Since the late 1990s the city has engaged in various sewer upgrades to improve the integrity of the collection system. A complete list of these improvements can be found by clicking here.

Improvement Measures

In 2011 the city hired an outside engineering firm to take video pictures of the city’s entire collection system, analyze which portions needed repairs or rehabilitation and supervise the construction of needed improvements. Basically these improvements fall into three categories:

1. Slip lining - a process to line older sewer mains with a resin like substance which seals any leaks that might have been created over time by movement, ground shifting, etc. many sections of the city’s collection system have been slip lined in recent years.

2. Rehabilitation - this is the process of actually opening up the street, removing a portion of a block's sewer mains and replacing them with completely new lines. In 2012, the city replaced many of the sewer lines on the west side of town.

3. Manhole renovation - A manhole basically exists to allow access to one portion of the collection system. Older manholes are constructed of bricks; newer manholes are built form stacked concrete rings. Manholes also can leak and the solution is to line them in a similar fashion as slip longs described above. Over the past several years the city has lined almost all of it’s manholes.

Bay Chemistry

The bay itself contains naturally occurring organisms which create bacteria. These bacteria can cause some readings. Other areas of the state, most notably Mission Bay in San Diego, have experienced this phenomenon.

In addition, although the city has taken almost every step to line, repair or rehabilitate it's sewer collection system, there is still likely to be some legacy bacteria in the ground, and shallow ground water that ultimately finds its way to the bay, particularly as a result of rain water entering the ground and percolating out to the bay and as a result of tidal exchange.

The city is now exploring seeking approval to inject a neutralizing agent into the ground to fight, and neutralize this legacy bacterium.