The time for expanding the city's deteriorating sewage treatment plant has "clearly arrived," but it will take at least three years before any substantial construction can be completed, according to a draft report by an engineering consultant.
The report, prepared by the Long Beach engineering firm of Moffat & Nichol, also said the existing plant with modifications and a higher maintenance budget could accept higher flows and organic loads and still meet state effluent treatment requirements until expansion is completed.
City officials, however, are still seeking funding for the expansion project. City Manager John Longley and Mayor Gilbert Saldana are in Washington, D.C., this week along with a lobbyist trying to get the city included on a funding list in the federal Clean Water Act currently before a U.S. Senate subcommittee.
If Avalon cannot get the nearly $2 million it needs from the federal government, the city will have to look to the state, Longley said. If that fails, local taxes on residents and visitors might have to be raised. Residents already pay about $170 annually per household to keep the plant running.
Andrew Gram, the project engineer who prepared the report, said the sewage flow reaching the treatment plant has been increasing in recent years at a rate faster than the growth of the permanent population.
From 1980 to 1984, the population grew from 2,022 to about 2,200, while the average daily sewage flow during the same period increased from 374,000 gallons to nearly 500,000 gallons. The plant, completed in 1976 to accommodate five years' growth, has a 500,000- gallon capacity.
But during the summer, when the daily population swells to nearly 6,000, the daily sewage flow has reached 800,000 gallons. The report said that with the addition of 250 condominiums in Hamilton Cove, the city could experience daily average flows of more than 900,000 gallons and peak days of nearly 1.2 million gallons by the year 2000.
sh Untreated Sewage
The city is already in trouble with the state Water Quality Control Board for discharging effluent not meeting minimum treatment standard. The city has until April 15 to submit a compliance plan. The Moffat & Nichol report is part of that plan.
The City Council took a quick stab at solving the city's sewer problems earlier this month by asking the water quality board for permission to discontinue treating its sewage before dumping it into the ocean. That was after news reports that the board had allowed the dumping of toxic wastes into the ocean about 20 miles north of Santa Catalina Island's west end as late as the mid-1970s.
However, a water quality board official said this week that the agency will not grant the city's request.
The city's problems began in 1983 when one of the plant's clarifiers--which treat the raw sewage--broke down at a time of high flows. Raw sewage seeped out onto the beach and streets during the July Fourth and Labor Day weekends.
Record Flow Levels
Last year, the sewage flow reached record levels, and for three months the effluent was below minimum treatment standards because the flow was too fast to be properly treated.
Avalon sewage is unusual because of its high salt content from sea water used for flushing. The report said salt intensifies corrosion of metal fixtures and equipment, aggravates problems with the buildup of hydrogen sulfide (which emits a rotten-egg smell), and reduces the efficiency of oxygen flow in the aeration process of the treatment.
In addition, the report said engineers had to inspect manholes to make a map of the sewer system lines, some of which were found to be sluggish and operating below capacity. The report said more manholes needed to be built and existing ones needed to be cleaned of debris.
Gram said the current plant's flow and load can be increased by decreasing the amount of sludge mixed with the sewage during treatment and increasing the amount of oxygen. In addition, a pumping station at Pebbly Beach should operate at variable speeds to provide a continuous flow, rather than on-off as it now runs, he said.
The city has applied to the federal Environmental Protection Agency for a waiver that would allow it to eliminate secondary treatment of sewage. Eliminating the second treatment would quickly increase the plant's capacity from 500,000 to 800,000 gallons a day. A decision on the waiver is expected this summer.
Whether or not the waiver is granted, Gram said, the city should proceed in obtaining financing for new construction because costs of an expanded primary or a secondary treatment plant with daily flow capacities of 1.2 million gallons are each about $2 million.
Both projects would require new equipment, but Gram said the primary treatment plant would be less costly in the long run because of savings in power, labor and maintenance costs.