WAY FOUND TO STOP PORT ALGAE

June 11, 2000 12:00 am

The green algae that blights the water of the sports basin may be eliminated with the installation of four aerators.

This was the finding of a study made by the Army Corps of Engineers.

Russ Crabtree, port executive director, said the aerators are relatively inexpensive considering what they could mean to the port.

They are expected to cost about $3,200 each. He already is seeking grant funds.

The significance of the problem was evident Thursday as the algae collected around the new docks being installed in the sports basin.

The stuff also collects on the launching ramp. As the tide rises and falls, the algae is deposited on the ramp. The old ramp becomes slippery and dangerous to walk on.

The aerators would be put under the water, and would operate electrically.

Crabtree said he is happy the port waited for the engineers to complete the thorough study.

There is poor circulation of the water in the sports basin. It contributes to the problem, but is not the total cause. The study said that as part of the upgrade of Lower Harbor Road in 1978, outfall culverts were installed in the harbor. The culverts drain from roads and residential areas east of the port along Highway 101, the study says.

The culverts are believed to be possible point sources of nutrients that contribute to the problem.

Another contributing cause is untreated waste from boats entering the basin. This is despite the port offering services for pumping out the sewage.

Another potential source of nutrient input to the basin is from the use of detergents both in an area near the basin, and in the surrounding area, the study said. There is phosphate runoff from washing boats and vehicles outside, the study said.

The aeration system would mix the oxygen-rich water on the top with the oxygen-poor water on the bottom, the study said.

The sports basin measures 1,000 feet by 450 feet for the marina, and 320 feet by 560 feet for the turning area. This represents 629,200 square feet. The report said only the northern 600 feet will need the aeration.If the problem persists, the study said additional aeration units may be installed.