Responding to concerns over last weekends massive fish die-off at Atascadero Lake, city officials say it wouldnt be cost-effective to add water to the drought-plagued local attraction, as some residents have suggested.
Such a move would cost a minimum of $500,000 over 48 days, according to the city.
Right now, pumping water in a drought where it would be very costly and most of it would evaporate wouldnt be the most cost-effective thing we could do, Mayor Tom OMalley said Wednesday.
Hundreds of dead fish floated to the lakes surface this past weekend, prompting a widespread cleanup. In hot weather, algae blooms grow and decrease the waters oxygen levels. That process, paired with shallow water warmed by summer temperatures in the 90s and 100s, caused the fish to die.
The scene wasnt new. Hundreds of fish died in 2001, and about 30 more died in 2008.
The city doesnt know exactly how many fish died Friday through Sunday. Members of the cleanup crew didnt count as they plucked the dead carp and perch from the murky waters banks and hauled them away in trucks, officials said.
Atascadero Lake was a mess (last) weekend, and I dont think you can just brush it off. Its an embarrassment to the city, lakeside resident Nancy Hair said at Tuesdays City Council meeting. She wants water added to the man-made lake off Highway 41, on the citys west side.
Before Hair spoke, City Manager Rachelle Rickard presented the statistics and costs associated with such a move.
The lake, which can hold up to 68 million gallons of water over 30 acres at capacity, is currently about 30 percent full, Rickard said. The maximum depth at capacity is 13 feet, but the lakebed is currently just 4 1/2 feet below the surface at its deepest point. The southern half of the lake, meanwhile, is no more than 1 1/2 to 2 feet deep today, she said.
The conditions are the worst the city has seen in decades.
It would cost the city $8,600 at 1.4 million gallons per day to buy water from the areas private utility, the Atascadero Mutual Water Co. (plus additional money to dechlorinate it), to pump it into the lake bed.
The effort would add about 3 inches of water per day, Rickard said, slowing as the water level rises and evaporates at a rate of 135,000 gallons per day.
Hair also suggested that the water company pump in water without charging the city. John Neil, general manager of the utility who attended the council meeting on another topic, said his board of directors would have to approve such a measure but that its not something the board is considering because of pumping and treatment costs.
Meanwhile, while the five-member City Council didnt discuss whether to support adding water since the topic wasnt officially on the agenda, OMalley said its not something the city is considering, either.
It really wouldnt be that effective at this point. This would be a good time to dredge what we can and clean up the lake, he said.
Officials already have applied for a state permit to dredge the dead plant material and silt that builds up over the years from the lakes bottom, hoping to improve its health when rain returns.
Dredging would also deepen (the lake). That would be the best we could do, and then let Mother Nature fill it up, OMalley said.
The city has also been monitoring the waters oxygen levels and, earlier this summer, installed three floating fountains designed to produce more oxygen in the water. Last weekend, three additional pumps were brought in to aerate the water.