Kate Williams walks around Lake Vasona 5 days a week. She takes in the view of the hills, surrounding foliage and lake. She became alarmed when she noticed dead fish floating beneath the bridge of her walking path.
”There are 15 to 20 fairly large sized, bloated, dead fish to be seen everyday,” Williams told Patch in an email.
While the sight of dead fish was unsettling, Williams was also concerned about the big picture, “A lot of animals depend on this waterway now that the Perc Ponds (percolation ponds to replenish the water table) have been allowed to go dry during this drought.”
Michelle Leicester, Unit Biologist for the California Dept. of Fish and Wildlife, says that the fish kill and drought are intertwined. She told Patch that low water flow produces two death sentences. The first is lack of oxygen, instant death, while the second is algae blooms.
She describes the blue-green algae blooms this year as the worst she’s ever seen. The blooms further deplete the supply of oxygen, sometimes taking the oxygen level down to zero. Furthermore, the algae causes liver damage in vertabrates, which eventually kills the fish.
The impact of the multi-year drought on fish goes beyond Silicon Valley’s border. Earlier this summer the California Natural Resources Agency raised the alarm about salmon stuck in streams that have slowed to a trickle. The fish “become easy prey trapped in small pools or die as the pools disappear. In other cases fish are weakened by poor water quality and low oxygen levels, making them less likely to survive to adults.”
According to Leicester, several Bay Area counties have lost all steelhead trout in 2013 and 2014. There wasn’t enough water in streams this year for steelhead to spawn. Any juveniles that survived from last year were killed when the streams slowed to a dribble or went dry.
Back at Lake Vasona, Williams worries about the immediate ramifications of the dead fish, “I see people fishing here and wonder if the fish are safe to eat?”
“No,” says Leicester. But the reason has
nothing to do with the fish kill. “All of the waterways in Los Gatos or
the Guadalupe River system have naturally ocurring mercury.” So the fish from Lake Vasona are never safe to eat.
Kill Your Lawn
Leicester has a simple message for all Californians, “Kill your lawn. The single biggest thing anybody can do to lessen their water footprint is to kill their lawn.” She says it isn’t just the water use that’s an issue, but pesticides, herbicides and fertilizers used to keep lawns lush and green. Strong water flows are needed to flush those chemicals from creeks and streams that receive runoff, and we simply aren’t seeing any natural water flow.
So what should people do who love their lawns? Leicester is blunt, “Move to Florida.”