Storm Water – Not a Waste But a Valuable Resource of Water (1)

Vasona park and the adjacent Los Gatos Trail is a favorite place for many locals who live in the South Bay of the San Francisco Bay area.  The long trail along the picturesque creek and reservoir provides a perfect place for people to walk, run, or just to relax and enjoy.  In the last couple weeks, though, as like so many other places in Northern California, the heavy storms flooded part of the trail.  The creek turned muddy yellow, roaring downstream at a much faster pace than normal.

Stormwater flooded Los Gatos trail

The creek literally has become a river.  It did not just flow out of the creek banks; in this particular area it flooded the whole place, including the trail, until it was blocked by the higher bank, off which the trail’s parking spaces sit.  The flow was so powerful that it knocked down a pole of the trail’s fence.

Flood at Los Gatos Creek

Fence Pole

Nowhere was the storms’ effect more apparent than at the dam of Vasona Reservoir. Usually the dam gates were closed, the creek tranquil; now the gates are wide open, with a huge volume of muddy storm water tumbling down, making a spectacular fall.

dam before storm

dam after storm

dam after storm

Storm Water Benefit  – Recharge Ground Water

While the heavy storm water did flood part of the trail, the water itself is not a waste; on the contrary, it is a very valuable resource.

One of Los Gatos Creek’s major functions is to recharge ground water. According to the park’s official website:

“Surface water runoff from the watershed that drains into Los Gatos Creek is captured by Lexington Reservoir in the Santa Cruz Mountains. That water is then used to recharge, or refill, the valley’s groundwater basin. Reservoir water is released and carried to recharge ponds via the creek. Water held in the ponds seeps or “percolates” through the earth’s layers until it reaches underground aquifers. This percolation process helps clean the water before it reaches the underground storage basin.

All along Los Gatos Creek you will see groundwater recharge in action. Water released from Lexington Reservoir flows to Vasona Lake where a system of gates at the dam releases water downstream to the percolation ponds at Los Gatos Creek County Park and Budd, Camden, McGlincey, Oka Lane, Page and Sunnyoaks ponds. Ultimately, the creek joins the Guadalupe River and flows northward to San Francisco Bay.”

Here is one of the percolation ponds at the creek:

percolation pond

Ground water is an important source of water for California.  In the last several decades, overpumping has seriously depleted a lot of the ground water, sinking the land across the state.  The historical drought in the last 5 years made the depletion even worse, exacerbating an already severe situation . It is critically important to recharge the ground water, and the storm water this season is badly needed.

Storm Water Benefit  – Water for Trees

Walking along the creek one can see quite some trees toppled in the storm.

tree toppled in a storm

While some trees may simply just be brought down by the force of the wind and flow, for  some other trees, it was the drought – they were so weakened by the time of the storm.

Since 2010, more than 102 million of trees have died in the California forest stressed by drought and infected by beetles, estimated the U.S. Forest Service.   As trees are so vital for the environment,  this is not something anyone would like to see.  The storm water can help quench the thirst of the trees, helping them stay healthy and live much longer.

Storm Water Benefit  – A Richer Habitat for Birds

A happy surprise one would discover walking along the creek was birds rarely seen before.   While some birds, e.g., Canada Geese, Great Egret, and Mallard Ducks  can be seen all the time, a much bigger variety showed up after the storms:

birds after storms

birdafterstorm
Double-crested Cormorant

birdsafterstorm

Like a lot of wetlands in the state, Los Gatos creek was a bird’s paradise a long long time ago, but human activities took away most of the habitat.  The drought just made it much worse for the birds.  Now, with the abundance of water and food brought by the storms, more birds came back.  It is clear that water is essential for the health of wetland’s ecosystem, and storm water plays a big role in it.

Net, from Los Gatos creek, one can see storm water is such a valuable resource.  It can recharge ground water, de-stress the trees, and help provide a habitat for birds.  It is not a waste that should be flown out to the ocean as soon as possible; rather, it is something that should be captured, stored and reused, so we can achieve a much higher efficiency for the water we get.

 

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