GreenTown Los Altos

Stormwater RunOff

Believe it or not, the single largest source of pollution in the San Francisco Bay is…stormwater runoff.

Runoff is rain that falls onto hardscape such as the asphalt and concrete of driveways, walkways, and streets. These impervious surfaces in our urban environment prevent stormwater from naturally soaking into the ground.

What’s the problem?

Runoff flows through the system of curbs and gutters to storm drains that empty directly into our watershed. Along the way, beautiful rain transforms into a pollutant.

Stormwater runoff picks up oil, grease and metals from cars, chemicals that leech from asphalt, fertilizer, herbicides and insecticides from our landscape, and pet waste laden with bacteria and viruses. These pollutants pose health risks to humans, wildlife, and plants.

How you can help:  Minimize Hardscape. Maximize Greenscape.

Capturing rain where it falls helps to keep our waterways clean and healthy. Rain water is easily captured in rain gardens, vegetated swales, catch basins, dry creeks and other greenscapes. The water is purified as it gradually percolates through the soil and recharges our aquifers.

To learn more, watch this 3-minute video,  “Rain: Divert. Capture. We All Benefit:” plus “Capture Rain Where It Falls”, Part 1: The Problem of Stormwater Pollution and Part 2: The How To of Stormwater Capture, Get Ready for  
all created by GreenTown Water Team member Tami Mulcahy.

Be a part of the solution to stormwater pollution!