There are always two sides of a coin. Southern California has been gripped by powerful and fierce storms this year that have wrecked havoc and caused extensive damage in some communities. Images of uprooted trees, flooded streets and homes, overflowing storm drains, and terrifying mudslides have dominated television and newspaper coverage. Drought warnings, mandatory water conservation and rationing may be distant memories to many who reside in the coastal plains from Ventura County to San Diego, but we should not rest easy. While we’ve experienced record-breaking levels of rainfall and snowpack in 2011, much of that water can’t be physically captured. And that situation brings me to the other side of the coin. That surplus water, angrily raging through concrete river channels and dumping out into the Pacific Ocean, presents a significant and unique opportunity for Southern California to improve its water supplies and rise to new standards of environmental stewardship. The challenge: Capture that stormwater now, bank it and save it for a future dry day.

Californians have demonstrated a strong commitment to the environmental mantra, “reduce, reuse, recycle.” That same principle needs to be applied aggressively to making more efficient use of our finite water supplies. In this arid state, every drop counts.

In Southern California, we rely on three primary sources for our water supplies. Water is imported from the Colorado River Aqueduct and the State Water Project, which funnels Sierra snowpack water through the Sacramento-San Joaquin Delta. Approximately half of our region’s water comes from imported sources. However, these supplies are becoming increasingly less

reliable. Groundwater basins or aquifers, replenished by rainwater that slowly percolates underground, also provide water for our thirsty residents, farms and businesses. In addition, cities and water districts throughout Southern California are recycling wastewater and storing it underground for later use. Stormwater is another important component of our overall water supply portfolio, and is rapidly gaining recognition and appeal.

Capturing and reusing stormwater is viable, cost effective and environmentally preferable. Approximately 500,000 acre-feet of stormwater is currently captured and recharged into Southern California groundwater basins in an average year. That’s enough water to supply three million people for a year, or satisfy the water supply needs of San Diego, Anaheim, Riverside, Santa Ana and Long Beach combined. Here’s the good news — we can do even better. Throughout the region, we could capture up to one million acre-feet of stormwater in an average year, significantly enhancing local supplies and reducing reliance on imported sources.

Public water agencies have been successfully constructing stormwater projects that recharge aquifers or help fill surface reservoirs. In Los Angeles County, the Sun Valley Park Project is designed to solve local flooding while retaining all stormwater runoff from the surrounding areas that drains into the park. The project, which has garnered national recognition and awards, will increase water conservation, enhance residential recreational opportunities, and reduce stormwater pollution. Given it’s been a very wet year, Los Angeles County has captured more than 230,000 acre-feet of stormwater this storm season to date. In the Inland Empire, water agencies in San Bernardino County have collaborated to construct a new stormwater project at Seven Oaks Dam that will recharge the Bunker Hill and adjacent groundwater basins with previously unobtainable runoff from the San Bernardino Mountains. And, the Orange County Water District has developed a partnership with the U.S. Army Corps of Engineers to store stormwater behind Prado Dam for percolation along the Santa Ana River, helping to ensure an adequate and cost-effective water supply for the growing population in that county.

In our coastal communities, many municipalities have built stormwater projects that help clean stormwater before harmful pollutants, swept along with the runoff, reach the ocean. The

City of Hermosa Beach was just recognized by the U.S. Environmental Protection Agency for its innovative and environmentally friendly project that captures excess water from storm drains, cleans it by filtering through sand, and then returns it to the groundwater table.

Many of these projects have been funded with voter-approved statewide bonds, including Proposition 50 and Proposition 84. Voters may be asked to consider another water bond in 2012, which would help our public water agencies make further investments in additional projects.

Residents can also play a critical role in this effort by installing rain barrels and roof capture systems, replacing concrete and asphalt with more porous materials and paving stones, and implementing landscape designs that better enable the excess stormwater to percolate into the ground, rather than runoff into drains and streets.

Our organization is spearheading a regional collaboration to encourage and support stormwater projects, policies, legislation and funding opportunities, uniting for the first time ever the six counties in the Southern California coastal plain – Ventura, Los Angeles, Riverside, San Bernardino, Orange and San Diego – on this issue.

It’s difficult to watch the often devastating impacts of these storms but important to remember the two sides of the coin. These storms provide us an essential resource. California suffers from recurring and painful drought cycles, increasing vulnerabilities and constraints on our major water delivery systems, and crumbling infrastructure that was built decades ago for a much smaller population. These threats to our water supply reliability jeopardize our economy, jobs, environmental resources and treasured quality of life. Capturing more stormwater in Southern California is a clear priority and an important long-term investment in our future.

Richard W. Atwater serves as the Executive Director of the Southern California Water Committee and has spent more than 35 years working in water resources and wastewater management.