Water Wars
San Luis Obispo County is at war, at two wars actually. While the wars haven't been declared officially, they're hard to ignore. First, neighboring cities and developers fight over water rights, agriculture and municipalities point fingers over groundwater basin declines, air planes attack clouds with silver iodide, and expensive pipelines raise community ire. One war is for water. But, we consumers no sooner receive our precious water than we flush it away, let it run down the drain, or shunt it to gutters and sewers. The second war is against water. Over the past six months, one group of Paso Roble residents at Oak Creek Commons cohousing community has begun to confront this collective, cognitive dissonance by implementing several water-saving techniques in its landscape. Over time, these techniques will save water, bringing an end to both wars.
Capturing Rainwater, Hearts and Brains
As a background, Paso Robles is one of the dryest parts of the county, with an average rainfall of only 14 inches per year. The average residential water use in Paso Robles is around 115,000 gallons a year, all of which currently comes from wells. Paso will shift to depend on Lake Nacimiento water in the future, offsetting it's well-water use. Much of this hard-won water goes straight to the wastewater treatment plant. Some water, estimated by the EPA at about one third, goes to lawns and landscaping where much of it evaporates, runs off, or slowly descends back into the water-table. Water is scarce, and rates are set to double in the next four years.
Even with scarce, expensive water in a place like Paso Robles, it is possible to have green all year — and other colors too — if you like any of the many flowering drought resistant plants available to our excellent climate. Astonishingly, a 100' x 100' lot in Paso Robles receives an average of 70,000 gallons of rainfall per year! Most runs to the gutter — but some people have just begun tapping into this reserve by catching and storing rainwater in tanks, or cisterns, and using it to irrigate landscaping and gardens.
Oak Creek Commons residents got help when they installed their catchment system. In January of 2012 Cal Poly launched an innovative program to connect freshmen with the county community. Titled SUSTAIN, the program depends on relationships within a team of Cal Poly students, faculty, staff, and community members to facilitate real-world projects related to sustainability. The students, driven by purposeful projects, receive course credit for their projects, and the community reaps the benefits of their work. Cal Poly faculty and staff have even reported having a good time in this not-traditional educational system! (Visit the SUSTAIN website in references below.)
SLO SUSTAIN Students and Oak Creek Commons Community Members – Photo by Jim Cole
One of the first projects selected by a SUSTAIN student group involved installing a rainwater capture, or 'catchment' system on a carport at Oak Creak Commons in Paso Robles. With strong support from the community and weekly interactions, students designed, engineered, procured and installed the 450 gallon storage system. Besides negotiating typical 'hard', textbook engineering problems, students dealt with the more challenging yet fulfilling 'soft' social and financial intricacies of presenting the system to the community and raising funds.
While this catchment system was more complex and therefore costly than most (it includes a sand filtration system that can bring water quality to potable levels), simpler systems exist. With water rates nearly doubling over the next four years, it is conceivable that a basic system would actually pay back its cost in water savings in a few years! Reducing runoff through collection also saves on costly municipal infrastructure to build and maintain city drainages.
<— Four Hundred and Fifty Gallons of Rainwater Storage at Oak Creek Commons – Photo by Greg Ellis
Turf Your Turf
Rainwater catchment is just one way to end the water wars. Many water companies are waking up to the reality of water scarcity and thinking creatively. It doesn't take much thinking to understand that money is one primary human motivator. Paso Robles City has joined many cities in arid lands and now offers rebates of up to $500 to customers who convert water-hungry lawns to drought tolerant landscapes. Atascadero and Heritage Ranch CSD have begun similar programs. Residents at Oak Creek Commons (OCC) became aware of Paso's rebate program and jumped on board. OCC already has substantial areas of thriving, drought tolerant landscaping, but the nearly four acre development also has plenty of lawn. Some of the lawn, especially awkward, uneven sections located between sidewalks and homes, were already difficult to maintain, and made sense to convert.
Removing turf seems like a chore — who wants to dig out all that heavy sod!? Actually, it can be easier than that. Simply not watering a lawn for a few weeks in Paso kills it. Then, instead of removing it, the technique of 'sheet mulching' is employed to laziness' advantage. Sheet mulching involves laying cardboard (readily available from Wal Mart) over the lawn, then securing it under three inches of wood chips (for OCC, from trees recently trimmed on the property). Few grasses are tough enough to break through. The cardboard does allow water penetration and breaks down after a year. Wood chips continue to suppress weeds, and need to be reapplied every couple of years.
A Bee Enjoying Turf Conversion – Photo by Greg Ellis
OCC planted one gallon size plants purchased from local nurseries, including from One Cool Earth, keeping costs low. Small plants establish quickly when planted early in the growing season. The final planting was irrigated with high-efficiency drip emitters, using a fraction of the water consumed by the lawn. The plant list includes monkey flowers, penstemmon, artemesia, black and white sage, ceanothus, and other native and non-native, drought tolerant plants. In fact, once established, many of these plants don't need water during the six hot, dry months of our Mediterranean summer — for some natives, summer water even kills!
For more ideas about edible, drought tolerant landscapes, see last month's column about the Paso Robles Demo Garden.
More Water, Please
Rainwater capture and drought tolerant plantings are just two ways to bring an end the water wars happening in your toilet, wallet, the clouds, aquifers, and reservoirs. In next month's column, I'll discuss home greywater recycling and how to use the land itself to store water.
References
Cal Poly Sustain
SUSTAIN/OCC Rainwater Catchment System
Paso Robles Turf Conversion Incentive
Atascadero Mutual Water Company Turf Conservation and Water Conservation Incentives
Heritage Ranch Turf Conversion Incentive
SLO County DIY Landscape Design
Paso Robles Demo Garden
