Irrigation is by far the largest use of water on the property. Winter use is about 6 CCF per month (600 cubic feet per month). In the absence of more efficient irrigation, usage is 30 CCF per month in mid-summer.
Shower GreyWater Reuse
Shower water is about half of the typical house water usage. This soapy slightly dirty water, about 40 gallons per person per day, (120 gallons per day or 4CCF per month) is useful for irrigation. Reclaimed greywater can only be used for subsurface irrigation. Greywater is captured with extra plumbing, and then filtered prior to distribution.
Winter Rain Water Storage
Winter produces an excess of water, an average of 12 inches of rain in winter. The soil is clay bearing and does not drain fast runoff from the roof, patio and other hard surfaces. The estimated rain collectable from the hard surfaces is 4000 cubic feet (40 CCF) or 30,000 gallons.
We aim to store 15,000 gallons of winter rainwater in underground cistern tanks for summer subsurface irrigation. Excess rain will go into french drains and rain pools by trees. The amount of water stored will be equivalent to a avings of a month of non-optimized summer irrigation.
More Efficient Irrigation
The garden irrigation system will be upgraded to include subsurface drip for distributing stored rainwater and greywater. Actual savings to be determined. We are also examining using a well to further augment subsurface irrigation.