Rainwater Harvesting in Taos
by Doug Pushard
is critical to life and especially so in Northern New Mexico.
In the Taos area both commercial and private home builders are proactively adopting rain catchment systems, reusing greywater and xeriscaping.
Taos has an average annual rainfall of 13 inches, so a house with 2,000 square feet of roof area can catch almost 15,000 gallons of rainwater a year. This is more than adequate for most households (See Tank Calculator)
A lot of the water harvesting system in the area catch water and supply all the water needs of the home, both for drinking and irrigation. The roofs are mostly smooth surfaces that drain into gutters. The downspouts send the water through a particle filter to a large cistern for storage. The cisterns used in the Taos area vary in size and materials, pre-fab or site-built, and can typically be installed for about a $1.50 - $2.50 per gallon. Price will also vary depending on remoteness and conditions of the roads to the site.
“Because of the high cost of drilling and the remoteness of the some of the locations in the area harvesting rain just makes sense,” according to Charlee Myers, owner of Mountain & Mesa Construction in Tres Piedras, New Mexico. “We have seen rainwater systems become more and more mainstream as out here everyone seems to know someone with an installed system,” he concludes.
A lot of homeowners in Taos do not have ready access to city water so they have to choose between drilling a well or harvesting rainwater. With wells costing between $10,000 to $30,000 and rainwater systems costing between $4,000 - $7,500 a lot of homeowners outside the city are opting to harvest the rain.
In most households, up to 60% of household effluent is greywater (from sinks and showers/tubs) which can be reused for landscape irrigation. The reused water benefits plants with increased nutrients and phosphates. Greywater from the house collects in a holding tank, and may optionally pass first through an indoor wetland planter, creating a beautiful indoor garden. Irrigation water for outdoor gardens is pumped directly from the holding tank. Overflow will typically go to a leach field or in some cases to a septic system.
By local building code, irrigation with greywater has to be used below ground level which is ideal for water-efficient drip irrigation. In the semi-arid Taos climate, landscaping gardens with plants that thrive on less water, such as native grasses and wildflowers, makes great use of the greywater.
A septic system installed in the Taos area runs about $2,000 or they can choose composting toilets for around $1,000 each and a smaller separate greywater holding tank for about $1,000. The latter approach is a more efficient use of water in an area that sometimes experiences weeks without rain during the summer and is fairly common in and around Taos.
Given the independent streak of those choosing to build in Taos it is not surprising to see quite a few opting for both rainwater harvesting and greywater systems - saving both money and helping the environment.