Outside In and Inside Out
by Doug Pushard
Harvested rainwater is used predominantly for irrigation and occasionally, with treatment, for drinking water. There are other uses, too, but most of the time, this pure and precious resource is allowed to just run down the street. We need to rethink how we use this limited resource by exploring ways to use and reuse outside water inside the house and inside water outside the house.
The typical home spends about 50 percent of its pure, costly drinking water on toilet flushing and clothes washing, yet these purposes do not require pure water.
Additionally, we all create nutrient-rich water that would be heavenly to most of our plants and yet we send this water to our local treatment plant to be treated and released to run out of our watershed. Based on City of Santa Fe data, this “waste” water accounts for approximately 35% of the water used in a normal household. This water is called greywater.
Greywater contains nutrients that our plants need and is produced daily in rather consistent quantities inside our homes. Rainwater is not so constant and in our arid climate must be stored to ensure a ready supply. Rainwater is relatively pure, with the exception of bacteria, and is also good for plants. With treatment either could be used inside for our toilets or clothes washing or with less treatment for our landscape.
Our current water use paradigm needs to change as we look toward a future with increasing water costs and less frequent but more intense storms. Updating our plumbing codes — as other cities have already done — to allow inexpensive and easy permitting of greywater use for subsurface irrigation would be a great place to begin. A longer-term step would be to require new homes to build in stub outs for greywater similar to Tucson’s ordinance. This makes it easier and less expensive for new homeowners to use this precious resource while saving taxpayer dollars by reducing water treatment costs. To really push this effort along, we could offer rebates and incentives to homeowners who want to do a retrofit to an existing home.
In addition to using our “inside” water outside the home, we can also use our “outside” water in. The harvesting of rainwater greatly reduces stormwater runoff, helps recharge our local aquifer and saves a local resource for a local beneficial use.
There is currently a permitting process in the city and county for these systems with rebates available in the city. However, these processes are targeted for irrigational use of rainwater and need to be updated to make it easy to use rainwater inside the building for non-potable use (i.e., toilet flushing and clothes washing).
This process, referred to in the plumbing world as bringing purple pipe inside the building, is permitted by national plumbing code but not our local or state codes. Consequently, these projects carry an added expense due to the time and effort required to work with local permitting and inspection agencies to obtain approval. A simple update to our plumbing and building codes would go a long way toward helping us use greywater and rainwater in a very different and beneficial matter.
Times are changing. Water is becoming increasingly precious and expensive. We need to begin thinking of new ways to conserve and reuse this life-giving resource. Easy, inexpensive steps can change the way we manage this limited resource and greatly increase our long-term water security.
Get involved. Push your local and state officials to modernize, award and incent conservation of our limited, local water supply.
Related Webpage: Water Conservation
Related Book: The New Create an Oasis with Greywater: Choosing, Building and Using Greywate Systems
Related Book: Green Plumbing Supplement (covers purple pipe plumbing code)
Related Article: Greywater Gone Wild
Design Services: Services