Water, water everywhere, but what is right for me? With water we do have lots of choices and not all are created equal. You are probably wondering what I am talking about. What choices, what water?
Of course there is city water that most of us utilize abundantly. But we also have rainwater, greywater and blackwater. All of these are potential sources of water that could be used to drive our net water use to zero or better; helping us to become a net producer of water.
Each one of these waters has different characteristics that make it well suited for a primary, secondary and tertiary use. Each type of water has different upfront costs and varies on impact of net water use. For example, city water has chlorine added to help keep it disinfected one route to our homes from the distribution plant. This same chemical may create healthy water for us, but over the long-term is not healthy for plants. It creates salt build-up in the soil that rainwater and fertilizers help offset.
So city water is a good primary source of potable water, but should be secondary or tertiary when it comes to landscape water use. See Fig. 1 for a summary of the characteristics of each source of water.
Of course, the advantage of city water is that it is plumbed to almost every house and it is relatively cheap. The disadvantage is that it is not right for all uses. Looking at the sources of water without considering costs would result in a much different water use pattern. For example, if all homes were plumbed for water storage and had water filtration systems, we would use the best water for the right use to minimize or eliminate our water footprint. See Fig. 2 for “Current Water Use Patterns.”
Looking at our water use from this perspective rather than our water use pattern might look something like the following. See Fig.3 for “Future Water Use Patterns.”
Blackwater, greywater and rainwater all require some form of onsite treatment to be able to use as depicted in the chart above. These technologies exist today and are very feasible.
If implemented in this fashion our water footprint would drop significantly. One local Santa Fe area resident that has mirrored this water use pattern is using just 15 gallons per day per person (GPCD). Compare this to our citywide average of 90 gallons! This does not require a radical take-no-showers lifestyle change; it only requires a change of how we think about water. Instead of thinking tap water is free and all other water is water, think of all water as precious and lifegiving.
Aside from the obvious benefits of saving water and extending our water supplies well into the 22nd century, our plants and soils would be healthier, producing more fruit, vegetables, flowers and shade at a much lower water cost than today. Our need to be taxed to secure future water sources and build new filtration plants would be all but eliminated for the foreseeable future.
We have vast amounts of wasted water today. We must view this water not as waste, but as precious and irreplaceable. With this mindset we will begin to change our behavior and assure our water security for decades to come.
Doug Pushard is an EPA WaterSense partner with Certification in Irrigation Auditing. He is an active member of the City of Santa Fe Water Conservation Committee and was a co-founder of the Water Efficiency Rating Score (WERS®). Pushard designs and consults on rainwater and water-reuse systems locally and around the country. firstname.lastname@example.org