How Can You Help With Water Conservation?
Lake Mead
It is no secret the southwestern United States is experiencing extreme drought conditions. The unsettling photos of water levels in Lake Mead and Lake Powell are just some of the more prominent examples of the widespread issue facing residents. Water supply availability for the approximately 60 million residents in the drought-stricken area is the obvious issue, but maybe just as important is that the west relies to a significant degree on hydropower for our electricity.
That hydropower generation is being threatened, as water levels drop to historically-low levels, with Lake Mead and Lake Powell getting dangerously close to their “minimum power pool”. This is a lake level below which hydropower can’t be generated. Lake Mead generates approximately 4,000 gigawatt-hours per year and Lake Powell produces approximately 5,000 gigawatt-hours per year (which is changing as water levels continue to decline); the average home in the United States uses 11-12 megawatt-hours per year, that’s about 750,000 homes that rely on power from just these two lakes. And Lakes Mead and Powell are not the only lakes in the southwestern U.S. that are facing these water and power issues.
Lake Powell
So, how can everyone help with mitigating the drought conditions? Most people are aware of water-saving devices for homes, such as low-flow showerheads, toilets, dishwashers, and washing machines. These measures are all highly encouraged and are effective in reducing in-house water use, but are you aware of how much annual water use is related to landscaping irrigation? Figure 1 shows a typical water demand curve for a municipality. Typically, water use for the months of November through February represents the average in-house water use. Therefore, everything above this average use (dashed line in Figure 1) is attributed to outdoor landscaping water use. Outdoor water use for landscaping can represent 60 to 70 percent of all annual water use!
Figure 1: Example Water Demand Curve
How can you help with water conservation to help mitigate the drought conditions that are likely going to limit water availability in the future if no action is taken? There are a number of ways to reduce water usage. These ways include:
Look around your yard to see if there are grassed areas that are being irrigated that serve no useful purpose, e.g., for your children to play on. If so, consider removing this turf and replace with one of the options described below.
Replace turf with drought tolerant plants or trees, e.g., species native to Colorado.
Consider rocking areas that provide no use in your yard.
Check your sprinkler heads and make sure you have efficient heads and that they don’t leak.
Install an automatic rain shutoff sensor.
Install a moisture sensor in your lawn to indicate when the grass needs moisture instead of having it set on a standard schedule.
Install drip irrigation for plants and trees.
The southwestern U.S. is the home to approximately 60 million people. At an average of 3 persons per home, that is 20 million homes. While water use varies from place to place, a typical annual water use per home averages between 0.3 to 0.5 acre-feet per year (“ac-ft/yr”). If each home could save 0.1 ac-ft/yr, that is 2,000,000 ac-ft/yr of water saved! Even half of that is 1 million ac-ft/yr per year. That’s a pretty big savings if everyone pitches in!
LWS has extensive experience assisting water suppliers with developing not only water efficient practices but we have also helped develop indirect water reuse systems. If you have any questions related to water conservation or water reuse please contact us (303-350-4090) or send an email.
Bruce Lytle, P.E., bruce@lytlewater.com
Chris Fehn, P.E., P.G., chris@lytlewater.com
Ben Bader, ben@lytlewater.com
Anna Elgqvist, E.I., anna@lytlewater.com
Dan Rowe, P.E., dan@lytlewater.com
