By Steve D Gilder
Water Conservation
As we move forward into the 21st century two things are going to remain true: the population of the City of Austin and surrounding area is going to increase, the amount of water available will not. The Colorado River's flow will not expand to cover the increased demand and the aquifers beneath us will not be sustainable unless rainfall patterns change and the extended drought ends. The damming of the Colorado to form the Highland Lakes was in response to the extended drought of 1950-57, however there are no plans in the works for any additional reservoirs.
"Currently, about 95 percent of Texas is in either a severe or exceptional drought status and the... year {2011} has been the worst one-year drought in the state's history," says John Nielsen-Gammon, State Climatologist at A&M University. He also puts forward the possibility the drought could extend into the future as far as 2020.
Austin's water supply challenges are becoming more evident as demonstrated by recent record heat and drought conditions. The emergence of the "Sometimes Islands" in Lake Travis are a reminder of the pressure our water supply system can suddenly come under when our average annual rainfall amounts drop considerably. (Austin gets about 34 inches of annual rainfall.) The good news is that Austin has secured long term water rights and contractual rights for roughly twice as much water as is currently being used - to water in the river that runs through the city. Austin's adoption of its aggressive conservation goals comes from dedication to water conservation as a value and with long term sustainability in mind, and without the immediate financial or water supply pressures faced by places like California and western desert cities who have to pipe water from distant sources reliant upon historic rainfall amounts that have diminished over recent years.
It should also be noted that strong conservation efforts by Austin do not necessarily result in more water remaining in the Colorado River and the Highland Lakes. Under the current LCRA Water Management Plan, any water savings realized by the City of Austin is water available to be sold by LCRA to other customers. The biggest water user along the Colorado River is not the City of Austin, but downstream rice farmers who regularly use more than three times as much water annually as does the City of Austin (including water used by Austin Energy to generate power). In fact, during the drought, while Austin implemented Stage 2 restrictions, including limiting irrigation to one day per week, rice farmers made no cutbacks and actually exceeded their projected use in the Water Management Plan. The City of Austin used a total of around 139,000 acre feet of water, compared to the 450,000 used by rice farmers downstream.
Water Conservation: A Local History
The City of Austin's first water use management ordinance was enacted in 1983. It allowed for the implementation of water restrictions in response to infrastructure constraints, but more as a crisis management tool than an actual water conservation strategy.
Since that time demand has increased as the population soared.
- 1990 - 466,000
- 2000 - 656,000
- 2010 - 790,000
Source Ryan Robinson, City Demographer, Dept of Planning, City Of Austin, March 2011
Between 1995 and 2009 water use per year has gone from 39,585 to 53,328 (in millions of gallons) Because of this changing demographic Austin has focused more on water conservation as a means to extend the available infrastructure capacity as well as reducing the city's carbon footprint. To enhance ongoing conservation efforts, Austin's City Council passed a resolution on August 24, 2006 that set a goal of reducing peak day water use by one percent per year for ten years. As part of that resolution, the City Council established a Water Conservation Task Force (WCTF) and charged it with drafting a policy document consisting of strategies and implementation plans for new water conservation initiatives that would allow Austin to meet its goal for reducing peak day use.
As part of the resulting actions in the 2007 charge, City Council established the Citizens Water Conservation Implementation Task Force (CWCITF), whose members included environmental advocates, development advocates, irrigators, and others with expertise and interest in water conservation, and tasked them with monitoring water conservation efforts in Austin. On August 6, 2009, the City Council adopted a resolution that directed the CWCITF to work with City staff and applicable Boards & Commissions to produce a report recommending additional water conservation measures to reduce water use beyond the 2007 WCTF recommendations. After this report was complete, on May 13, 2010 City Council charged the City Manager with evaluating the CWCITF's recommendations and developing an action plan that would reduce average water use in Austin to 140 gallons per capita, per day (GPCD) or lower by 2020.
In July 2010, Austin Water introduced a pilot program to encourage residential customers to replace turfgrass with native plants or non irrigated areas. Even at a modest incentive amount, this program is not expected to generate enough water savings to meet cost benefit benchmarks; however, it will generate interest in xeriscaping and opportunities for customer education that have non quantifiable benefits, including reductions in chemical use and runoff.
Austin Water will continue to provide free irrigation system checkups to customers, and will increase focus on high use customers through targeted marketing and outreach. Austin Water is developing online tools to help customers with lower water use perform basic system checkups and maintenance so that staff time can be focused on the highest water users. Customers required to submit regular irrigation evaluations would not be eligible for this free service once the mandatory requirement is implemented; efforts would focus on small commercial and high residential users. This measure does not meet cost benefit benchmarks for average day savings due to the seasonality of irrigation; however, it was determined to be a successful peak day management strategy in the 2007 WCTF report.
The Future
So, as we move forward what can we expect to see? The lowest point of winter water usage to the highest summer usage the increase is nearly 50%, and we know most of that is for outdoor watering, the lawn guzzling down most of that. So we can all expect The City of Austin to concentrate its conservation efforts in that area.
The only way to curb excessive water use is to reduce lawn areas and to practice Xeriscaping. So look to see incentives for homeowners to take that route.
The American Water Works Association (AWWA) estimates that homes with in-ground irrigation systems use 35% more water than homes without such systems. And households that use automatic timers for their irrigation systems use 47% more water than households with in-ground systems operating their systems manually. Staff at the Austin Water Utility have observed water loss of 20% to 50% from inefficient irrigation system design.
Drip System irrigation is targeted toward the root systems of plants and is covered by a good depth of mulch (3-4" minimum) and is by definition the most efficient irrigation system concept by far. It saves a good percentage of water from evaporation alone.
Future incentive schemes might resemble that already practiced in Pflugerville which offers a flexible landscape rebate program, where the city refunds half the cost of trees, shrubs, mulch, and certain types of turfgrasses on its approved plant list up to $500 per customer.
http://www.cityofpflugerville.com/index.aspx?nid=1244
Rainwater harvesting is becoming more and more popular as a conservation method and Austin Water streamlined its rainwater programs and increased incentive amounts in July 2010. This is intended to highlight the program for a brief time to increase awareness of rainwater harvesting. Incentives are expected to continue through 2012, at which time the program will be reevaluated. Follow the link to find out more.
http://www.ci.austin.tx.us/water/conservation/rebates.htm
Water Conservation is an essential part of the Xeriscape movement especially in Central Texas.
If you would like to learn more about the concepts of Xeriscaping, visit our website at http://xeriscapeaustin.com
There you will find lots of information on all facets of Xeriscaping, including rainwater harvesting: http://www.xeriscapeaustin.com/rainwater-harvesting/
Article Source: Water Conservation in Central Texas
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