For The Answer
Primetime NewspapersBy Calvin R. Finch, PhD, SAWS
We have had over a month without rain and many days with highs in the mid nineties to low 100’s. As you might expect we are using a lot of water on our landscapes. For a while the aquifer was falling at .5 to .7 feet per day. At .5 feet/day and without any heavy rains that would mean that the aquifer would reach 650 feet MSL in about 40 days or at the end of August. At 650 feet MSL, San Antonio Drought Restrictions go into effect. In 2000, the last time drought restrictions were declared for any significant period (6 months), water use fell by about 20% the first month and about 14% over the entire period. The main restriction in San Antonio is the requirement that all lawn watering take place on one day per week based on address. If the restrictions proceed to Stage II, you can still water one day per week, but the number of hours that you can water on your day is reduced by four hours. Even when we are not in drought restrictions, San Antonio, and many other area cities restrict watering to the period 8:00 p.m. to 10:00 a.m. Watering in the middle of the day is not efficient because of evaporation.
In really severe droughts when the aquifer falls to below 630 feet, lawn sprinkling is limited to once every two weeks. Once every two weeks sounds severe, but even St. Augustine in the sun will stay alive with water every two weeks. Zoysia, buffalo, and Bermuda grass can go dormant and do not need any summer watering; they green up when the rains return.
We could have drought restrictions if the drought continues, but here are my reasons why I do not think it will happen in 2005.
· The agricultural irrigators that also use aquifer water have finished irrigating corn, the largest crop in terms of acreage and water use. There is still cotton to irrigate, but the volume of use is less. The end of corn irrigation probably was a main cause of the reduction in aquifer drop farm .5 - .7 feet per day down to .2 - .4 feet per day.
· Several thousand Edwards Aquifer area homeowners are following the Seasonal Irrigation Program (SIP) recommendations. Individuals can obtain the recommendations based on grass type and amount of sun on the lawn from the SAWS website, saws.org. It is even more convenient to sign up on the website to receive a weekly e-mail or phone message telling you how much water your lawn needs to keep it green without wasting water. There is also a SIP hotline at (210) 281-1478. Just call on your watering day to receive the recommendation. SIP saves the average homeowner about 20% of their normal lawn water use.
· The Conservation Enforcement Officers are on the job. Most of us call them the Water Police. They patrol San Antonio alerting businesses and homeowners when they are violating the watering guidelines (8:00 p.m. – 10:00 a.m., and no water leaving the yard). The Water Police are regular certified police officers so they also write misdemeanor citations for individuals that do not respond to the educational approach.
· It is very unusual for us to go through July and August without a good rain. All that is required to slow the aquifer drop is one or two good rains in that period. The weather prognosticators forecast a wet autumn so we just have to survive this summer.
· SAWS has 1.5 billion gallons of water stored in the Aquifer Storage Facility (ASR) in South Bexar County. That water will be pumped back into our system to reduce the need for pumping water directly from the Edwards Aquifer. Most golf courses and other large lawn areas are now using reuse water. SAWS wastewater is treated to make it clean and used to irrigate large landscapes.
We have plenty of water in San Antonio for our landscapes, but we do not want to waste any. It is my prediction that despite the high temperatures and lack of rain in 2005, we will escape drought restrictions.
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