New Rainwater Harvesting Class

The Texas AgriLife Extension Service is holding its third "Rainwater Harvesting for Landscape Professionals" course in Houston on Friday, November 4 from 8:30 am to 4:00 pm. This course is open to the public and will provide participants the information that they need to get started in rainwater harvesting. It is geared towards those looking to use rainwater harvesting for irrigation purposes, but there is also useful information provided for those using it for indoor use. Please see https://agriliferegister.tamu.edu/events/details.cfm?id=903 for more information.

In-Home Use in Texas

As of September 1 of this year, it is now legal for Texas residents connected to municipal water to use rainwater for indoor potable purposes. Prior to the 1st, residents with a city-water connection could use rainwater for anything except drinking. With rainwater harvesting gaining popularity in all parts of the state and water supplies decreasing, politicians were pressured into updating the law in HB 3372. The main delay in this new law and emphasis made is the prevention of backflow from a rainwater system into a city water systems. Municipalities are concerned that poorly maintained RWH systems could leak contaminated water into city mains. With HB 3372, backflow prevention devices are required to address this concern.

Youth Education

With the current drought situation leaving most of Texas exceptionally dry, now is a opportune time to teach our state's youth of water conservation. The Texas AgriLife Extension Service is currently taking part in a project aimed at educating youth about water conservation. In addition, they focus on educating teachers and Master Gardeners to teach youth about water-related issues. This helps to multiple the impact that Extension has on the state's water literacy. The topics that the Extension Service focuses on are watersheds, vegetation's importance in water conservation, and rainwater harvesting.

Current Research

Because rainwater harvesting has only recently become mainstream, the research available is limited. Many times, Extension employees are unable to answer a client's question because there is no or limited data to support an accurate answer. Part of our mission in educating people is doing the research so that those questions can be answered. In the coming weeks, we will discuss the various research that we have completed or are currently doing.

In the picture above, we have 12 rain barrel-sized containers that each hold 55 gallons of water. There are three sets of four barrels. Each set has four different colors and is under a different shading: full sun, partial shade and full shade. We have inserted a temperature probe into each barrel to measure water temperature over time.

High temperatures in rainwater harvesting tanks may compromise water quality or effect plant growth. From this experiment we hope to determine what particular color of water tank and what amount of shading helps keep the temperature moderated and cooler during the hot Texas summers.

Water Security

In the summer of 2009, a U.S. District Court told Atlanta that they have until 2012 to resolve water issues with neighbors Florida and Alabama or the city would have their supply of water cut off from Lake Lanier. The lake supplies 3 million Atlanta residents with water, but it is being done illegally. A federally-funded, Corps of Engineers reservoir, Lake Lanier was originally built (in 1956) for hydroelectricity and flood control. As Atlanta's population grew, so did its water demand. It was not made for public water supply. After the drought of 07-09, Alabama and Florida challenged Georgia in court since both states rely on water flowing downstream from the lake. Now Georgia is passing a bill that includes several water conservation policies, such as prohibiting daytime (10-4) outdoor watering and using more efficient devices. If practices such as these are put into place, millions of gallons could be saved, which could lessen the tension between neighboring states.

If problems are not resolved, officials will be rushing to find a new water source for millions of Atlanta residents. Rainwater harvesting on homes and apartments could supply people with water without the massive infrastructure needed to pipe in water from a remote source. It puts the responsibility and ownership of water in the user's hands. This ensures the user has water regardless of what fate may become of Lake Lanier.

Rainwater Harvesting in Haiti

Even before the earthquake in Haiti last month, water and sanitation conditions were extremely poor. According to the World Health Organization, only 11% of of Haiti's population had drinking water piped into their dwellings in 2006. 42% of the population had unimproved drinking water sources, which includes unprotected wells or springs, surface water, or tanker trucks.

Needless to say, the earthquake destroyed much of infrastructure used to transport clean water. Aid organizations have been working tirelessly in distributing water to Haiti's people. UNICEF itself is distributing nearly 700,000 gallons of water every day.

During the rebuilding process, rainwater harvesting should be considered as a long term water source. Compared to complex underground infrastructure, it is relatively inexpensive and would be a job that locals could participate in. It could be installed quickly to lessen the burden on aid organizations. And education is key: 40% of Haiti's population are below the age of 14. Teaching them the basics of sanitation and water treatment would prevent many of the water-born diseases that kill countless people every year.

Rainwater Harvesting on Campus

Texas A&M University recently opened the Mitchell Physics Building in College Station. This building, like all new construction on campus, is LEED certified. LEED, which stands for Leadership in Energy and Environmental Design, is a national rating scale that focuses on sustainable building practices. The Mitchell Building was built at the silver standard of LEED certification, and it includes rainwater harvesting.

Rainwater and air conditioning condensate are captured from the rooftop and sent to an underground cistern (diagram below). This water is then used to irrigate landscaping in the front of the building (picture upper right) and the roof-top garden (picture upper left). This is the University's first roof-top garden.