National Groundwater Awareness Week

Threats to Groundwater

There is no doubt that groundwater is an important and valuable resource, as it provides a large percentage of water supplies in Texas.

Most of Texas’ major and minor aquifers provide safe and sufficient water for all uses. Existing groundwater quality in Texas varies among the major and minor aquifers.

Natural Contamination

In a small percentage of wells, contaminates such as nitrate, sulfate, arsenic, radionuclides, perchlorate and total dissolved solids have exceeded federal standards.

There is some debate as to whether all occurrences of these constituents are naturally occurring or the result of man-made activities.

The Texas A&M AgriLife Extension Service (AgriLife Extension) has developed a number of Drinking-Water Problems Fact Sheets which discuss the sources, health-effects, where problems are known to exist, what can be done by the well owner, and different water treatment methods that can be used by the private well owner.

All of these Fact Sheets can be found at the AgriLife Extension online bookstore (https://agrilifebookstore.org/):

• Publications L-5450 and L-5450S (“Solving Water Quality Problems in the Home” in English and Spanish, respectively) and E-176 (“What’s In My Water?”) are a good introduction to this subject.
• Additional publications of interest include Arsenic (L-5467 and L-5467S), Perchlorate (L-5468 and L-5468S), Nitrate (B-6184 and B-6184S), Radionuclides (B-6192 and B-6192S), MTBE (L- 5502), and Benzene (L-5513).

Contamination from Human Activities

The Texas Groundwater Protection Committee’s Joint Groundwater Monitoring and Contamination Report (“Joint Report”) includes the documented cases of groundwater contamination resulting from activities regulated by Texas state agencies (https://www.tceq.texas.gov/publications/sfr/056).

For each case, the report includes the site location, the type of contamination, and the status of the remediation effort. The most commonly reported contaminants are from leaking petroleum storage tank facilities containing gasoline, diesel, and other petroleum products.

These sites are often located in heavily populated areas of the state such as Houston, Dallas, Fort Worth, San Antonio, and El Paso. Of the 3,307 cases of documented groundwater contamination reported in 2018, 34 percent were related to the underground storage of petroleum products.

In addition, the volume of water used, stormwater contamination, and the poor maintenance of septic systems are also threats to groundwater that have been recognized by the Texas Groundwater Protection Committee.

Use

Simply put, we use a lot of groundwater. Although many think of it as an abundant resource, it is limited. There are many uses of groundwater including municipal and rural use for drinking water and sewage systems, agricultural use for irrigation and livestock, and many industrial uses.

Overuse of groundwater can obviously result in quantity issues, but overuse can also cause problems with water quality because it can mine the resource, resulting in lower quality water being produced.

Although programs exist to help protect our sources of drinking water, including groundwater, we the users are the most important actors in protecting these resources.

Here are some things you can do to help conserve your groundwater:

• Run full loads of dishes and laundry.
• Check for leaky faucets and have them fixed.
• Keep a pitcher of drinking water in the refrigerator.
• Purchase water-efficient appliances.
• Utilize drought-tolerant landscaping.
• Don’t over water plants and lawns.

Stormwater

Rainfall in urban areas can threaten groundwater by carrying contaminants into the groundwater as recharge to the aquifer.

There are three main types of stormwater pollution: litter, such as cigarette butts, cans, paper or plastic bags; chemical pollution, such as detergents, oil or fertilizers; and ‘natural’ pollution, such as leaves, garden clippings or animal droppings.

This ends up discharging into waterways as sediment, sludge, and solids or recharging aquifers.

The most effective way to reduce contamination is to prevent pollution from entering the stormwater system.

Here are some examples of what you can do to prevent groundwater contamination from stormwater:

• Dispose of chemicals properly.
• Take used motor oil to a recycling center.
• Limit the amount of fertilizer used on plants.
• Decrease or eliminate fertilizer and pesticide use.
• Wash your car at a car wash where water is collected for treatment before discharge.
• Never dump oil or other hazardous materials down the storm drain or on pavement that will eventually lead to the storm drain.
• Clean up automotive spills.

Many cities have household hazardous waste drop-offs. Does yours?

Onsite Wastewater Treatment Systems

Sewage systems dispose of waste from homes and businesses — often referred to as Septic Systems. Proper maintenance, construction, and use can protect groundwater resources.

However, improper use and poor maintenance can lead to contamination of groundwater supplies from bacteria, viruses and other pollutants.

Here are some management ideas to improve your septic system performance:

• Install a low-flow toilet. Well-designed units give a complete flush with 1.28 gallons per flush. Caution: displacing water with bricks or water bottles in old toilet tanks often gives less than a total flush and dissolving bricks can cause leaking problems.
• Install low-flow showerheads, handheld showers with pause control, and temperature balance valve controls.
• Shut off water while shaving and brushing teeth (saves up to 5 gallons per minute).
• Do not use a garbage disposal or dispose of vegetables, meat, fat, oil, coffee grounds, and other undigested food products in the septic system (use composting or garbage service.)
• Reduce the use of drain cleaners by minimizing the amount of grease and food particles that go down the drain.
• Wash only full loads. Adjust load level settings for small loads.
• Reroute the water softener and iron filter recharge water outside the septic system. It does not need to be treated.
• There is no quick fix or substitute for proper operation and regular maintenance. Do not use starters, feeders, cleaners, and other additives. Many of these additives suggest they work via “enzyme” or “bacterial” action. But there are millions of bacteria and plenty of food for them entering the system in normal sewage. If the bacterial activity level is low, figure out what is killing them (for example, household cleaners) and correct it. High levels of activity will return after the correction.