San Marcos, Texas
What is the Water Quality in San Marcos, Texas?
Compared to other US cities, San Marcos water quality ranks in the high-middle range for contamination excluding Lead.
Most of their 32 contaminants have cancer-causing attributes.
- Arsenic is at very high levels: 19x health guidelines.
- Haloacetic acids (HAA5) are at extremely high levels: 125x health guidelines.
- Haloacetic acids (HAA9) are at extremely high levels: 323x health guidelines.
- These are both byproducts of the chlorine treatment process most water supplies go through.
Let’s look closer at what’s in San Marcos water.
What’s in San Marcos water?
Here are the top 5 chemical compounds in your water and what health issues they can potentially cause:
- Arsenic – Potential effect: Cancer
- Bromodichloromethane – Potential effect: Cancer
- Chloroform – Potential effect: Cancer
- Haloacetic acids (HAA5 and HAA9) – Potential effect: Cancer
- Total trihalomethanes – Potential effect: Cancer
These are five of the 32 contaminants analyzed by the Environmental Working Group (ewg.org).
17 of these contaminants are rated as exceeding EWG Health Guidelines.
Does San Marcos have Lead contamination?
Yes, San Marcos has lead in its water. The most recent Lead samples collected in 2018 showed concentrations up to 2.1 parts per billion (ppb).
The legal limit for lead is 15 parts per billion. Being well-below this level is a good thing.
- Concentrations between 3.8 ppb and 15 ppb put a formula-fed baby at risk of elevated blood lead levels. Read more about the symptoms of Lead in water.
There is no safe level of lead for humans.
- The good news is that 99.99% of the lead can be removed.
See the What Can You Do? section below to learn how to filter out contaminants.
Where does San Marcos’s water come from?
San Marcos’s water comes from the Purgatory Creek – San Marcos River watershed.
All 5 water sources in the Purgatory Creek – San Marcos River watershed are in Good condition. These include:
- Four sections of the Upper San Marcos River
- Lower San Marcos River
Ideally, a water source would be rated in Good condition.
Whether a water source is in Impaired or Good condition refers to the quality of three uses:
- Aquatic Life
- Fish and Shellfish Consumption
- Recreation
Learn more from How’s My Waterway
See below for what you can do to improve San Marcos’s water.
What Can You Do?
Information about water quality in San Marcos can be surprising.
But there are things you can do in your home to clean up your water.
To Remove Lead and Other Contaminants In Your Home:
There is one solution that beats Brita, PUR, and expensive whole house systems.
- It costs less per gallon.
- Needs fewer filter changes.
- And it doesn’t make your water taste weird.
- Use Berkey filters with activated carbon to filter out at least 80% of contaminants in your drinking water.
- This includes Arsenic, Atrazine, Chloroform, and Haloacetic acids.
- Berkey filters can also remove up to 99.99% of Lead in San Marcos water.
- Brita can filter 16 contaminants and Lead depending on the filter.
- Note: We may receive a commission if you decide to purchase filters through links on this page.
- To filter out 29 of the 32 contaminants, consider a Reverse Osmosis water filtration system for your house.
- These are more expensive than pitchers to purchase, but can be more effective.
- They have the benefit of filtering out heavy hitters like:
- Aluminum
- Arsenic
- Atrazine – strong herbicide
- Barium
- Bromodichloromethane
- Bromoform
- Chloroform
- Cyanide
- Fluoride
- Hexavalent chromium
- Nitrate
- Nitrite
- Selenium
- Strontium
- Total trihalomethanes – byproduct of chlorination*
*Chlorination is an effective method of disinfecting/treating drinking water. You can then use a water filter to reduce the effects of chlorination byproducts to get the safest, cleanest water possible.
In Your Community:
Contact your local government officials and put pressure on them to invest in cleaner waterways and upgraded city water filtration and treatment.
Go to: http://www.sanmarcostx.gov/ to find contact information for your local officials.