One way to gauge the health of Galveston Bay is to assess the levels of life-sustaining nutrients and oxygen. Too many nutrients can cause algae blooms that deplete oxygen and harm aquatic life. However, plant life which is an important link of the bay’s food web requires nutrients. Water quality grades in the 2023 Report Card reflect conditions in the Bay and its watersheds in 2022. The levels of nutrients and dissolved oxygen found in the 2022 samples were overall at acceptable levels for supporting diverse and healthy aquatic life. The water quality issues that do arise are primarily due to runoff and wastewater from human activity.
Water Quality Summary
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What We Can do
- Follow these tips for organic lawn care on the upper Texas coast. Going organic can save you money and keeps toxic chemicals out of the environment and out of our waterways.
- Slow your runoff by reducing paved areas and installing rain barrels.
- Pick up after your pets and properly dispose of pet waste.
Nitrogen
Nitrogen is important to the Bay because it stimulates plant growth. But too much nitrogen can cause an algae bloom, which can deplete oxygen in the water and kill aquatic life. In 2022, nine percent of nitrogen concentrations in regional waterways were above water quality standards in samples collected from Galveston Bay, and 13 percent of samples collected from the rivers and bayous surrounding Galveston Bay.
Many watersheds in the Galveston Bay region receive an A grade, and most watersheds did have enough samples for a grade, unlike 2020 and 2021.
Nitrogen in Water
Nitrogen levels have been steadily improving in recent years. How did Galveston Bay’s levels fare this year?
What We Can do
Keep Excess Nitrogen Out of Our Waterways
- Follow fertilizer directions carefully and don’t overfertilize. Going organic is a great way to reduce the amount of fertilizer you use!
- Leave as much of your property unpaved as possible.
- Plant a rain garden that collects rainwater and allows it to soak into the soil.
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Galveston Bay Nitrogen
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Rivers and Bayous Nitrogen
Be frugal with water and fertilizer use – Don’t fertilize your local waterway
Phosphorus
Phosphorus, like nitrogen, is a nutrient that stimulates plant growth. But too many nutrients can lead to algae blooms, which can deplete oxygen in the water and kill aquatic life. In 2022, zero phosphorus concentrations were above state screening levels in samples collected from Galveston Bay, and 28 percent of samples collected from the rivers and bayous surrounding the Bay.
In 2022, the watersheds in the Galveston Bay region received A’s, B’s, C’s, D’s and one F. Addicks Reservoir, Brays Bayou, Buffalo Bayou, Greens Bayou, Sims Bayou, and Spring Creek all received D’s; while Barker Reservoir received an F grade.
Phosphorus in Water
Did you know phosphorus from detergents and plant fertilizer can harm aquatic habitats around the Bay? Find out how you can help.
What We Can do
Keep Excess Phosphorus Out of Our Waterways
- Use phosphate-free or phosphate-reduced laundry, dish, and car-washing soaps.
- Incorporate landscaping techniques that require less fertilizer, like growing a garden with native plants.
- Control erosion. Phosphorus attaches to soil particles, making erosion a contributor to phosphorus pollution.
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Galveston Bay Phosphorus
C
Rivers and Bayous Phosphorus
Water sparingly and apply the correct amount of fertilizer to reduce lawn care cost
Dissolved Oxygen
Just as people need oxygen to breathe, adequate oxygen levels in water are required to support aquatic life in Galveston Bay and area bayous. Hypoxia (low-oxygen) and anoxia (no-oxygen) zones are common after large algae blooms in water that is warm, still, and has poor clarity. Benthic (bottom-dwelling) organisms can’t escape or survive in hypoxic conditions. In 2022, dissolved oxygen no samples collected in Galveston Bay had dissolved oxygen levels below the screening levels set for the protection of aquatic life. Levels were below state screening levels in only 13 percent of samples collected from the rivers and bayous surrounding the Bay. As a result, all of Galveston Bay continues to receive an A grade for dissolved oxygen. This is good news for the Bay and its fish and shellfish populations.
Dissolved Oxygen in Water
Aquatic life, including fish and shellfish, requires oxygen to survive. How are the Bay’s watersheds doing?
What We Can do
Our Actions Impact Oxygen Levels
- Help preserve and restore habitats that help promote high oxygen levels, like forests and wetlands.
- Help prevent nutrient pollution by following the steps above to reduce nitrogen and phosphorus levels in Galveston Bay.
- Find out what else you can do about nutrient pollution.
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Galveston Bay Dissolved Oxygen
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Tributary Dissolved Oxygen
Essential for your favorite fishing hole
Want more? Check the grades on other Indicators.
Overview
Water Quality
Pollution Events & Sources
Habitat
Wildlife
Human Health Risk
Coastal Change
