Get in. Have fun. Be safe.

Reservoirs and rivers in Texas are natural systems. They are not chlorinated and they are habitats to naturally occurring life forms. The majority of the life found in the water is not hazardous to humans, but there are a few things to be aware of.

General Information

Water safety
PAM is a disease caused by the Naegleria fowleri ameoba. It is a naturally occurring organism found in warm freshwater bodies of water. The ameoba must be inhaled through the nose to be dangerous. To minimize the risk of contracting the ameoba, avoid swimming or splashing in shallow, stagnant areas of water when water temperatures are warm. To obtain more information about Naegleria fowleri and PAM in Texas, please review this information provided by the Texas Department of State Health Services.
Another organism that is commonly found in water but can on occasion be hazardous to human health is blue-green algae. As a group, these algae can be found in almost all fresh waterbodies, but the genus and population density can vary greatly. Certain types of blue-green algae can produce toxins that when found in high density populations can be hazardous to humans. The effects of the algae can vary greatly from mild skin irritation to respitory effects. No toxin from algae has ever been documented in a TRWD reservoirs, but the algae populations vary greatly through the lake and seasonally throughout the year. To minimize any risk, avoid swimming in areas where visible mats of green scum can be seen on the water.
This small freshwater mussel whose American population began in the Great Lakes has steadily been migrating south and west for many years. Within the last few years, they have been confirmed in the West Fork Reservoirs of the TRWD system, Bridgeport and Eagle Mountain. While these animals do not pose any human health risk, they are an invasive species and it is important to know when you are recreating in inhabited waters to minimize the risk of transport. For information on how to properly disinfect boats and trailers and additional information regarding zebra mussels, please visit the Texas Parks and Wildlife Department information page.

Trinity River

A dynamic system

The Trinity River in Fort Worth is host to many recreational activities throughout the year. This major river as well as smaller creeks and tributaries can be great places for fishing, boating and swimming; however, these waterbodies also have special safety concerns due to the dynamic characteristics associated with rivers and streams.

Rivers and streams are not steady state systems. The flows associated with each one can vary greatly depending on weather and upstream reservoir operations. The speed and strength of a moving water body is easily underestimated. If there has been a recent increase in the flow and velocity of a waterbody, exercise caution and wait for the water to return to normal levels before entering the water. To check current flows of major streams, please visit the USGS realtime streamflow webpage for current conditions.

Another hazard that is often overlooked in riverine systems is pollutant loads associated with bacteria levels. Often times, increased flow in rivers and creeks is caused by runoff from storm rainfall events. As the rain washes over the surface of the land, the water picks up pollutant loads from the surface of the ground and carries it to the river. During rain events and in recent days following a storm, pollutant loads can be higher than normal, which can cause a higher than normal risk to human health. The health risk is monitored through measuring the levels of Escherichia coli (E. coli) in the water. This bacteria itself is not harmful, however it is specific to warm blooded animals and is used as an indicator species. Therefore, if there are elevated levels of E. coli, the potential risk of something that could be harmful to human health is perceived to be greater. E. coli concentrations are measured monthly at nine locations year round and weekly at the five locations in the vicinity of the greatest recreational activities from April to August. The results of the E. coli sampling program can be viewed here.