New TPWD Rule requires All boats approaching or leaving Lake Houston to be drained

The Texas Parks and Wildlife Commission has approved a new regulation requiring that all boats operating on public fresh water anywhere in Texas be drained before leaving or approaching a lake or river to help combat the further spread of zebra mussels and other invasive species.

Zebra mussels on Lake Texoma and control efforts. Photo by Earl Nottingham
Zebra mussels on Lake Texoma and control efforts. Photo by Earl Nottingham

The rapidly reproducing mussels, originally from Eurasia, can have a serious economic, environmental and recreational impact on Texas reservoirs. Zebra mussels can clog public-water intake pipes, harm boats and motors left in infested waters by covering boat hulls, block water-cooling systems, annoy lake property owners by completely covering anything left under water, and make water recreation hazardous because of their sharp edges.

With the destructive invasive species having spread to Lake Belton, conservation officials and water-supply agencies are very concerned that zebra mussels could expand their range throughout the state, including Lake Travis and the other Highland Lakes.

“Zebra mussels have been moving steadily deeper into Texas since they were first found in Lake Texoma in 2009,” says Brian Van Zee, the Texas Parks and Wildlife Department’s Inland Fisheries Division regional director who has spearheaded the agency’s response to zebra mussels in Texas. “Now that they are in Lake Belton, the Highland Lakes are in the cross hairs as are many of the public waters in Central Texas.”

David Cowan, Lower Colorado Authority senior water quality coordinator, says the LCRA routinely monitors the Highland Lakes.

“So far we haven’t seen any evidence of zebra mussels,” Cowan said. “We will continue working closely with Texas Parks and Wildlife in urging the public to help us keep zebra mussels out of the Highland Lakes. The mussels not only are a nuisance, but they could pose serious operational problems for the dams, water intake structures and the general health of the lakes.”

While the new measure won’t take effect until July 1, TPWD urges all boaters to begin the preventative practice immediately since microscopic larvae (called veligers) hiding in your boat can travel to another water body and cause a new zebra mussel infestation.

Currently in effect in 47 North and Central Texas counties, the new rule requires persons leaving or approaching public water to drain all water from their vessels and on-board receptacles. This applies to all types and sizes of boats whether powered or not, personal watercraft, sailboats, kayaks/canoes, or any other vessel used on public waters.

“The way to comply with this requirement is simple,” Van Zee said. “All you have to do is clean, drain and dry your boat. This is critical, because in their initial state, zebra mussels are invisible to the naked eye.”

The soon-to-be statewide rule, which is similar to those in other states impacted by zebra mussels, is based on the fact that trailered boats tend to be the most likely way zebra mussels get from one water body to another. Since boaters in Texas travel throughout the state to engage in various forms of recreational activity, from skiing to fishing, the rule has been made statewide.


The regulation also requires the draining of live wells, bilges, motors, and any other receptacles or water-intake systems coming into contact with public waters.

Live fish, including personally caught live bait, cannot be transported in a vessel in water that comes from the water body where they were caught. Personally caught live bait can be used in the water body where it was caught.

Anglers are allowed to transport and use commercially purchased live bait provided persons in possession of the bait have a receipt that identifies the source of the bait. Any live bait purchased from a location on or adjacent to a public water body that is transported in water from that water body could only be used as bait on that same water body.

The rules allow anglers participating in a fishing tournament confined to one water body to transport live fish in water from that single water body to an identified off-site weigh-in location, provided all water is drained and properly disposed of before leaving that location. Anglers are required to possess documentation provided by tournament organizers that would identify them as participants in the tournament.

In a related story – “Inspectors nab Texas houseboat in Oregon with invasive quagga mussels” — The Malheur County Sheriff’s Office helped keep an invasive species out of Oregon on Tuesday by nabbing a driver hauling a Texas houseboat in Ontario. The pontoon houseboat was infested with juvenile quagga mussels. The Pacific Northwest is the only area in the country that has no quagga or zebra mussels in any of its waterways, said Rick Boatner, invasive species expert at the Oregon Department of Fish and Wildlife. Read more 

Movement from one access point to another on the same lake during the same day does not require draining and there is an exception for governmental activities and emergencies. Marine sanitary systems are not covered by these regulations.

“The BRA supports the efforts of the Texas Parks and Wildlife Department and will continue to assist them in preventing the spread of mussels to our system reservoirs,” said Phil Ford, general manager and chief executive officer for the Brazos River Authority.

Zebra mussels became established in Texas in Lake Texoma in 2009. In 2012, they were found in Lake Ray Roberts and the Elm Fork of the Trinity River. Last year, zebra mussels spread to Lakes Bridgeport, Lavon, Lewisville, and Belton. From an environmental perspective, zebra mussels are filter feeders that compete with baitfish such as shad for available forage. Any impact on baitfish in turn can affect their predators — game fish such as bass, striped bass and catfish. Zebra mussels also threaten native mussel populations because they colonize on their shells and essentially suffocate them.

“Zebra mussel infestations may also be related to blooms of toxic blue-green algae,” Van Zee said. “In 2011, Lake Texoma was closed to swimming for a time because of an outbreak of blue-green algae. The bottom line about zebra mussels is that they are bad news for Texas and we need to do everything we can to stop their spread.”

TPWD and a coalition of partners are working to slow the spread of zebra mussels by reminding boaters to Clean, Drain and Dry their vessels before traveling from one lake to another. The partners in this effort include: North Texas Municipal Water District, Tarrant Regional Water District, City of Dallas Water Utilities Department, Trinity River Authority, San Jacinto River Authority, Sabine River Authority, Brazos River Authority, Guadalupe-Blanco River Authority, Lower Colorado River Authority, Upper Trinity Regional Water District, Canadian River Municipal Water Authority, City of Grapevine, Water Oriented Recreation District of Comal County, and the Lady Bird Johnson Wildflower Center.

More information, including where water draining regulations are currently in effect, is online at

Photos by Texas Parks and Wildlife Department