Studies show future gravity flow sewer system will have no environmental impact


The City’s engineering firm presented plans during a public hearing Monday on the upcoming construction of a gravity flow wastewater system in the area of Seward Junction.

Additional properties served by the system are on the east side of U.S. Highway 183 along State Highway 29.

The public hearing, which was required by law, served to educate the community on the history of the project and its potential environmental impact.

Engineer Perry Steger of the Georgetown firm Steger Bizzell made the presentation from a prepared statement to less than 10 people — most of whom were city staff, members of City Council or employees of the engineering firm.

While much of Liberty Hill is served by a pressure sewer collection system, Steger said his firm recommended the switch to a gravity flow system because it is more reliable.

“Gravity systems are more reliable systems with lower operating and maintenance costs,” he said. “Gravity systems also minimize maintenance requirements and odor problems while managing power outages better.”

Steger said the gravity system proposed for the Seward Junction area “should not raise connection fees or wastewater rates for customers.”

Environmental impact studies of the area were approved by nine agencies, he said. An archeological survey was requested by the Texas Historical Commission and a biological survey was requested by  Texas Parks & Wildlife and U.S. Fish & Wildlife Department.

Steger reported that the studies showed there was no impact of the future gravity flow wastewater system on land use, soils, geology, topography, floodplains, groundwater, threatened and endangered species, wetlands, known hazardous materials sites, farm lands, archeological and historical sites, unique environmental features, and socioeconomic and environmental justice.

With regards to surface water, the study found the potential runoff from the Edwards Aquifer Contributing Zone into the Recharge Zone would be mitigated by best management practices recommended by Texas Commission on Environmental Quality.

Taking care to avoid fence-row vegetation during the spring nesting period would mitigate the impact to nesting migratory birds, he said.

Standard erosion control measures would reduce potiential construction dust that might impact air quality, Steger reported.

The City began development of a wastewater system in 2002 and obtained loans from the Texas Water Development Board Clean Water State Revolving Fund. A $1.345 million Tier II loan and a $6.785 million Tier III loan were secured along with more than $1.3 million in Community Development Block Grant funds and $590,000 in STAG/SAAP grant funds.

To date, two construction contracts have been completed and a third has recently begun.

The first contract was for a pressure sewer system along the north side of SH 29, the second was a pressure sewer system for the downtown area.

The third phase, which is now under way, will be primarily a gravity system that will serve the Jenks Branch subdivision and the properties along Loop 332 on the west side of Liberty Hill.

Jody Giddens, a Leander resident who previously owned the property that is now the site of the Lower Colorado River Authority’s wastewater treatment plant, provided the only public comments of the evening.

He said his family has an ongoing  dispute with LCRA over the installation of sewer line from his adjacent property. When LCRA purchased the property from his family years ago, Giddens said it had agreed to complete the work, but never did.

The City of Liberty Hill is in the process of purchasing the plant from LCRA.

“We all believe the plant should belong to Liberty Hill,” he said. “There will be a need for additional lines and easements and it’s going to be expensive. We’re not going to be easy to work with until the problem is resolved.”

Steger said another engineering firm recommended in 2006 that the City install a pressure sewer system throughout the service area. When Steger Bizzell was hired three years later, it advised that a gravity system would be preferable.