Firms offer green designs for Oak Hill, SH 45 SW

Earlier this year, the Central Texas Regional Mobility Authority invited engineering and architecture firms to try their hands at designing the environmentally sensitive projects.

CTRMA and the Texas Department of Transportation hosted the Green Mobility Challenge as a way to promote sustainability—designs that use fewer resources and exist more in-tune with nature.

Six finalists competed for two $15,000 prizes and the chance for their designs to be considered when the roadways are eventually built.

Team 1120—comprised of LJA Engineering, Coleman and Associates, Blanton and Associates and Construction Eco Services—won first place for its “Oak Hillway” design. The team imagined a united Oak Hill with a new highway, neighborhoods connected by underpass “gateways” and a relocated Williamson Creek.

Team 1175’s “Manchaca Greenway” won top honors for its elevated roundabout and integrated parklands.

CTRMA Communications Director Steve Pustelnyk said the mobility authority was excited about the ideas it received.

“Some, especially in Oak Hill, may not be reasonable or feasible, but there were some great ideas for roadway alignment, green space and parkway alignment. It’s really interesting,” he said.

The contest

CTRMA and TxDOT set out to raise awareness about how roadway designs can be more ecologically friendly, offer an opportunity for various professions to work together on mobility projects and encourage new problem solving.

Registration began during the summer, and eight teams submitted designs before the Oct. 13 deadline, said Mario Espinoza, CTRMA deputy executive director. Judges cut the list to six finalists in October.

The two agencies suggested that contestants focus on mobility, multimodal options, air and water quality and innovative hydrological designs, among other criteria.

Oak Hill

In the early 1990s, TxDOT planned to extend Hwy. 290 through Oak Hill. The project stopped because of public opposition, concerns about damage to the Edwards Aquifer and Williamson Creek, and eventually, a loss of funding.

Since then, several designs—tolled or not, six or eight lanes, raised or ground level—have been suggested.

CTRMA defined The Oak Hill Expressway as a controlled-access six- to eight-lane tolled highway with two- to three-lane frontage roads without tolls—the same definition the Capital Area Metropolitan Planning Organization expects to be built in the future.

In its presentation, Team 1120 representatives Ricardo Zamarripa and LJA Engineering owner Aan Coleman said Hwy. 290 divided Oak Hill’s neighborhoods in the 1990s.

“The Hillway approach to reconnect the community and recreate a vibrant sense of place will re-establish community support and economic sustainability,” Zamarripa said.

He expounded that their designs would raise Hwy. 290 and remake underpasses as “gateways,” multimodal links with aesthetic, environmental and historic features. The gateways would have native plantings, limestone bricks and solar lighting.

Each gateway would have a historic name relevant to nearby neighborhoods, Coleman said.

Team 1120’s plan also called for an Oak Hill Parkway, separate from Hwy. 290, that would connect shopping and mobility away from The Y at Oak Hill.

It also suggests a new multi-use town center and new open space. The plan would relocate Williamson Creek to allow for greater roadway flexibility, fewer bridges and better abilities to withstand 100-year storms.

The team estimated that their road design would save $5.8 million over 10 years.

Citing the company’s strong community ties, Zamarripa said the team plans to donate its prize money to the Oak Hill Wildfire Relief.

“We live, work and play in Oak Hill,” he said. “The community is ready for this project to be successful. We are ready to help with that project and unify Oak Hill with the help of TxDOT.”

SH 45 SW

Progress on SH 45 SW has moved slowly for at least two decades, according to Travis County Judge Samuel Biscoe.

During an interview for Community Impact Newspaper’s Coffee with Impact speaker series [see page 15], Biscoe said that he thought the project was a done deal in 1988 when he joined the Travis County Commissioners Court.

CTRMA defines SH 45 SW as a four lane, 3.6-mile tolled highway from MoPac to FM 1626 in southern Travis County. It is expected to have a U-turn interchange at Bliss Spiller Road.

Voters had approved bonds to purchase rights of way to connect MoPac and FM 1626. The project has been delayed since the 1980s.

Team 1175 representatives Ross Gordon and Jim Sipes described the Manchaca Greenway as a multimodal road made of recycled materials, with wireless toll collectors.

Their team’s design called for a double teardrop interchange, an elevated roundabout for U-turns. Nearby, a linear park would offer trail space, conservation areas, native plantings and educational opportunities.

The design featured tunnels where wildlife could cross underneath the highway without entering traffic. A so-called green shoulder with vegetative drainage ditches and layered biological filters would reduce runoff reaching the underground aquifer.

The team claimed the roadway would be among the most eco-friendly ever constructed.

Team leader Larry Ehlers said the challenge was a strategic win for his firm, AECOM.

“We were able to show the community and our clients that the company is working toward a sustainable future,” he said.

Going forward

While CTRMA and TxDOT are pleased with the ideas they received, it will be years before roadway designers can use them.

Pustelnyk cautioned that the contest was a very preliminary look at roadway design and that environmental studies alone typically take three years.

“We won’t actually look at design and construction for another four or five more years,” he said.

In Oak Hill, The City of Austin, Travis County, CTRMA and TxDOT are funding interim roadway improvements including continuous flow intersections, which separate turning traffic from through traffic.

City and county staff estimate that the interim fixes will be completed by winter 2013 and improve traffic for about five to seven years. The contest ideas would be considered for the longterm solution.

Whether SH 45 SW will be built in the near future is unclear.

The Capital Area Metropolitan Planning Organization expects that it will be built; It placed the project on its 2035 Regional Transportation Plan.

Biscoe said right-of-way acquisition and some engineering work has been done. He said environmentalists still oppose the road.

In September, the Hays County Commissioners Court proposed a plan to take the road out of the state highway system and build it locally with Travis County’s help. However, the Travis County Commissioners Court has not taken up the issue publicly.