SH 146 Kemah Expressway

With SH 146 serving as a major connector between Galveston and Houston, the SH 146 Express Bridge project held great regional importance for southeast Texas. The project involved the 4.3-mile widening and reconstruction of the existing highway into a six- to 12-lane highway and the addition of a new 2.1-mile, four-lane express bridge crossing over Clear Creek Channel at Galveston Bay. The existing ¾-mile bridge at Clear Creek, which is a tourist corridor and evacuation route, was widened. The project took place in an environmentally sensitive area surrounded by navigable waterways and wetlands. Grade separations were added at major intersections and access roads were added in selected locations.

The Texas Department of Transportation (TxDOT) trusted RS&H as prime construction engineering and inspection (CEI) consultant to maintain access throughout this busy corridor, minimize impacts to residents, and safely guide the project to an on-time delivery.

Maintaining Quality of Life for Locals

The Cities of Kemah and Seabrook and their residents stood to be impacted most by this project as active construction took place. RS&H and TxDOT used a partnering approach with the cities to prioritize the needs of the local community and maintain their standard of living during construction.

RS&H hosted meetings with city officials throughout the project to answer community questions and address items such as safety, traffic control plans, design changes, and modification requests. When phasing plans showed access impacts through the corridor, the team modified phasing to ensure two lanes of traffic remained open on SH 146 southbound coming into Kemah rather than one lane as initially planned. RS&H was also instrumental in coordinating side street closures to maximize access and minimize negative impacts for local travelers, and went above and beyond to adjust construction schedules, provide support, and maintain access during major community events, including foot races, Fourth of July fireworks, and boat parades. We also communicated with the Kemah Boardwalk – one of the region’s largest attractions – throughout construction and helped facilitate boardwalk traffic upgrades by including a new signalized intersection at 7th Street.

Thoughtful actions like these helped minimize the day-to-day burden placed on Kemah and Seabrook residents, businesses, and visitors. The expanded capacity is now facilitating community growth while residents and guests are enjoying the benefits of the roadway’s new capacity, with the new express lanes allowing port-bound trucks to bypass the area. The local landscape has changed dramatically, with the new divided freeway’s signature design elements serving to beautify the area.

Providing Innovative Solutions

To increase the long-term viability of the new bridge, Electrically Isolated Tendons (EIT) were utilized to encase prestressed tendons rather than conventional metallic ducts, which leave the tendons prone to corrosion. This innovative EIT system, which has been developed and tested in Europe, uses polymer ducts to encapsulate and electrically isolate two of the structure’s post-tensioned tendons and provide a leak-tight barrier against sources of corrosion. The system also facilitates inspection and enables long-term condition monitoring. RS&H worked with the system’s fabricator, VSL International, to learn and understand its intricacies. RS&H monitored the EITs throughout project closeout before passing control of long-term monitoring to TxDOT. Readings recorded after installation indicate that the system is successfully isolating the tendons from any corrosion-induced electrical charge.

RS&H also got creative to help the team overcome foundation challenges in the Clear Creek Channel. When the contractor was installing concrete piles in the Channel, they discovered underwater and underground obstructions that stopped work and created potential delays. RS&H determined the obstructions were 11-foot-thick concrete footings with piles from a previous drawbridge. To get the project back on track, RS&H reached out to several specialty foundation contractors and found one with a casing rotator capable of drilling through the massive existing foundations and piles, so drilled shafts could be installed instead of piles. Once on site, this powerful machine allowed the team to remove up to four feet of concrete per day and the project continued with no time impacts.

Overcoming Challenges to Bring the Project Home

No successful project comes without hurdles. Challenges throughout the project – including maintaining access, utility conflicts, and right-of-way acquisition delays – threatened to impact the project schedule and prolong the burden of an active construction project for residents and businesses. Fortunately, those fears were never realized thanks to proactive leadership from RS&H. Our project team helped TxDOT navigate $12M in change orders and work around impacts to construction sequencing to ultimately deliver the project on time.