The I-45 mainlanes will eventually go over new lanes of FM 646.
The I-45 expansion project between FM 518 to FM 517 in League City/Galveston County will begin a major milestone on Friday, March 1 as crews begin demolition of the FM 646 bridge over the mainlanes of I-45.
As part of the project, the existing I-45/FM 646 intersection will be converted so that FM 646 will go under the mainlanes of I-45. The intersection will be constructed in two phases. The first phase will include the demolition of the FM 646 overpass, construction of the I-45 northbound mainlane overpass, and reconstruction of the intersection and frontage roads.
Following the first phase of construction, the intersection will be reopened to east/west traffic and the frontage roads will be reconstructed along with the I-45 southbound mainlane overpass. Beginning on Friday, March 1 at 9 p.m. the FM 646 bridge at I-45 will be permanently closed. In addition, two northbound mainlanes from FM 517 to FM 646 will be closed beginning on Friday, March 1 at 9 p.m. until midnight on Saturday, March 2.
During the closure of FM 646 at I-45 traffic will be detoured to the frontage road. Those traveling westbound on FM 646 will travel onto the I-45 northbound frontage road to SH 96, u-turn and travel on the southbound frontage road to FM 646. Those traveling east bound on FM 646 will travel onto the I-45 southbound frontage road to FM 517, u-turn and travel on the northbound frontage road to FM 646.
This portion of the I-45 expansion project is anticipated to take approximately six months to complete. The I-45 expansion project between FM 518 to FM 517 will improve mobility for motorists while reducing congestion and improving safety along this heavily traveled corridor. The corridor changes will also aid in facilitating the growth and development of Galveston County, and will provide the capacity to support the anticipated future growth of the surrounding communities.
The $122 million project began in late 2016 and it is expected to be completed in early 2021. For more information on this closure contact Danny Perez at danny.perez@txdot.gov or (713) 802-5077. Also be sure to visit the Houston TranStar website at www.houstontranstar.org for a complete list of closures related to this construction project and other Houston District closures. All closures are subject to change due to inclement weather. Follow us on Twitter @TxDOTHouston.