Editor's Note: The above video is KXAN coverage from Jan. 29, 2024, when Rethink35 and other local organizations filed a lawsuit and civil rights complaint against the Texas Department of Transportation over the I-35 Capital Express Central project. AUSTIN (KXAN) -- State Rep. Gina Hinojosa, D-Austin, is calling on the federal government to intervene in the expansion efforts already underway along Interstate 35 near downtown Austin. The Texas Department of Transportation approved in August 2023 the expansion of the highway as part of the eight-mile, $4.5 billion I-35 Capital Express Central project. The state department celebrated the groundbreaking of that project Oct. 30, joining efforts already underway as part of the I-35 Capital Express North and I-35 Capital Express South projects. Despite TxDOT's approval of the project and work beginning, Hinojosa's letter to the U.S. Department of Transportation and Transportation Sec. Pete Buttigieg said there continues to be "overwhelming opposition to the selected alternative, which includes doubling the size of a highway linked to a century of racist practices." Hinojosa's letter references a federal complaint filed by Rethink35 and a coalition of other local organizations at the start of 2024, supplementing a lawsuit the groups filed against TxDOT. Rep-Hinojosa-Letter-10.28.24Download In Hinojosa's Oct. 28 letter, she highlighted specific concerns over TxDOT allegedly not studying: Environmental impacts on "concentrations of soot pollution," known as PM2.5 Heightened rates of asthma and cardiovascular disease in communities near the project corridor, citing a Dell Medical School study on disproportionately higher rates of both conditions in Black and Latino neighborhoods due to air pollution Parklands impacts, including the removal of trees from Pecan Grove, limited access to the Ann and Roy Butler Hike-and-Bike Trail, nearby community gardens and possible harm to aquatic and riparian life in Lady Bird Lake A TxDOT spokesperson declined to comment on the letter when asked by KXAN for a response. AUSTIN STITCHED TOGETHER: A divisive legacy lingers as I-35 expands Back in May, a group of Austin City Council delegates proposed to delay funding for the project, requesting additional environmental studies to be completed beforehand. That request -- made at a Capital Area Metropolitan Planning Organization's transportation policy board meeting -- was rejected by a majority of board members. Rethink35 leaders commended Hinojosa's letter in a Wednesday release. “Representative Hinojosa has stood up in a big way for our community,” Rethink35 board member Miriam Schoenfield said in the release. “We’re deeply honored by her courageous leadership and we hope Secretary Buttigieg acts swiftly to address the Representative’s -- and the community’s -- concerns.”