Environmental groups and residents near Austin’s proposed Dog’s Head development have sued the city and City Council, contesting a long-term agreement with developer Endeavor Real Estate Group and a tax-financing plan for the project east of downtown. The Save Our Springs Alliance, People Organized in Defense of Earth and Her Resources, and Dog’s Head neighbors filed the lawsuit Monday. It challenges Council’s unanimous May approval of a 45-year development agreement and its July creation of a Tax Increment Reinvestment Zone, or TIRZ. The development is planned for more than four square miles near Austin-Bergstrom International Airport. Under the TIRZ, Endeavor could be reimbursed for infrastructure costs with a portion of future property and sales tax revenue generated in the area. Estimates of the potential public commitment vary: one estimate puts it at $1.5 billion, while the lawsuit cites $2 billion. The plaintiffs say the amount is not capped and depends on future tax revenue. “The last thing Austin should be doing is diverting billions in future public revenue away from libraries, parks, public safety, and affordable housing to subsidize private development that was already moving forward,” PODER Executive Director Susana Almanza said in a statement. Endeavor said the project would turn a former sand and gravel mining site into a mixed-use community with jobs, housing, public infrastructure and more than six miles of public trails along the Colorado River. The company said it voluntarily annexed the property and that reimbursements would come only from new tax revenue generated by the development, not current tax dollars. The lawsuit argues the TIRZ does not meet state legal requirements because development in the area would occur without public assistance. It points to the site’s location near major highways, the airport and Tesla’s Gigafactory, and says the region is already experiencing rapid growth. The complaint cites a 2024 ruling involving a separate Austin TIRZ for redevelopment of the former American-Statesman site on Lady Bird Lake’s south shore. A Travis County judge found that plan violated state law because the area did not qualify for public financing under the requirement that development would not occur through private investment in the reasonably foreseeable future. The decision halted an estimated $354 million in future public revenue from going to developers, including Endeavor. The Dog’s Head plaintiffs also contend that the development agreement gives Endeavor powers that belong to the city, including influence over zoning, water quality and land-development rules. They argue the agreement lets the company veto regulatory changes affecting the property for 45 years, unlawfully restricting future City Councils. The lawsuit further challenges the approval process. It says the city first publicly referenced the project on May 8, published the agreement’s text on May 15 and approved it six days later, on May 21. The plaintiffs say residents had less than a week to review the agreement and that there were no prior public meetings, mailed notices to nearby residents or reviews by city boards and commissions. The case puts the city’s use of tax incentives and the limits of private developers’ control over public policy at issue as Austin considers a large new development near the airport and Colorado River.