After decades of going back and forth, a $25M settlement has been reached between environmental groups and Orange County's Five Point Holdings regarding the huge Newhall Ranch development.

The Santa Clarita project can now move forward.

The $13B, 21,500-unit Newhall Ranch project is considered to be the largest subdivision of its kind nationwide, the LA Daily News reports.

The settlement was reached with the Wishtoyo Foundation, the Center for Biological Diversity, the Santa Ynez Band of Chumash Indians and the California Native Plant Society.

It includes protecting the endangered unarmored three-spined stickleback fish,  creating the Santa Clara River Conservation Fund and preserving the culture of the Santa Ynez Band of Chumash Indians and the Wishtoyo Foundation.

The LA County Board of Supervisors approved plans for two out of the five villages last July that are part of the Newhall Ranch development.

The Santa Clarita Organization for Planning and the Environment and Friends of the Santa Clara River did not participate in the settlement and say they will continue to fight the development.

The organizations filed a complaint in August, complaining about water availability in the neighborhood and concerns about air pollution.

Five Point Holdings could break ground a month from now, KABC reports.