Aspen prepared the EIS/EIR to support a Corps of Engineers feasibility study for the removal of Matilija Dam on Matilija Creek, which is a tributary of the Ventura River.

Under contract to California Trout and in partnership with California Department of Parks and Recreation (CDPR), Aspen prepared the Rindge Dam Removal Pathway Risk-Benefit Assessment.

Under contract to the California Department of Water Resources (DWR), Aspen Environmental Group prepared an Environmental Impact Report (EIR) for a proposal to change the seasonal flow release schedule of Pyramid Dam, located at the southern end of Pyramid Lake in Los Angeles County, California.