Modesto Effluent Storage, located in Stanislaus County, California, is a crucial water resource infrastructure managed by the local government. Completed in 1987, this offstream Earth dam stands at a height of 20 feet and has a storage capacity of 7830 acre-feet. Its primary purpose is to supply water for various uses including flood risk reduction and water supply in the San Joaquin River area.

The dam's significant hazard potential is mitigated by regular inspections, with its condition assessed as satisfactory as of September 2017. The structure's inspection frequency is once per year, ensuring its safety and reliability for the surrounding community. Owned and regulated by the state of California, Modesto Effluent Storage plays a vital role in water management and infrastructure development in the region.

With a surface area of 596 acres and a drainage area that aids in flood risk reduction, this dam serves as a key component in the state's water resource management. Its location in the San Joaquin River area, along with its design and capacity, highlights the importance of sustainable water storage infrastructure in mitigating climate change impacts and ensuring water security for local communities.