 Santiago Creek would unleash seasonal floods in the winter and then while becoming a trickle or completely dry in the summer, making irrigation difficult.The Serrano Irrigation District was formed in 1928, and partnered with the Irvine Company and the Carpenter Irrigation District of El Modena, for the construction of Santiago Dam, impounding Lake Irvine.Construction work begun in 1929 and the dam was completed in 1931.