Morris Dam & Reservoir

The Morris Dam is a 245-foot high concrete gravity dam. What holds the water back in gravity dams is gravity pushing down on the mass of the dam. Gravity dams have been in use for millennia, but it was the Romans back in 100 AD who have the honors of being the first to use concrete in their dams.

Built as a part of Los Angeles's massive flood control public works projects in the 1930s, the Morris Dam is used for flood control of the San Gabriel River in addition to groundwater recharge.

The front of the Morris Dam, showing the spillway on the right abutment, with the concrete dam to the right adjacent to the left abutment.

Close-up of the backside of the dam.


Looking south.


Looking upstream at the reservoir towards the north.

The San Gabriel River at the tail end of the reservoir behind Morris Dam, where the river is beginning to dam up. All of the fine-grained sediment is due to receding water.



Close up of the river, showing erosion along the river bank.