Condition Assessment of an Urban Spillway Designed and Built in Three Phases Spanning 45 Years

Puddingstone Dam, Los Angeles County California, was constructed in 1927-28 for flood control and water conservation with an auxiliary spillway consisting of an uncontrolled mass concrete weir and 285-foot long training walls and reinforced concrete slab (Phase I) that discharged onto sloping ground ~500 feet from the embankment dam. Following a major 1938 storm, the concrete spillway chute was extended 115 feet in 1944 (Phase II) and included a bridge for the access road. A public water park, constructed in 1971 downstream of the spillway, included an 800-foot reinforced concrete extension of the spillway chute with a grouted riprap structure at its Puddingstone Creek junction (Phase III). A 2018 condition assessment inspection identified the Phase I spillway weir, slabs, and walls to be in satisfactory condition; the Phase II and III slabs and walls and grouted riprap structure to be in good condition; and the inspected drains to be in poor condition. The spillway remains nonactivated throughout its 95-year history.