San Antonio Dam (San Bernardino County)

{{Infobox dam

| name = San Antonio Dam

| name_official =

| image =

| image_size =

| image_caption =

| image_alt =

| location_map =

| location_map_size =

| location_map_caption =

| location_map_relief =

| coordinates = {{coord|34|09|27|N|117|40|41|W|type:landmark|display=inline,title}}

| country =

| location = San Bernardino County, California

| purpose = Flood and debris control

| status =

| construction_began = {{start date and age|1952}}

| opening = {{start date and age|1956}}

| demolished =

| cost =

| owner = 24px U.S. Army Corps of Engineers, Los Angeles District

| dam_type = Embankment

| dam_height = {{convert|160|ft|m|abbr=on}}{{cite web|url=http://ce-npdp-serv2.stanford.edu/DamDirectory/DamDetail.jsp?npdp_id=CA10023|title=San Antonio Dam|publisher=Stanford University|work=National Performance of Dams Program|date=|accessdate=2014-01-01}}

| dam_height_thalweg =

| dam_height_foundation=

| dam_length = {{convert|3850|ft|m|abbr=on}}

| dam_width_crest =

| dam_width_base =

| dam_volume =

| dam_elevation_crest =

| dam_crosses = San Antonio Creek

| spillway_count =

| spillway_type =

| spillway_capacity =

| res_name =

| res_capacity_total = {{convert|11880|acre feet|m3|abbr=on}}

| res_capacity_active =

| res_capacity_inactive=

| res_catchment = {{convert|27|mi2|km2|abbr=on}}

| res_surface =

| res_elevation =

| res_max_depth =

| res_max_length =

| res_max_width =

| res_tidal_range =

| plant_operator =

| plant_commission =

| plant_decommission =

| plant_type =

| plant_turbines =

| plant_capacity =

| plant_annual_gen =

| website =

| extra =

}}

San Antonio Dam is an embankment flood control and debris dam on San Antonio Creek in San Bernardino County, California, about {{convert|5|mi|km}} north of Ontario. The dam was authorized by the Flood Control Acts of 1936 and 1938 as part of a major program to provide flood protection in the Santa Ana River system. Construction began in April 1952 and finished in May 1956. The dam controls runoff from a rugged catchment area of {{convert|27|mi2|km2}} in the San Gabriel Mountains.{{cite web

|url=https://www.spl.usace.army.mil/Missions/Civil-Works/Media/FactSheets/Article/477345/dam-safety-program/

|title=Dam Safety Program: San Antonio Dam

|publisher=U.S. Army Corps of Engineers

|date=

|access-date=2014-01-01}}

The dam was built by the Los Angeles District of the U.S. Army Corps of Engineers. The dam is {{convert|3850|ft|m}} long, {{convert|160|ft|m}} high above the foundation, and {{convert|130|ft|m}} above the riverbed. The main embankment contains {{convert|6050000|yd3|m3}} of material. The reservoir behind the dam is usually dry, but can fill with up to {{convert|11880|acre feet|m3}} of water after large flooding events. A concrete overflow spillway on the west side prevents overtopping and drains to the San Antonio and Chino Creek channels, which were lined with concrete between 1956 and 1960 to protect against such an event.

A project has been underway since 2012 to remediate seepage problems at the toe of the dam during heavy rainstorms. The dam is considered a high hazard structure.{{cite web

|url=https://www.spl.usace.army.mil/Media/Fact-Sheets/Article/san-antonio-dam-saftey-ca/

|title=San Antonio Dam Safety, CA

|publisher=U.S. Army Corps of Engineers

|date=2012-07-27

|access-date=2013-01-01}}