In response to significant monsoon-related flows observed in 2014 and 2017, the District has initiated an update to its original San Tan West Area Drainage Master Study (ADMS) completed in 2012 to specifically address recent changes in the watershed, including conversion of native desert and agricultural lands to commercial and residential land uses. The update is also intended to model the impacts that roadway improvements and flood control facilities constructed after the completion of the ADMS have had. The updated ADMP model will be used to locate, identify and quantify potential flood hazards and provide a roadmap for designing appropriate flood hazard mitigation alternatives.
The District is currently compiling new aerial topographic mapping and surface feature characterization for the entire watershed. The District is planning to advertise for professional engineering services in early 2019 to update its hydrologic models for the watershed, enabling us to identify alternatives for mitigating the area's most critical flood hazards. One public meeting was held in early 2018, and a second public meeting will be scheduled shortly after our issuance of a Notice to Proceed (NTP). We expect this update to be completed within 36 months of this NTP.