City of Santa Cruz Storm Water Inflow and Infiltration Study

Client: City of Santa Cruz

Prime Contractor: E2 Consulting Engineers

Location: Santa Cruz, California

Period of Performance: January - July 2006

Project Description: The City of Santa Cruz (City) conducted an inflow and infiltration (I&I) study of its sanitary sewer system in an attempt to quantify the degree of which storm water is contributing to overall sewer volume flows. Twenty-five flow meters were installed throughout the City's sewer conveyance system. Three rain gauges were also installed within the study area. These instruments continually monitored sewer volume flow and rainfall totals for the entire six-week study duration. Field verification with hand-held flow meters was performed to calibrate in-situ electromagnetic and ultrasonic flow instrumentation. Wet-weather and nighttime field operations were also performed for a complete temporal data set.

ADH Responsibilities: ADH staff were responsible for assisting in equipment installation, monitoring, data acquisition, and demobilization for the entire project. Self-contained, internally data-logging flow meter and rain gauge instruments were deployed to provide time-series analyses of inflow and infiltration. Wet-weather and nighttime real-time measurements of flow were collected to calibrate in-situ meters under a wide range of flow conditions. Additionally, ADH personnel participated in confined space entry necessary for gaining access to the monitoring points.