Overview

The WAA sanitary collection system was constructed between the 1970s and early 2000s. Older parts of the system were experiencing severe inflow and infiltration (I&I) of groundwater into the sewer pipes, causing otherwise clean groundwater to be sent to, and treated at, their wastewater plant. Comprehensive mapping and inspection of their system provided the information necessary to pinpoint the I&I problems, and develop rehabilitative measures. In addition, WAA desired to use Geographic Information System (GIS) to access the mapping and provide a repository for documentation related to their infrastructure.

Field data collection with sub-meter accuracy GPS was used to locate manholes, valves, pump stations, and the outfalls. The system-wide inventory was compiled in a GIS geodatabase. Manhole inspections were conducted in conjunction with the field data collection. The manhole condition assessment information and associated photos were linked to the manhole inventory.

A GIS web map was created and configured in ArcGIS Online. The web map features access to collection system mapping, as-built drawings, condition assessments, photo documentation, and lateral reports. Reporting tools allow WAA to filter their assets based on type, material, size, or condition. The reports can be output to maps and tables for field use, communication with staff, or coordination with contractors. WAA now has access to the necessary information to make more informed decisions when planning for, and investing in, their system.