GRS was contracted by the Central Contra Costa Sanitary District for the development of a schematic sewer system database suitable for modeling, monitoring, and analyzing the District’s sewer facilities. Other objectives were the development of permit/parcel relationships and main/lateral/parcel relationships.
This project consisted of five major components:
- The review and modification of database definitions and standards; the creation of a GIS-ready sewer main/structure network (FROM/TO) database;
- The labeling of the sewer facilities;
- The placement and the development of spatial relationships linking sewer laterals to parcels and mains; and
- The input of sewer permits and the development of spatial relationships relating the sewer permits to parcels.
This project required the conversion of over 600 1":100' “as-built” sewer system maps into a digital format compatible with Intergraph's Modular GIS Environment (MGE). The final database consisted of over 39,000 mains, 36,000 structures, 68,000 laterals, and 114,000 permits. All data were feature tagged and cleaned, resulting in topologically correct data. The X,Y coordinates of both mains and structures were placed coincidently and all graphic elements were edge matched between adjacent design files to ensure sewer system network connectivity. Relational joins between laterals, mains, and parcels, and permits and parcels were generated using GRS processes based on the graphic identification of the appropriate map elements. GRS developed numerous shell scripts and data-driven commands to automate and simplify map conversion and attribute input/reconciliation efforts and minimize the capture of erroneous data.
