GIS Puts Culver City Sewer Maps in their Place

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By Jessica Wyland | 18 January 2010 | 10628

Like a lot of small towns, the effects of time and growth compromised Culver City’s public works data, especially the city sewer system. In 2007, a committed collaboration between the Public Works Department  and the Culver City Information Technology Department began to update citywide sewer maps. The redevelopment of the sewer data is ongoing using geographic information system (GIS) technology from ESRI.

Harry H. Culver started making plans in 1913 for the city that carries his name. Culver City, California was officially established in 1917, halfway between the cities of Los Angeles and Venice. Buoyed by a strong economic base of movie studios, small businesses, and industrial endeavors, the city grew to include more people, more land, schools, and city government. By the year 2000, the city had quadrupled in size and is now a community of nearly 40,000 residents.

The effects of time and growth compromised Culver City’s public works data, especially the city sewer system. When Marcos Mendez accepted an internship in 2007 at the Culver City Information Technology Department, he began a committed collaboration with the Public Works Department to update citywide sewer maps. Mendez started by redeveloping sewer data using geographic information system (GIS) technology from ESRI.

The Sewer GIS Mapbook shows detail information of the city's waste water infrastructure.

Compiling Sewer Plans
Mendez started the process by looking at all of the city’s sewer as-built plans and profiles. This was a real challenge since the city does not have a staff member dedicated to full-time maintenance of sewer plans. Mendez cobbled together sewer plans from various files including street plans, tract plans, and parks and recreation records. One thing Mendez had working for him was the city’s mature GIS program, replete with many datasets developed over a span of more than 10 years. This information ensured greater accuracy and provided aerial photography for cross referencing.

A goal of the project was to hyperlink sewer plans to the GIS sewer line so that the data would be accessible via a Web application. When a user visits the city Web site, the Web application would display the sewer map. With a click on a sewer line, the user could retrieve a scanned PDF of the as-built.

Since Culver City was founded in 1917, some of the original sewer plans were missing. Other plans, dating back to 1922, were very difficult to scan internally so the city completed that portion of the project through contracted experts. However, there were still blanks to be filled.

“We used numbers in each field within the GIS data to designate the status of sewer plans,” Mendez explained. “For example, I would place a 0 in the attribute information if the sewer line was OK. A 1 means it is missing a sewer plan. A 2 means the plans could not be scanned and needed to be contracted out. A 3 indicated there was a question for the sewer maintenance manager.”

Mendez coordinated as-built plans with sewer lines where possible. If he could not find a match, Mendez used aerial images or GPS data to georeference the location. Culver City engineers checked every single line and point to ensure accuracy before approving the data.

The Online Sewer Access System Map makes it easy for  users to retrieve scanned sewer AS-BUILT plans.

A Job Well Done
Because of diligent GIS work, Culver City now has an up-to-date Citywide Sewer GIS Map Book and a Web application to share the data with the public.

“Our Sewer GIS database has increased productivity and propagated better information flow a thousand fold,” said Johnnie Griffing, GIS Project Manager. “Thematic maps are now generated that depict entire portions of the system as connected to each pump station. This was a big revelation for engineers and field crews who had not previously had a means for visualizing the extent of the sewer system’s relationship to pump stations. The map book offers a fine level of detail previously only available by retrieving and viewing hundreds of paper drawings—reflecting the most current and staff-verified picture of sewer distribution as it is in the field. Management can now review these details of the system to make better decisions.”

The Online Sewer Access System map shows sewer pipes, flow direction, manholes, aerial imagery, parcels, pump stations, pumps, and wet wells. GIS layers are served on top of city infrastructure layers such as streets and city boundaries. Users can navigate based on address or intersection, click on a line or point, see the attribute information, and view associated scanned drawings that have been hyperlinked.

Through ArcGIS, The City of Culver City was able to develop The Sewer GIS Mapbook.

The city’s sewer data now includes material, footage, year installed, tributary, and ownership data. All pipes have documented material, size, and diameter, as well as digitized outfalls from the city of Los Angeles. There is also manhole data such as cleanouts and lamp holes, not included in previous versions of sewer maps. Mendez is currently adding manhole identification to the data which will further assist field crews. To improve functionality of the Web application, the city plans to launch ArcGIS Server by the end of this year.

“GIS made everything come together,” Mendez said. “Culver City staff can go into the Web application and access everything they need from one system. GIS is saving us a lot of time because we don’t have to dig through cabinets for information or rely on memory.”

Jessica Wyland is a writer at ESRI; e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it. This e-mail address is being protected from spambots. You need JavaScript enabled to view it