A GIS-Centric Approach to Building a Water/Sewer/Storm Geodatabase
Oakland County, Michigan, Drain Commission Prepares Well for Infrastructure GIS
Oakland County, Michigan, officially came into being in 1819. Now, 184 years later, it is considered part of the greater Detroit area and is a hotbed of the automotive industry. The county has 11 parks covering 89,000 acres and 1,468 natural lakes. Its population is approximately 1.2 million, and it is home to 60,000 businesses and government agencies, employing nearly 800,000 people. By 2030, the county is expected to grow by 14 percent.
A vital component of all this diversity is the Oakland County Drain Commission (OCDC), which operates and maintains water, sewer, and storm systems for a noncontiguous service area of approximately 600 square miles. Oakland County's significant commercial and residential development demands improved infrastructure planning to ensure adequate drainage and minimal impact on infrastructure systems.
Implementing an infrastructure management GIS has been a primary goal for John P. McCulloch, Oakland County drain commissioner. In fact, he has launched other customer service initiatives recently-such as ISO 9002 certification-to be more responsive to communities served by OCDC.
Sound planning has always framed the efforts of OCDC, which internally completed a GIS Project Implementation Plan in 2000. It continues to build upon its infrastructure management GIS after completing an 18-month planning process. At the beginning of the project, OCDC got budgetary figures for data conversion and application development but focused on finding the best team to plan the project.
The winning team was led by Esri Business Partner Woolpert LLP (Dayton, Ohio), selected for its infrastructure GIS development, planning, database design, and conversion expertise. Other team members included Esri Business Partner KEMA Consulting (Fairfax, Virginia), chosen for its experience in database design, business process reengineering, and object-oriented data models; and Esri, which brought experience with ArcGIS core technology. OCDC's GIS is based on a comprehensive technology plan, geodatabase design plan, and conversion plan developed by the Woolpert team.
"When we began our planning, ArcGIS technology was new to our user community," says Scott Oppmann, GIS utility supervisor in the county's Information Technology Department. "We had been exposed to ArcGIS 8.0 in beta, but we wanted to make sure Esri was tightly coupled with the solution so everything we developed would work efficiently in ArcGIS."
OCDC's approach was GIS-centric: to build a single system to manage and store spatial and tabular infrastructure data and support engineering and construction, operations and maintenance, and financial and administrative applications.
"Everything we do is based on our infrastructure records, but we've always had to work from hard copies, scanned files, AutoCAD files-a lot of unrelated data sets," says Jenny Shaw, OCDC's GIS project manager. "That's why GIS should be at the center of our organization, feeding all other tasks."
Woolpert, KEMA, and Esri collaborated to ensure the best possible geodatabase design. They began with Esri's ArcGIS infrastructure data models and customized them for OCDC's needs. The team considered issues such as how to handle virtual features-connectivity elements needed for network analysis that don't exist in the real world-and proposed and abandoned features.
Serving 61 Cities, Villages, and Townships
Not only is OCDC's water/sewer/storm infrastructure GIS being integrated with the county's overall GIS, but it's also been designed to serve the infrastructure management needs of all 61 cities, villages, and townships (CVTs) within the county-half of which fall outside OCDC's service area.
"Our challenge for long-term compliance with water quality, the National Pollutant Discharge Elimination System (NPDES) Program Phase II, and other federal and state regulations is to build one large, integrated infrastructure management system, and to do this, we have to integrate data from the county's more than 30 CVTs that have their own departments of public works and maintain their own infrastructure," says Oppmann. "We're all in this battle together. If we can work cooperatively to address water quality and other environmental issues, we'll be able to identify where the problems are and make the right improvements to our infrastructure."
John Przybyla, Woolpert's project manager, says the design team took advantage of the power of the geodatabase. "We imposed quality control at the beginning of the process through the rules, behaviors, and domain values we built in the geodatabase. You spend your time creating behaviors, and these behaviors are embedded in the database design. With this new capability comes a much higher requirement to do your thinking during the database design stage, and that makes the process longer, harder, and more intensive, but much more rewarding."
Simplicity in the geodatabase design leads to better functionality, Oppmann adds. "You can do a lot of great things with geodatabases and relational database technologies, but how well are these going to perform in the GIS world? Esri's best advice to us was to minimize subtypes and physical database relationships so you don't create performance issues."
Esri's geodatabase concept is exciting stuff for utilities, Przybyla continues. "What's important in the utility world is that network features have defined behaviors, such as connectivity and flow, at the feature level. You can do tracing operations, basic network operations. Before ArcGIS, we didn't have that intelligence at the feature level-we had to build custom applications to do this. Today with ArcGIS, if you use network feature types, network tracing is an off-the-shelf function."
Shaw said the geodatabase design process helped OCDC improve business work flows through process improvements. "The geodatabase design brought everything into sharp focus," she says. "It's been more of a people project than a technology project-hours and hours of sitting down with people, doing interviews, capturing the data, deciding what was valid to include in the geodatabase and what really didn't have a place. People understand their business like they never did before."
Oppmann says a utility should be prepared to spend plenty of time customizing domain values, a task best performed by users, those who have the most intimate knowledge of their infrastructure systems, not consultants.
"If you're going to use the geodatabase to validate data, domains must be accurate and designed for the local area," Przybyla says. "Someone else's domains won't work for you."
The next steps include application development and full deployment. In the meantime, OCDC's information technology is being standardized according to the Technology Plan-with standard PCs and equipment, network improvements, and database consolidations. OCDC is currently running ArcGIS 8.2 on 12 Dell desktop PCs.
Oppmann says OCDC will continue being successful because of proper planning, core technology improvements, and a strong data model-one that's taken future users into account. "The infrastructure data model is open, scalable, flexible, and maintainable," he says. "We can add attributes and extend it with a computerized maintenance management system. We are comfortable it will meet everyone's needs, both in the Drain Commission and elsewhere throughout the CVTs, because we included them in the planning and model review process."
Shaw agrees. "We wanted to provide more than just a starting point," she says. "We wanted to provide an outstanding product to our internal staff, customers, and all the communities in Oakland County."
For more information, contact Scott Oppmann, Oakland County (tel.: 248-452-9198, e-mail: email@example.com), or John Przybyla, Woolpert (tel.: 800-414-1045, e-mail: firstname.lastname@example.org).