Can You Dig It?

GIS system stops redundant street excavations in Sacramento County, Calif.

by / September 7, 2006
It's the kind of faux pas that makes a taxpayer's blood boil -- a utility closes a street to service underground cables. When the project is done, workers repave the roadway. Five weeks later, the Department of Public Works digs up the freshly paved surface to work on a sewer line.

This failure to coordinate means twice the inconvenience for anyone who regularly drives on that street, and the double excavation and repaving also waste money.

Like many local governments, Sacramento County, Calif., dealt with this sort of blunder all the time. However, in the late 1990s, a county supervisor got annoyed about traveling on a road that had just been excavated and was being excavated again, said Bob Earle, the county's principal IT analyst.

At the time, county officials had no formal method for coordinating excavation projects. The procedure was entirely reliant on one person remembering to call another, Earle said, adding that turnover was a problem as changes in staff interrupted the chain of personal communications. "So things got excavated twice."

To address this challenge, the county's Geographic Information Systems (GIS) department started building support for the idea of developing software that county departments could use to coordinate street excavation projects. The first version of the county's Street Excavation Right of Way (SEROW) system went on line in 1999, and in 2003 -- with help from GeoPrise.Net, a developer of GIS applications for governments -- Sacramento County started using a second, more capable version of its SEROW system.

County developers originally built SEROW using ArcIMS, a software solution from ESRI, for delivering GIS data and maps over the Web. After substantial thought about how to display the areas covered by excavation projects, they decided to use street centerlines. That's not a perfect choice, since a project might correspond to more than one road segment, but "it seemed to be the most practical and useful feature we can tag these projects to," Earle said. "The centerline is one of our fundamental base map layers, so it's updated on a frequent basis and is useful in a lot of applications."

GeoPrise.Net, a reseller of ESRI software, later rewrote SEROW from scratch, basing it on standard technologies so it can evolve as the available technology improves, said Mark Perry, president of GeoPrise.Net. In the SEROW system, GeoPrise.Net provides the business and presentation logic while ArcIMS provides the map displays.

One important change in the new system is that it allows project managers to enter data about street excavations themselves, rather than relying on the GIS department to update SEROW on their behalf.

But the No. 1 change was in system performance, Perry said. "It was the most important improvement in terms of user acceptance and software effectiveness. It was too slow prior to that -- so slow that staff resisted using it. We improved the interface and tools for editing the project data quite a bit."

That's Going On?
Personnel in three units of the county's Municipal Services Agency -- the departments of Transportation, Water Resources and Water Quality -- use SEROW to enter information on upcoming projects. That includes the location of a project, its start and end dates, and contact details for the person responsible for the project. When a department contemplates a new project, a manager can query the system to see what other activity is scheduled for the same area, viewing the results on the map display.

"It helps identify any projects you would be overlapping if you're trying to speculate visually," said Tony Henderson, Sacramento County's senior software engineer.

Individual users with administrative privileges can go into the application, enter the specifications for a new project, visually identify what other projects might be in that immediate area and enter their contact information, said Cynde Porter, an IT analyst with Sacramento County GIS. "Then the application will go in and see if there's any potential for collaboration," Porter said. In addition to informing the person who enters the new project, the system sends an automated e-mail notification to anyone in charge of another project in the affected area.

If one department intends to excavate a street in March, and a second one plans to excavate the same street in April, the system makes sure officials in each department know about the other's project. They can then modify their schedules to do the work at the same time. "If an overlay [a repaving project] is going to occur six months from now and somebody has a project to do an excavation eight months from now, they might push up their schedules to have the excavation happen before the overlay," Henderson said.

The county Department of Transportation's Right-of-Way Management Section uses SEROW constantly throughout the day, said Gary Kodani, a senior civil engineer. Kodani and his colleagues are responsible for approving encroachment permits, which government departments and outside entities, such as utilities, must acquire to excavate in the county's right of way. The department uses SEROW to make sure streets aren't excavated twice, and if an organization needs to dig up a street that was paved fewer than three years ago, contractors are held to the highest repaving standards.

Although SEROW offers definite benefits, it's not perfect, Kodani said. Aside from occasional periods when the software becomes unavailable, his biggest complaint stems from the fact that information in the database isn't always accurate. "Your data is only as good as what you put into it," he said. "A lot of people who contribute to the data pool sometimes are not diligent about keeping it up."

Worth the Effort
Convincing individuals that keeping SEROW up to date is worth the extra effort it takes to enter the data was the biggest challenge faced in implementing the system, said Earle. "I think it's proved it can help, in retrospect. But it was a tough sales job."

One way SEROW has paid off is in money the county saves on repaving. In 2003, Sacramento County reported that it cost $10,000 to have an associate-level engineer maintain all projects within the SEROW database for one year. But preventing just one unnecessary resurfacing of a cul-de-sac saved county taxpayers $20,000. More recent figures aren't available, Porter said.

Without SEROW, the Right-of-Way Management Section probably wouldn't address likely conflicts among excavation projects, Kodani said. "Which means that we would have more instances where we would be digging up newly installed streets."

Although it won't happen for a few years, county officials hope to make SEROW available on the public Internet, with appropriate security controls. That would allow other governments in the region, as well as private-sector entities -- such as utilities and real-estate developers -- to coordinate with the county on excavation projects. It could also help when the county needs to work on facilities it owns, such as the sewer network, that occupy rights of way controlled by other jurisdictions. "It would be great to coordinate with a city like Elk Grove to let them know, 'We're planning a project in your right of way on such-and-such dates. Do you have any sort of activity going on?'" said Mark Dumford, Sacramento County's GIS manager.

The county would also like to include other entities, Porter said, "Like cable companies, [Pacific Gas & Electric] and utility districts that might be trenching in the same area county departments might be working in."

It would also be useful to expand the application so an organization can use it to consider not only who else plans to excavate a certain street, but also how that project will affect activities in the broader area, Henderson said. For example, it might be necessary to consider how the project will affect school bus routes.

Furthermore, the system could be broadened to include data beyond street excavation.

"Streets are probably the most predominant request for an application of that nature," Henderson said, "but it could be applied, really, to anything."
Merrill Douglas Contributing Writer
Platforms & Programs