There’s a bumpy road ahead for city street maintenance.

The 375 miles of street pavement in Thousand Oaks is valued at $700 million—an enormous investment that must be maintained, said Mark Watkins, director of public works.

To give a better idea of the value of the city’s street pavement, Watkins compared it to other city assets, such as the Civic Arts Plaza at $75 million and the Hill Canyon Wastewater Treatment Plant at more than $100 million.

Thousand Oaks implemented a pavement management program in 1991 to protect its investment. The city hires consultants every five years to collect data on the condition of the streets and create a five-year strategy for street rehabilitation projects.

Another municipality might wait until a resident calls and tells where a pothole is—after it’s knocked off the hubcap of the resident’s car.

But Thousand Oaks is more proactive and high-tech. In fact, the most recent consultant went to work in January using a van with GPS, measuring devices, lasers and computers.

The consultant, kind of a fortuneteller who predicts when roads will need repairs, measured road roughness, rut depth, surface texture, cracks and other defects. The size of the street as well as traffic was included in the study, with digital photos and an inventory of more than 25,000 street signs.

Using the data collected, the program then calculates street pavement condition, expressed as a Pavement Condition Index score from 10 to 100, with 100 being best.

Overall, the condition of the city’s street pavement is very good, with an average rating of 81. But residents shouldn’t get too comfortable: Due to a decrease in street maintenance funding and an increase in pavement costs, city staff expects the street rating to fall to 79.

The statewide average is 68, projected to fall to 58 in 10 years if current maintenance funding levels continue, according to a 2009 California League of Cities report.

The city consultant’s report said 84 percent of the city’s streets are rated above 70, which is considered in good or better condition. Eleven percent of the streets are in the 60 to 69 range––in need of repair to avoid more costly reconstruction in future years.

  “One dollar spent now on the rehabilitation of these streets saves $7 to $8 in future reconstruction costs,” Watkins said.

Five percent of the city’s streets are past simple rehabilitation and need expensive reconstruction.

Those streets, rated in the 10 to 59 range, include Lawrence Drive and the Norwegian Grade section of Moorpark Road.

Lone Oak Drive is another street with a low rating, but repairs will be postponed until a water reservoir replacement project is completed in the next two years, Watkins said.