Some 21.5 miles of neighborhood streets in North Manteca will receive maintenance work this summer under a plan before the City Council tonight.

The road work is for the area bounded by Union Road on the west, Main Street on the east, Northgate Drive on the north, and Louise Avenue on the south as well as an area bounded by the Tidewater Bikeway on the west, Main Street on the east, Northgate Drive on the south, and Lathrop Road on the north.

It will cost $500,000 to place slurry seal on 20 lane miles of streets and overlay 1.5 miles of streets. Pavement in the worst condition will receive an asphalt overlay.

A survey of city streets in 2009 shows that the 191 total centerline miles of municipal roadways have a pavement condition index of 75.  That means, on average, they’ve got 75 percent of their life expectancy left. That compares to the Bay Area average of 70 percent. Manteca’s better position has a lot to do with the fact most roads here are newer.

The 191-centerline miles include 32 miles of arterials, 26 miles of collectors, and 133 miles of collector streets.

Manteca is now spending an average of $500,000 a year on road maintenance projects. But the pavement management study in 2009 showed that amount needs to be kicked up to $1.3 million annually each year through 2012 just to maintain the current level of quality. Since the city hasn’t been able to do that because of financial constraints, it means Manteca has fallen behind roughly $2.4 million in needed road work.

The 2009 study showed that the existing 191 miles of Manteca roads have a replacement value of $79.8 million. That reflects a 53 mile increase in 10 years.

Public Works Director Mark Houghton in the past has noted that there is a misconception that higher gas prices means more gas taxes are rolling into cities and the state for road maintenance. Nothing is farther from the truth.

The gas tax is stagnant. On top of that, the state has been raiding it regularly to try and balance state budgets.

The result is that for actual significant pavement beyond work covering the basic cost of crews and materials to do routine street maintenance gas tax accounts for only a 20th of what is actually spent for work on existing roads in Manteca during the past 10 years.

Gas tax is used by cities to cover the ongoing cost of crews plus performing work such as filling in potholes. For long-range maintenance, gas tax accounted for $269,907 of the tab during the past decade. Measure K — the half-cent sales tax put in place by San Joaquin County voters for transportation needs — led the way with $2,046,642. The rest came from five other sources.