A consultant that ranked the condition of the 302 miles of Sandy Springs streets said the city needs to spend $5.2 million to keep them in good or satisfactory condition.
At a June 15 meeting, Trevor Triffo of MDS Technologies presented City Council with a State of the Road Network 2020 report that ranked every section of road in a Pavement Condition Index on a scale ranging from extensive damage to like new. The survey revealed almost 72% of the city streets are in good or satisfactory condition, the top two rankings. Just under 10% are in poor or lower condition.
The city uses the report to determine what roads to put on its paving budget, Public Works Director Marty Martin said.
When a road falls below 60 on the Pavement Condition Index, it becomes a candidate for rehabilitation through milling and inlaying of asphalt mix. When the road gets down to the 15 or 20 range, Triffo said it becomes a candidate for reconstruction.
He suggested that the city start scheduling preventative maintenance including applying seals on roads in good condition to extend how long they stay in that condition. Surface treatments or relatively low-cost maintenance activities early in a road’s life might cost $4 to $8 per square yard.
But if the road is allowed to deteriorate to where it requires reconstruction, maintenance costs might be $45 to $75 per square yard, which is 10 times as expensive.
“It makes sense, ideally, to spend the money on a road that’s higher up on the performance curve,” Triffo said.
The city mainly does mill and overlay work. He said the city should look to begin preventative maintenance surface treatment options in the next three years or so. That should result in savings for the city on its annual road maintenance budget.
Martin told council and Mayor Rusty Paul that the city has had mixed results in the preventative maintenance methods it has tried. He wants to try the methods MDS Technologies suggested to see how they work.
The survey evaluated distress to the roads by type, severity and extent to come up with the rankings using a standard created by the American Society of Testing and Materials that he said is used by hundreds of different municipalities and counties around the country and the world. Triffo advised the city to stick with the same testing standard so that the city can track trends.
An example of a road in serious condition, which ranks just above failed, was given as Northridge Parkway between Roswell Road and Dunwoody Place. Its pavement condition index rating was 23.
Triffo told Councilmember John Paulson that the difference in ratings given by MDS Technologies and the city’s previous consultant are due in part because that consultant used ride quality measurements mixed in with road condition data.
Martin told Councilman Tibby DeJulio that curb and gutter conditions were not part of this road survey. The Public Works Department does an assessment as paving projects become active.
“If we see deficiencies in the roadway at the time we’re there, we take those measures at that point in terms of sagging gutter, whatever the case is,” Martin said.
Repairs and replacements to storm drainage and catch basins are made in advance of the actual paving projects.