If done correctly, maintaining the roads of a town is a lot like having Dr. Hawkeye Pierce run the triage area outside the hospital tent on the TV show “M*A*S*H”.
After looking over all the options for what to do with South 8th Street, the Pagosa Springs Town Council decided at last week’s meeting to wait until 2015 to begin working on the project.
As Mike Davis from Davis Engineering stepped up to the microphone from the audience gallery and prepared to explain to the council all its options, Interim Town Manager Greg Schulte went over some of the history of the project.
Last year, the council discussed a repaving project for 8th Street, but because of all the bus traffic from the high school and elementary school, it was decided the intersection with Piedra Street needed to be concrete, similar to the Apache Street intersection.
When a vehicle approaches an intersection, the driver hits the brakes and decelerates, causing extra wear and tear on the pavement. The same thing happens as the vehicle accelerates through the intersection. Replacing the asphalt with concrete in these areas makes the surface stronger and extends the life of the pavement.
Because of the added expense of concrete, town council only paved 8th Street from Apache Street to the Pagosa Springs High School property line in 2013 and saved the rest of the 8th Street repaving project until this year.
During the design stage of the Piedra Street intersection, town staff hired Western Technologies to do a geotechnical analysis of the base underneath the roadway. After a number of bore samples were conducted, it was discovered there was only between 5 and 8 inches of base instead of 12 to 15, as previously thought.
In other words, a simple repaving project is no longer the best option.
“Originally it was considered for a repaving,” Davis began, “which would correlate with options one and two that I provided in the estimate here.” Davis referred to the handout he had just given the councilors.
Davis explained that simply removing and repaving the top 4 inches of asphalt would cost the town $467,000. This would include reshaping and re-compacting the base layer. To do the same thing with 5 inches of asphalt would cost $535,000.
“The problem with that,” Davis explained, “is those repaving jobs don’t correlate to what is typically called for in a twenty-year design. Generally, if you are pursuing a construction job of this type, you want it to last twenty years.”
Davis went on to explain how traffic counts are used to calculate the amount of wear and tear a paving project will experience.
“They do what is called an equivalent single-axle load calculation,” Davis said, “where they are basically converting everything to an eighteen thousand pound, single–axle truckload, and that’s how they determine what your structure should be to last for twenty years.”
Using the Colorado Department of Transportation’s traffic data from 2007, Davis calculated a 3-percent growth in traffic per year based on how much more traffic the street sees today, and extrapolated for the next 20 years. Added to the geotechnical information from Western Technologies, it was determined a simple repaving project as described in option one and two would not last.
“They came back with recommended structural sections for the road to meet that twenty-year design,” Davis explained. “Well, the repaving option didn’t even come close. I don’t know how many years it would mathematically work out to as far as the design height, but it might be five years. It might be seven years.”
Davis explained that the minimum design requirement to reach a twenty-year lifespan would be 5 inches of asphalt on top of 9 inches of gravel on top of a re-compacted subgrade. He also explained that the use of a geo grid material would allow them to use a thinner gravel layer.
“It turned out the most economical structural section,” Davis said, “ended up being four inches of asphalt over seven inches of gravel over geo grid over eight inches of re-compacted subgrade, which is option number three on your spreadsheet there, or in round numbers $838,000 for a reconstruction project.”
Davis pointed out that if the concrete reinforced intersection at Piedra Street were changed back to asphalt the town could save $160,000.
He went on to clarify that the dollar amount for each option presented to town council included from the edge of the concrete at the South San Juan Alley to the edge of the concrete on the north side of the Apache Street intersection.
He also explained that the traffic calculations included not only school buses, but also the trash trucks headed to the landfill and the construction trucks headed to the sewer lagoon facility.
All of the dirt from the Wal-Mart excavation project on the corner of Alpha Drive and Aspen Village Drive on the west side of town is being hauled downtown and dumped at the town yard south of Yamaguchi Park, presumably to be used when the sewer lagoons are decommissioned and reclaimed. Davis estimated there are currently an additional 80 trucks per day using 8th Street.
Schulte then reminded town council that the 2014 budget allocated $450,000 for the 8th Street repaving project, or about half of what would be required to do the job right. One option would be to spend money out of the town’s capital reserves. Another option would be to use impact fees.
As a side note, on June 6, Wal-Mart pulled its building permit and paid $494,186 for its impact fees. At the time, Town Planner James Dickhoff explained to SUN staff, “There are very specific items we can use that for, and we have to justify that anything we spend that money on is to mitigate and accommodate the particular development we collected the fees for.”
In the case of Wal-Mart, $409,000 was collected to offset possible road improvements, $15,000 was for regional public buildings, and $69,000 went to emergency services providers.
Another option Mayor Don Volger asked about at last week’s meeting was doing the 8th Street reconstruction project in phases, and Schulte confirmed the town has enough money budgeted to do up to and including the concrete intersection at Piedra Street. Later in the discussion, Dickhoff pointed out that doing any project in phases bumps up the overall price because it costs extra to restage.
When council member David Schanzenbaker asked how bad the roadway is right now, Davis answered, “The street has obviously failed in several areas. It’s rutted and showing alligator cracks in spots, so it’s to the point where the cost of trying to maintain an impervious surface with crack sealing or whatever, it’s just not worth it to spend the money. You’re better off just letting it fall apart because you know you’re going to replace it.”
“So maybe you could remind me and the rest of council,” Schanzenbaker pressed, “when we had an engineering firm come in and do a capital improvement needs assessment survey in 2009, they recommended when you have something that needs full reconstruction, you de-prioritize it and you spend your money on streets that aren’t in as bad a shape.”
“That’s true as far as maintenance is concerned, yes,” Davis responded, “Those are two different animals. You have maintenance and you have reconstruction.
Obviously, if you have one of your major streets in town that’s totally cratered with potholes or whatever, you’re going to start getting a lot of complaints, so as far as how you prioritize maintenance versus reconstruction, that’s a process the town has to go through.
“As far as maintenance, yes, you want to take care of the good asphalt first, and if something has already failed, then it moves over to the next stack, which is reconstruction.”
One councilor pointed out that if the whole thing needs to be torn up and redesigned anyway, the town should conduct a series of public input meetings and look at all options, including sidewalks, landscaping, bulb-outs at the intersections, raised crosswalks, and so on, similar to what was done recently with Lewis Street.
And so the discussion continued for another 30 minutes, debating the pros and cons of various street features, but, in the end, it was decided the 8th Street reconstruction project should be tabled until 2015 so the council can re-examine the budget and figure out the best strategy for completion.
