Street Construction Approach
The City of Alamosa has more than fifty-seven miles of street to maintain throughout the City. In the past, resources for street repair have ebbed and flowed with each budget year. This led to a backlog of streets in need of significant repair. Since 2008, the City has adopted a new method of budgeting for street repair and maintenance. By using long-range financial planning, the City has set aside significant dollars for street work in recent budgets and will continue to do so for the foreseeable future. By identifying a steady stream of funding, the City is able to plan repairs into the future. While a significant downturn in our local economy could require changes to the plan, Street repair is a top priority of City Council. A typical road in the City of Alamosa includes six or more inches of road base (small stones and dirt compacted to form the foundation of the street) and three inches of asphalt. A major road like state will be heavier built than a standard residential street the concept is the same. When repairing streets there are several types of repairs we typically see.
Plant mix seal coat, slurry seal, and crack sealing: The City can apply a plant mix seal coat (Murphy from first to Clark had this treatment applied). This is a process to protect and level the pavement that involves covering the street with an oil and stone mix. It does not improve the load bearing capacity of the street very much. Additionally, the City spends resources on crack sealing. Crack sealing slows pavement deterioration by filling cracks to keeps water out. A slurry seal a thick coating of oil and fine material, can be used (and was done on a portion of Tremont nearest 285) to further extend the life of the road. It does so by sealing the finer cracks and protecting the base asphalt from the effects of the sun and weather. The above treatments are generally done on roads that are in “good” condition and whose base is still in good condition. It can also be used on low traffic streets. they are the less expensive approaches to street repair and can allow the City to cover more area with the same amount of money.
Mill and Overlay – This involves “milling” or grinding a few inches off the top of the road and overlaying the road with new asphalt. This was done by CDOT on Main Street and most recently on a portion of State Street from 6th to just past 4th street. This is used for streets that need more reconditioning than can be provided by the plant mix seal coat. This is more expensive than the seal coats, but provides for a quality repair that should last for many years.
Full reconstruction – This is by far the most expensive road repairs the City undertakes. This is used for roads whose bases are in poor shape and must be rebuilt from the ground up. Most recently this was done on State Street from 3rd to 1st Street. A street that falls into this category has deteriorated to the point that repairing the road is not viable, it must be rebuilt. Because this is the most expensive repair, the City can only do short sections of road way each year.
With so many streets and options on what to do, how does the City select which streets are repaired and in what order? We use a systematic approach with the following guiding principles:
- Maximize street miles repaired – focus our efforts to cover as many streets as possible. This principle has us focus more resources to seal coats and less to reconstruction. Very rarely will the City focus solely on reconstruction alone.
- Busiest streets first – City staff is in the process of updating daily traffic counts on all City streets. The busiest streets such as State Street will receive focus as they are key travel ways in the community. The relocation of the elementary schools will have an impact on the flow of traffic as well.
- Don’t let good streets become bad – while someone may wonder why a street that looks to be in better shape than another has work done first, it is an effort to avoid more costly repairs later. A lower cost maintenance treatment like a seal coat may keep a street from falling toward the more costly reconstruction.
- Coordinate with other utility work – nothing is more aggravating then watching a brand new street get cut up to replace or repair a utility. The City does its best to anticipate issues within its utilities, and tries to get others such as the phone and cable companies to also cooperate.
- Equitable distribution around the community – The City can’t focus on one part of town for any length of time without being in danger of other areas falling towards reconstruction.
How do we do all of this? The City inspects 35% of the streets each year and uses software to track and identify streets in need of repair and the type of repair necessary. Notes on conditions such as cracking width of cracks, settling, “alligator cracking,” and other items are recorded. Some indicate problems in the asphalt and others a more serious problem with the base of the road. The streets are graded from good (new part of State Street) to fail (Hunt Street by the post office). If you have questions please contact public works for more information.
The following streets are scheduled for repair over the next five years:
2011 – 4th State to Ross; State, 1st to Bridge; Ross, Main to 6th; Market, Main to Thomas
2012 – 4th, Denver to State; Third, Hunt to State; Hunt, 3rd to 4th; State, 14th to 17th.
2013 – San Juan, 8th to 14th; Brown, Sunset to Clark; State, 17th to Airport; Franklin, Stadium to Murphy
2014 – West 8th, West Ave to Washington.
2015 – 2nd, State to Ross; 2nd, La Veta to Richardson; Richardson, 2nd to Main