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is
routine work performed to keep the pavement in a
condition as close as possible to its newly constructed
condition. This results in a cost effective use of
limited available funds, and provides maximum benefit
to the traveling public by enhancing safety of the
roadway and improving ride comfort of the road surface. Street
maintenance can be divided into three strategies:
maintenance, resurfacing and transition.
are done
in preparation for upcoming scheduled resurfacing
and include the types of repairs listed below.
Crack Sealing:
- Cracks are filled with hot applied rubberized
material to prevent water infiltration into the
road base. This repair may take place one to two
years in advance of the scheduled resurfacing.
Rideability Pass:
- Newly paved areas that improve the smoothness
of the travel lanes but do not cover the entire
roadway.
Crown Pass:
- Newly paved areas down the center of the roadway.
This strategy is used to develop adequate cross
slope on flat roadways to allow water to drain
to the sides.
Base Repair:
- Removal of any distressed areas where the pavement
is fractured and broken and is allowing water to
weaken the subgrade under the roadway. Various
methods are used to remove the distressed asphalt,
such as backhoe and cold mill planers. Once removed
new asphalt is placed. These repairs are accomplished
prior to the scheduled resurfacing sometimes up
to a year in advance.
Tree root removal:
- Removal of raised areas
in the pavement caused by tree roots. Either the
areas are completely removed and replaced or ground
down and patched. These repairs take place up to
a year in advance of resurfacing.
Skin patching:
- Low areas that are imperfections in the asphalt
are patched with fine AC (asphalt concrete). Typically
these depressions are small and have settled over
time. This gives the street a patchwork appearance.
These repairs are done during the warmer weather
sometimes a year in advance but usually just prior
to resurfacing.
include the techniques that are listed below. The appropriate resurfacing treatment for a roadway depends on the existing pavement condition. It is more cost effective to resurface a street before pavement deterioration becomes severe, requiring reconstruction.
Slurry Seal:
- A blend of oil and small aggregate that is applied to the streets. Slurry seal is a preventative maintenance procedure. The construction cost is approximately $1.20 per square yard. Slurry sealing can extend the life of a street by 5-7 years.
Microsurface:
- A thin surfacing containing polymer modified emulsion and graded aggregate. Can be used for the same applications as slurry seals, but thicker layers can be placed allowing for slight rut filling. Construction cost is approximately $3.50 per square yard. Microsurfacing can extend the life of the street by 7-10 years.
Chip Seal:
- Application of liquid asphalt followed by placement of small rock chips on the existing pavement. This treatment adds strength to the existing pavement and can extend the life of the street by 8-10 years. Chip Seals are no longer used alone in the City of Sacramento.
Cape Seal:
- A chip seal followed by a slurry seal. This process gives the strength of a chip seal with the added benefit of a smoother riding surface; therefore it is used instead of a chip seal. Construction cost is approximately $3.50 per square yard. Cape sealing can extend the life of a street by 9-12 years.
Asphalt Rubber Cape Seal: (ARC)
- Same as cape seal but contains asphalt rubber, which can be used over cracked pavements and is resistant to reflective cracking. The Asphalt rubber is a blend of asphalt cement, reclaimed tire rubber, and additives. Construction cost is approximately $6.00 per square yard. Rubber Cape sealing can extend the life of a street by 10-14 years.
Overlay:
- The highest form of street maintenance, overlay involves the placement of a new layer of asphalt, approximately one and a half to three and a half inches thick, on the street. The construction cost to overlay a street is approximately $18 per square yard depending upon the thickness required. Properly maintained, an overlay can extend the life of the street by 20-25 years although heavily used streets may require more frequent overlays.
Rubber Overlay:
- The same as Overlay but contains asphalt rubber. The Asphalt rubber is a blend of asphalt cement, reclaimed tire rubber, and additives. The construction cost to rubber overlay a street is approximately $27 per square yard depending upon the thickness required. Properly maintained, a rubber overlay can extend the life of the street by 20-25 years and improves resistance to rutting and fatigue as well as reducing traffic noise and providing the ecological benefit of using waste tires that would have ended up in the landfill.
Transition Strategy
Street Services has developed transition strategies
to address the significant backlog of street segments
identified for reconstruction. Improving the roadway
condition of these streets makes it cost effective
to apply one of our standard resurfacing strategies.
This transition strategy was used extensively in
the downtown area in 2002 and 2003.
What to expect / helpful tips
Convenience
for businesses and residents is a top priority during
the street resurfacing process. Because advance warning
of roadwork is crucial, the City wants you to be
ready. You'll be notified with a reminder hanging
on your door three to five days before your street
is resurfaced. This notice will contain information
about when the roadwork will occur. Note, before
and after the actual resurfacing, work crews may
be seen performing other work on the street.
Street
resurfacing typically occurs in the summer and
fall. Although the roadwork is scheduled around commute
hours, the details of what to expect are different
for each type of resurfacing. Most commonly, no
vehicles will be allowed on the street during the
resurfacing process and the street will be closed
for a portion of the day. Depending on the condition
of the street, one of three types of resurfacing
will be applied on the street.
Project List Development
The City performs an inventory of approximately one third of its residential and collector roadways on a rotational basis each year, along with all of the arterial and collector streets. Thirteen different distress and roughness data are collected. Each distress is measured with three severity levels and five density levels. The roughness is collected using five levels. Other information included: age, location, maintenance history of the roadway, council district, curb shoulder and pavement types and street functional classifications.
The needs list is developed using data in the City's ITX/Stanely SuperPMA (Pavement Management Application) computer program. The analytical routines unique to the SuperPMA allow the City to better assess the whole street network objectively and to develop a rehabilitation program that maintains every street at the most cost-effective point.
Street Services is continuing to develop a ten-year rehabilitation cycle that will include every street in the City of Sacramento. We currently have a ten-year street maintenance plan that addresses much of our approximately 2.6 million square yards of paved roadway annually. However there are areas of the City not included in this plan where maintenance was deferred for several years because of conflicts with other projects or just lack of funds. More costly maintenance strategies are now required to actually move these streets from a backlog status into the ten-year cycle. The annual cost today for delivering a ten-year street maintenance plan, without addressing these backlog streets, is approximately $12 million.
Our annual street resurfacing program is currently funded through Measure A and gas tax dollars and AB2928. Additional fund sources need to be identified.
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