County of San Luis Obispo
County of San Luis Obispo July 2008 Pavement Report
Department of Public Works and Transportation
San Luis Obispo County Road System
Board of Supervisors District 1, Harry Ovitt District 2, Bruce Gibson District 3, Jerry Lenthall District 4, Khatchik “Katcho” Achadjian District 5, Jim Patterson
Prepared by
Department of Public Works Paavo Ogren, Director Glen Priddy, Deputy Director Operations Dave Flynn, Deputy Director Administration Jim Berg, Roads Analyst
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Table of Contents Page 1. Introduction .....................................................................................................5 1.1 Pavement Management.....................................................................5 1.2 Routine Maintenance Activities......................................................5 1.3 Pavement Preventative Maintenance Program ............................5 1.4 Current Conditions........................................................................ 6-7 3. Revenue.............................................................................................................8 3. Expenditures ....................................................................................................9 3.1 Revenues vs. Expenditures ..............................................................9 3.2 Maintenance Operating Costs ................................................. 10-11 3.3 Road System Capital Outlay Projects .................................... 11-13 4. Preventative Maintenance..................................................................... 13-15 5. SLO County Road Maintenance Strategy .................................................16 5.1 Road Maintenance Repair Strategy........................................ 16-18 5.2 MicroPAVER............................................................................... 20-22 5.3 Maintenance program results and budgets .......................... 22-24 6. Conclusion.......................................................................................................24 Bibliography .......................................................................................................25 Appendices..........................................................................................................26 Appendix A – Indirect Road Costs .............................................. 27-31 Appendix B– Pavement Distresses ............................................... 32-33 Appendix C –Five Year Listing of Planned Overlay Projects ........................................................ 34-40 Appendix D – Complete listing of all San Luis Obispo County roads with pavement condition rating.................. 41-95
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1 Introduction County Government is responsible for providing a safe and healthy environment for its citizens. Toward that end the Department of Public Works is tasked with maintaining the County road system infrastructure and associated structures, in the County of San Luis Obispo. Road system structures include: • 1315 miles of roads, comprised of; o 1084 miles of paved roads o 231 miles of gravel roads • 207 Bridges • 4,300 road drainage culverts • 47 Flood Control Basins for roadside drainage. • 12,200 Road signs • Traffic signals at 17 locations around the County • 102 miles of Sidewalks • 1220 Sidewalk ADA ramps
1.1
Pavement Management
The primary investment in the county road system is in paved road surface. Since 1997, the Public Works Department has maintained a formal pavement management system for documenting road conditions and forecasting needed improves and funds for the system. It is utilized to manage pavement conditions so the system does not deteriorate below acceptable standards. The Department maintains the roads using a field staff of 75 employees to perform routine maintenance duties. Routine maintenance involves roadway patching, shoulder maintenance, signs and striping, mowing and tree trimming, culvert repair/replacement, bridge maintenance, and correction of right of way drainage issues and other activities.
1.2 • • • •
Routine Maintenance Activities Repair deficiencies in the road system, clearing slides, repairing washouts, etc. Tasks which help prevent further deterioration of the road system, such as crack sealing and patching. Proactive preventative maintenance tasks, such as scheduled culvert cleaning to prevent greater damage at a later date. Tree and brush removal to improve public safety or prevent greater damage from falling trees.
These activities, while critical to safe operations for the public, do little to extend the life of the infrastructure.
1.3
Pavement Preventative Maintenance Program
In conjunction with the routine maintenance work the road system requires regular preventative maintenance on all roads to achieve the greatest cost/benefit ratio. On non-paved roads this means routine grading and graveling and shoulder maintenance. On paved roads maximum life is realized with a formal pavement management program. Pavement preventative maintenance activities are tasks such as; seal coat, chip seal and pavement overlay.
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Current Pavement Conditions In February of 2008 an annual survey of 25% of County paved roads was completed. This survey results in a Pavement Condition Index rating being assigned to each section of paved road surveyed. Pavement Condition Index or PCI is a scale of 0-100 that rates the condition of pavement with a value of less than 10 being failed pavement and 100 being perfect pavement. Using this rating scale the overall condition for all paved county roads in May 2008 was 63.1. The following data and tables are based on pavement condition resulting from that pavement condition survey.
Pavement Conditions 2008 Road Classification
PCI for Class
Road Miles
% of Total
Bad 0-20
Poor 21-40
Fair 41-60
Good 61-80
Best 81-100
Miles
%
Miles
%
Miles
%
Miles
%
Miles
%
Arterials
73
104
10%
0.35
0%
5
6%
11
17%
38
31%
49
45%
Collectors
63.3
420
39%
11.58
3%
49
13%
96
29%
121
25%
143
30%
Local Roads
60.5
560
52%
15.11
3%
76
16%
114
30%
196
30%
159
22%
Total County
63.1
1,084
100%
33
3%
141
13%
303
28%
303
28%
303
28%
Conditions by Road Classification. Table 2-1
Pavement Condition Areas in SLO County. Fig 2-1* *Pavement Condition Areas are selected to group similar environmental and traffic impact on pavements and differ from Road Maintenance Sections.
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REGION
Average PCI February 2008
Area 1
59.4
Area 3 Area 4
65.2 67.5
PCI by Region. Table 2-2
Pavement Rating by Community Community
Average PCI Feb. 2008
Avila Beach
84.3
Cambria
66.4
Cayucos
72.9
Los Osos
64.3
Nipomo
67
Oceano
65.4
San Miguel
52.9
Santa Margarita
42.7
Shandon
46.8
Templeton
69
PCI by Community. Table 2-3
Miles of Paved Road by PCI Category PAVEMENT CONDITION Road Miles 2006 Road Miles 2007 Road Miles 2008
Bad 0-20 11 14 33
Poor 21-40 67 138 150
Fair 41-60 344 255 239
Good 61-80 365 365 343
Best 81100 334 304 320
Avg.* PCI 68.0 68.9 67.6
Deferred Maintenance (2007 dollars) $62,000,000 $84,125,593 $103,652,569**
Road conditions for last three years. Table 2-4 *note: this PCI is the rating at the time of inspection, other charts may show the PCI at the time work is applied. **2008 increase in costs reflects an adjustment to the construction cost tables from previous years to account for increased construction costs.
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2.
Revenue
The County road system is supported by revenue from a number of sources. Because funding generally fluctuates with economic changes maintenance cost must be constantly monitored and adjusted to match income. Since voters approved Proposition 42 in 2004, the County has received revenue from the sales tax on motor fuel. While the funds have been divided among various transportation needs by the legislature, we expect $3.6 million annually which provides the basis for preventative maintenance work.
Roads Major Revenues And Expenditures $18,000,000
$16,000,000
$14,000,000
$12,000,000
$10,000,000
$8,000,000
$6,000,000
$4,000,000
$2,000,000
$0 03/04 Property Tax
04/05 ISTEA
05/06 Prop 42
06/07 General Fund
07/08 TDA
Gas Tax
08/09 Maintenance
Road revenue sources compared to Maintenance costs. Table 2-1
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3.
Expenditures
When road revenues are the same or reduced, maintenance work must be cut back with the potential for disastrous and costly results. As the cost of “routine” maintenance increases less money is left for preventative maintenance. Routine maintenance costs rise due to the cost of complying with unfunded mandates, (such as stricter environmental compliance), increased material and labor costs and rising equipment costs.
3.1
Expenditure distribution
R o a d F u n d s B u d g e t e d E x p e n d i t u r e s fo r F Y 2 0 0 8 /2 0 0 9 M a jo r C o n s tr u c tio n P r o je c ts , $ 1 2 ,8 6 0 ,0 0 0
M a in te n a n c e , $ 1 2 ,4 4 5 ,0 0 0
Pa v e m e n t O v e r la y , $ 6 ,4 9 4 ,0 0 0
U n d is tr ib u te d E n g in e e r in g , $ 4 ,0 3 0 ,0 0 0
Road Fund Expenditures Table 3-1
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3.2
Maintenance Operating Costs
County Tree Crew Dealing with fallen trees. Fig. 3-1
Routine Maintenance Cost Distribution for San Luis Obispo County in 2007
S ig n s , S tr ip in g & M a r k in g s 4% R o a d D r a in a g e 8%
A ll O th e r R o a d W o rk* 9%
P o th o le p a tc h in g 8%
A d m in is tr a tio n 4% M a jo r R o a d R e p a ir 23% M a te r ia ls $ E q u ip . H a n d lin g 2%
G r a v e l R d . M a in t. 7% T r e e T r im m in g & Remov al 16% R o a d s id e M o w in g 2%
S h o u ld e r M a in t. 14%
B r id g e R e p a ir /M a in t. 2%
S to r m D a m a g e 1%
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Maintenance Costs. Table 3-2
Routine Maintenance costs 2007 Pothole patching Administration Major Road Repair (1) Materials & Equip. Handling Bridge Repair/Maint. Shoulder Maint. Storm Damage Roadside Mowing Tree Trimming & Removal Gravel Rd. Maint. Road Drainage Signs, Striping & Markings All Other Road Work (2) Total in 2007
$ $ $ $ $ $ $ $ $ $ $ $ $
248,379 715,111 279,765 1,702,682 763,474 138,779 521,161 601,871 511,156 210,213 439,422 309,368 1,662,942
$
8,104,324
Table 3-3 (1) Major Road repair is less the cost of repairs included in capital projects such as overlay preparation. (2) other work includes; drainage channels, sidewalks, gravel pit reclamation, and guardrail work.
The maintenance costs shown in table 3-2 are operating costs and do not include capital projects such as pavement overlays or bridge reconstruction. Road crews are increasingly tasked with maintenance of structures not directly tied to road maintenance. Some of these tasks include: • Storm water basins, road culvert and channel maintenance o The Federally mandated NPDES program requires a large commitment of time and materials by road crews to assure compliance with storm water runoff rules. o More basins and channels to contain storm water are required and must be maintained. o Down drain inlets and associated storm water filters must be cleaned regularly. • Environmental restoration o Extra care must be taken to assure minimum environmental damage from road work o Roadside repair work must be carefully restored in environmentally sensitive areas. • Sidewalk repair o More residential streets now include sidewalks o Sidewalks installed years ago are now reaching the point where the require repair or reconstruction o Recent court rulings have forced the county to maintain a higher standard for sidewalk pavement • ADA ramps and facility maintenance o Federally mandated ADA compliance now requires curb ramps for all sidewalks o Older ADA ramps may not comply with current rules and are aging to
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•
3.3
where they require replacement Roadside Bike lane sweeping and maintenance o As population increases and more people bike along roadsides crews must increase the level of maintenance o The addition of bike lanes requires sweeping of road shoulders that previously needed little attention
Road System Capital Outlay Projects
Widening of Vinyard Drive bridge. Fig. 3.2 In 2007 approximately 40 miles of roads have been overlaid to date in San Luis Obispo County with a 2 ½” – 4” asphalt overlay. Due to the tremendous rise in the cost of asphaltic oil, gravel aggregate and labor costs, paving prices have increased exponentially from the 1990’s. In 2007 the average cost per mile for overlaying county roads was $245,000 per mile for the average 26.6 foot wide county road. The cost breakdown for paving in 2007 is as shown:
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A / C O v e r la y C o s t 2 0 0 7
P e r m it s , $ 1 4 3 . 0 0
D e s ig n , $ 1 1 ,1 7 8 .0 0
P r e . E n g in e e r in g , $ 5 ,2 7 6 .0 0
C o n s t r u c t io n , $ 8 ,3 2 2 ,2 4 1 .0 0
•
•
4.
M a in t e n a n c e C r e w Pr e p ., $ 1 ,4 7 9 ,5 1 2 .0 0 C o n tr a c t P r o c e s s in g , $ 5 ,2 9 5 .0 0 U t ilit y C o o r d in a t io n , $ 8 6 0 .0 0
The table in appendix C is a listing of roads scheduled for pavement overlay. It should be understood that this list of roads requiring work is subject to the discretion of the Road Maintenance Division Manager. There may be considerations beyond the scope of the pavement management system that determine the priority of overlay projects or chip seal treatments. There are no scheduled roads for chipseal coating at this time.
Preventative Maintenance Why do Preventative Maintenance?
Preventive maintenance is a way of managing investment dollars in the infrastructure to maximize the cost/benefit or rate of return. This strategy is a systematic method of performing road repairs and rehabilitation based on a logical and predictive program rather than fixing problems as they arise. When it comes to roads, people tend to think locally not globally. It is the pothole at the end of the driveway, the rough pavement near the school and the ruts in the nearby intersection that they are concerned about and that puts municipal engineers on the spot. Routine maintenance must deal with these local near term local issues. Preventative maintenance needs to assure a strong, long term, investment foundation. Preventive maintenance is all about fixing small problems before they become big
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problems and small problems are not always easy for the untrained eye to spot. People are understandably skeptical when they see a crew working on a road that appears to be in good condition while ignoring a rough patch of road right outside their driveway. Faced with vociferous complaints, it’s all too easy to fall back on the “worst-first” syndrome. The Worst First method of pavement management is an easy trap to fall into that dooms the entire road maintenance project. In this method of maintenance you direct funding dollars to fix the roads in the worst condition first. While this sounds like a great idea, what happens is while spending all the maintenance efforts trying to bring the worst roads up to good condition, the good roads fall into disrepair. It is much more effective to spend less money keeping the good roads at a good level and repairing the poor roads as funding permits. The million dollars required to improve a couple miles of bad road from a PCI of 20 up to 80 could better be used to bring 30 miles of arterial roads up from a PCI of 55 to 80. Alternatively, some agencies prefer to use a “worst first” approach. This can skew investment to drive up long term costs for repair. It is best to take a cost/benefit approach of doing work in a timely manner with more weight given to key roads that carry the most traffic, before rehabilitation costs shoot-up. This results in benefiting the most people for the dollar spent. Fortunately, the public is more than capable of being sensible and sympathetic when presented with the facts. People know how important a well-maintained road network is for their community and they also know the importance of spending tax dollars wisely. Preventive maintenance can only work if the program is applied consistently and the program can only be applied consistently if there is a sustained, predictable level of funding. The following Maintenance graph shows the typical relationship between the deterioration of roads over time and the cost of repairing those roads. The deterioration is reported as a Pavement Condition Index, (PCI), and the costs are given in dollars per square foot. You can see how the repair costs, (yellow line), rise exponentially as the condition drops below the 55 PCI minimum target threshold set by the County. It should be noted that although this graph lists “Slurry Seal” as a pavement treatment, the County has chosen to use a “Chip Seal” treatment as a more cost effective method of extending pavement life. This alternate method of sealing still results in a similar pavement deterioration curve.
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To avoid the high cost of reconstruction it is the goal of San Luis Obispo County Public Works to maintain a minimum overall PCI rating for all County roads of not less than 65. This PCI is broken down into a rating of not less than 70 for major arterial roads and a PCI of not less than 55 for local and minor roads. Picture 4-1 shows the results of letting a section of road deteriorate to the level of needing major reconstruction while pictures 4-2 and 4-3 illustrate a, cost effective, planned road overlay with the road condition brought from a PCI of 55 back up to 100.
Major Reconstruction Fig. (4-1)
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Cost effective road maintenance
Road ready for overlay PCI 55 Fig. (4-2)
5.
Completed overlay PCI now 100 Fig. (4-3)
SLO County Road Maintenance Strategy The objective of following a pavement management system is to achieve a point where regularly applied low cost routine maintenance is the primary strategy being applied. With predictable maintenance the county can realize the lowest pavement management costs and impact the driving public the least. Once the roads deteriorate to the point where filling potholes and filling large crack systems takes up most of the maintenance staff time major repairs will be needed and it is too late to apply low cost treatments.
5.1
Pavement Maintenance Strategy
In previous decades road maintenance operations were performed on an as needed basis. As complaints came in from the public repairs were made, roads in very bad condition were overlaid or rebuilt and there was no regular system to ensure the most cost effective treatments were applied to roads. Ten years ago the County began using a Pavement Management System to provide a systematic method for evaluating the condition of county roads. Although an effective PMS will effectively demonstrate the most cost effective combination of maintenance work each year, it should be considered as a management tool to aid Public Works engineers to determine to best maintenance plan to pursue. Pavements are rated from a best condition score of 100 to a worst condition score of zero using a rating system known as a Pavement Condition Index, (PCI). As pavement deteriorates overtime, deterioration occurs in the pavement layer which devalues the pavements expected life and structural adequacy resulting in a lower PCI rating. For example, (as a general estimate), when a roadway has 40% of its surface defected, the PCI would drop to around 60. Following that relationship, when it is at 80% defected, the PCI roughly drops to 20. Defects generally mean cracking in the form of long cracks or closely bunched “alligator” cracking but they may also include sever weathering, bleeding through of oil or push-outs of pavement. The goal of any pavement management program is to catch the rehabilitation of the pavement while it is still cost
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effective to rehabilitate, before it needs major reconstruction. The following graph illustrates the exponential cost increase by deferring maintenance to the point where serious reconstruction is required. A newly built road begins to deteriorate shortly after being built. Water leaches materials out of the asphalt, volatile oils evaporate off, sunlight breaks down oils and continuous pounding of traffic breaks down the pavement. Regular maintenance applications can be very effective in extending the useful life of asphalt pavement. The chart below shows the cost comparison of applications over the life of pavement. Each BST, (Bituminous Surface Treatment, i.e. chipseal, sealcoat), brings the PCI up and extends the life longer. If the road is maintained and overlaid at a PCI greater than 60 the costs will be minimal. As shown with the blue line ignoring maintenance results in failure of the road and very expensive reconstruction costs.
Table 5-1 shows the repair strategy used in conjunction with the pavement management program to aid in the decision process. Generally costs are based on historical costs. Crack seal was derived by taking 12 section samples from various locations, averaging the square footage of cracks for each section and then calculating an average cracks per mile ratio. This number was then divided into the cost of a current crack seal contract which was based on a per mile sealing of cracks. Digout and replace was based on recent Cal-Trans contracts. Hand patching is based on an educated estimate.
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Distress Description Low Alligator Cracking
Moderate Alligator Cracking
Severe Alligator Cracking with poor Base Minor Rutting or Pushout
Major Rutting or Pushout
Severe Raveling
Minor Raveling
Minor Longitudinal or Transverse Cracking, 1/4 to 3/4" Major Longitudinal or Transverse Cracking, > 3/4" Minor Edge Cracking
PCI 75-80
50-60
Department of Public Works and Transportation
San Luis Obispo County Road System
Board of Supervisors District 1, Harry Ovitt District 2, Bruce Gibson District 3, Jerry Lenthall District 4, Khatchik “Katcho” Achadjian District 5, Jim Patterson
Prepared by
Department of Public Works Paavo Ogren, Director Glen Priddy, Deputy Director Operations Dave Flynn, Deputy Director Administration Jim Berg, Roads Analyst
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Table of Contents Page 1. Introduction .....................................................................................................5 1.1 Pavement Management.....................................................................5 1.2 Routine Maintenance Activities......................................................5 1.3 Pavement Preventative Maintenance Program ............................5 1.4 Current Conditions........................................................................ 6-7 3. Revenue.............................................................................................................8 3. Expenditures ....................................................................................................9 3.1 Revenues vs. Expenditures ..............................................................9 3.2 Maintenance Operating Costs ................................................. 10-11 3.3 Road System Capital Outlay Projects .................................... 11-13 4. Preventative Maintenance..................................................................... 13-15 5. SLO County Road Maintenance Strategy .................................................16 5.1 Road Maintenance Repair Strategy........................................ 16-18 5.2 MicroPAVER............................................................................... 20-22 5.3 Maintenance program results and budgets .......................... 22-24 6. Conclusion.......................................................................................................24 Bibliography .......................................................................................................25 Appendices..........................................................................................................26 Appendix A – Indirect Road Costs .............................................. 27-31 Appendix B– Pavement Distresses ............................................... 32-33 Appendix C –Five Year Listing of Planned Overlay Projects ........................................................ 34-40 Appendix D – Complete listing of all San Luis Obispo County roads with pavement condition rating.................. 41-95
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1 Introduction County Government is responsible for providing a safe and healthy environment for its citizens. Toward that end the Department of Public Works is tasked with maintaining the County road system infrastructure and associated structures, in the County of San Luis Obispo. Road system structures include: • 1315 miles of roads, comprised of; o 1084 miles of paved roads o 231 miles of gravel roads • 207 Bridges • 4,300 road drainage culverts • 47 Flood Control Basins for roadside drainage. • 12,200 Road signs • Traffic signals at 17 locations around the County • 102 miles of Sidewalks • 1220 Sidewalk ADA ramps
1.1
Pavement Management
The primary investment in the county road system is in paved road surface. Since 1997, the Public Works Department has maintained a formal pavement management system for documenting road conditions and forecasting needed improves and funds for the system. It is utilized to manage pavement conditions so the system does not deteriorate below acceptable standards. The Department maintains the roads using a field staff of 75 employees to perform routine maintenance duties. Routine maintenance involves roadway patching, shoulder maintenance, signs and striping, mowing and tree trimming, culvert repair/replacement, bridge maintenance, and correction of right of way drainage issues and other activities.
1.2 • • • •
Routine Maintenance Activities Repair deficiencies in the road system, clearing slides, repairing washouts, etc. Tasks which help prevent further deterioration of the road system, such as crack sealing and patching. Proactive preventative maintenance tasks, such as scheduled culvert cleaning to prevent greater damage at a later date. Tree and brush removal to improve public safety or prevent greater damage from falling trees.
These activities, while critical to safe operations for the public, do little to extend the life of the infrastructure.
1.3
Pavement Preventative Maintenance Program
In conjunction with the routine maintenance work the road system requires regular preventative maintenance on all roads to achieve the greatest cost/benefit ratio. On non-paved roads this means routine grading and graveling and shoulder maintenance. On paved roads maximum life is realized with a formal pavement management program. Pavement preventative maintenance activities are tasks such as; seal coat, chip seal and pavement overlay.
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Current Pavement Conditions In February of 2008 an annual survey of 25% of County paved roads was completed. This survey results in a Pavement Condition Index rating being assigned to each section of paved road surveyed. Pavement Condition Index or PCI is a scale of 0-100 that rates the condition of pavement with a value of less than 10 being failed pavement and 100 being perfect pavement. Using this rating scale the overall condition for all paved county roads in May 2008 was 63.1. The following data and tables are based on pavement condition resulting from that pavement condition survey.
Pavement Conditions 2008 Road Classification
PCI for Class
Road Miles
% of Total
Bad 0-20
Poor 21-40
Fair 41-60
Good 61-80
Best 81-100
Miles
%
Miles
%
Miles
%
Miles
%
Miles
%
Arterials
73
104
10%
0.35
0%
5
6%
11
17%
38
31%
49
45%
Collectors
63.3
420
39%
11.58
3%
49
13%
96
29%
121
25%
143
30%
Local Roads
60.5
560
52%
15.11
3%
76
16%
114
30%
196
30%
159
22%
Total County
63.1
1,084
100%
33
3%
141
13%
303
28%
303
28%
303
28%
Conditions by Road Classification. Table 2-1
Pavement Condition Areas in SLO County. Fig 2-1* *Pavement Condition Areas are selected to group similar environmental and traffic impact on pavements and differ from Road Maintenance Sections.
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REGION
Average PCI February 2008
Area 1
59.4
Area 3 Area 4
65.2 67.5
PCI by Region. Table 2-2
Pavement Rating by Community Community
Average PCI Feb. 2008
Avila Beach
84.3
Cambria
66.4
Cayucos
72.9
Los Osos
64.3
Nipomo
67
Oceano
65.4
San Miguel
52.9
Santa Margarita
42.7
Shandon
46.8
Templeton
69
PCI by Community. Table 2-3
Miles of Paved Road by PCI Category PAVEMENT CONDITION Road Miles 2006 Road Miles 2007 Road Miles 2008
Bad 0-20 11 14 33
Poor 21-40 67 138 150
Fair 41-60 344 255 239
Good 61-80 365 365 343
Best 81100 334 304 320
Avg.* PCI 68.0 68.9 67.6
Deferred Maintenance (2007 dollars) $62,000,000 $84,125,593 $103,652,569**
Road conditions for last three years. Table 2-4 *note: this PCI is the rating at the time of inspection, other charts may show the PCI at the time work is applied. **2008 increase in costs reflects an adjustment to the construction cost tables from previous years to account for increased construction costs.
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2.
Revenue
The County road system is supported by revenue from a number of sources. Because funding generally fluctuates with economic changes maintenance cost must be constantly monitored and adjusted to match income. Since voters approved Proposition 42 in 2004, the County has received revenue from the sales tax on motor fuel. While the funds have been divided among various transportation needs by the legislature, we expect $3.6 million annually which provides the basis for preventative maintenance work.
Roads Major Revenues And Expenditures $18,000,000
$16,000,000
$14,000,000
$12,000,000
$10,000,000
$8,000,000
$6,000,000
$4,000,000
$2,000,000
$0 03/04 Property Tax
04/05 ISTEA
05/06 Prop 42
06/07 General Fund
07/08 TDA
Gas Tax
08/09 Maintenance
Road revenue sources compared to Maintenance costs. Table 2-1
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3.
Expenditures
When road revenues are the same or reduced, maintenance work must be cut back with the potential for disastrous and costly results. As the cost of “routine” maintenance increases less money is left for preventative maintenance. Routine maintenance costs rise due to the cost of complying with unfunded mandates, (such as stricter environmental compliance), increased material and labor costs and rising equipment costs.
3.1
Expenditure distribution
R o a d F u n d s B u d g e t e d E x p e n d i t u r e s fo r F Y 2 0 0 8 /2 0 0 9 M a jo r C o n s tr u c tio n P r o je c ts , $ 1 2 ,8 6 0 ,0 0 0
M a in te n a n c e , $ 1 2 ,4 4 5 ,0 0 0
Pa v e m e n t O v e r la y , $ 6 ,4 9 4 ,0 0 0
U n d is tr ib u te d E n g in e e r in g , $ 4 ,0 3 0 ,0 0 0
Road Fund Expenditures Table 3-1
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3.2
Maintenance Operating Costs
County Tree Crew Dealing with fallen trees. Fig. 3-1
Routine Maintenance Cost Distribution for San Luis Obispo County in 2007
S ig n s , S tr ip in g & M a r k in g s 4% R o a d D r a in a g e 8%
A ll O th e r R o a d W o rk* 9%
P o th o le p a tc h in g 8%
A d m in is tr a tio n 4% M a jo r R o a d R e p a ir 23% M a te r ia ls $ E q u ip . H a n d lin g 2%
G r a v e l R d . M a in t. 7% T r e e T r im m in g & Remov al 16% R o a d s id e M o w in g 2%
S h o u ld e r M a in t. 14%
B r id g e R e p a ir /M a in t. 2%
S to r m D a m a g e 1%
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Maintenance Costs. Table 3-2
Routine Maintenance costs 2007 Pothole patching Administration Major Road Repair (1) Materials & Equip. Handling Bridge Repair/Maint. Shoulder Maint. Storm Damage Roadside Mowing Tree Trimming & Removal Gravel Rd. Maint. Road Drainage Signs, Striping & Markings All Other Road Work (2) Total in 2007
$ $ $ $ $ $ $ $ $ $ $ $ $
248,379 715,111 279,765 1,702,682 763,474 138,779 521,161 601,871 511,156 210,213 439,422 309,368 1,662,942
$
8,104,324
Table 3-3 (1) Major Road repair is less the cost of repairs included in capital projects such as overlay preparation. (2) other work includes; drainage channels, sidewalks, gravel pit reclamation, and guardrail work.
The maintenance costs shown in table 3-2 are operating costs and do not include capital projects such as pavement overlays or bridge reconstruction. Road crews are increasingly tasked with maintenance of structures not directly tied to road maintenance. Some of these tasks include: • Storm water basins, road culvert and channel maintenance o The Federally mandated NPDES program requires a large commitment of time and materials by road crews to assure compliance with storm water runoff rules. o More basins and channels to contain storm water are required and must be maintained. o Down drain inlets and associated storm water filters must be cleaned regularly. • Environmental restoration o Extra care must be taken to assure minimum environmental damage from road work o Roadside repair work must be carefully restored in environmentally sensitive areas. • Sidewalk repair o More residential streets now include sidewalks o Sidewalks installed years ago are now reaching the point where the require repair or reconstruction o Recent court rulings have forced the county to maintain a higher standard for sidewalk pavement • ADA ramps and facility maintenance o Federally mandated ADA compliance now requires curb ramps for all sidewalks o Older ADA ramps may not comply with current rules and are aging to
11
•
3.3
where they require replacement Roadside Bike lane sweeping and maintenance o As population increases and more people bike along roadsides crews must increase the level of maintenance o The addition of bike lanes requires sweeping of road shoulders that previously needed little attention
Road System Capital Outlay Projects
Widening of Vinyard Drive bridge. Fig. 3.2 In 2007 approximately 40 miles of roads have been overlaid to date in San Luis Obispo County with a 2 ½” – 4” asphalt overlay. Due to the tremendous rise in the cost of asphaltic oil, gravel aggregate and labor costs, paving prices have increased exponentially from the 1990’s. In 2007 the average cost per mile for overlaying county roads was $245,000 per mile for the average 26.6 foot wide county road. The cost breakdown for paving in 2007 is as shown:
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A / C O v e r la y C o s t 2 0 0 7
P e r m it s , $ 1 4 3 . 0 0
D e s ig n , $ 1 1 ,1 7 8 .0 0
P r e . E n g in e e r in g , $ 5 ,2 7 6 .0 0
C o n s t r u c t io n , $ 8 ,3 2 2 ,2 4 1 .0 0
•
•
4.
M a in t e n a n c e C r e w Pr e p ., $ 1 ,4 7 9 ,5 1 2 .0 0 C o n tr a c t P r o c e s s in g , $ 5 ,2 9 5 .0 0 U t ilit y C o o r d in a t io n , $ 8 6 0 .0 0
The table in appendix C is a listing of roads scheduled for pavement overlay. It should be understood that this list of roads requiring work is subject to the discretion of the Road Maintenance Division Manager. There may be considerations beyond the scope of the pavement management system that determine the priority of overlay projects or chip seal treatments. There are no scheduled roads for chipseal coating at this time.
Preventative Maintenance Why do Preventative Maintenance?
Preventive maintenance is a way of managing investment dollars in the infrastructure to maximize the cost/benefit or rate of return. This strategy is a systematic method of performing road repairs and rehabilitation based on a logical and predictive program rather than fixing problems as they arise. When it comes to roads, people tend to think locally not globally. It is the pothole at the end of the driveway, the rough pavement near the school and the ruts in the nearby intersection that they are concerned about and that puts municipal engineers on the spot. Routine maintenance must deal with these local near term local issues. Preventative maintenance needs to assure a strong, long term, investment foundation. Preventive maintenance is all about fixing small problems before they become big
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problems and small problems are not always easy for the untrained eye to spot. People are understandably skeptical when they see a crew working on a road that appears to be in good condition while ignoring a rough patch of road right outside their driveway. Faced with vociferous complaints, it’s all too easy to fall back on the “worst-first” syndrome. The Worst First method of pavement management is an easy trap to fall into that dooms the entire road maintenance project. In this method of maintenance you direct funding dollars to fix the roads in the worst condition first. While this sounds like a great idea, what happens is while spending all the maintenance efforts trying to bring the worst roads up to good condition, the good roads fall into disrepair. It is much more effective to spend less money keeping the good roads at a good level and repairing the poor roads as funding permits. The million dollars required to improve a couple miles of bad road from a PCI of 20 up to 80 could better be used to bring 30 miles of arterial roads up from a PCI of 55 to 80. Alternatively, some agencies prefer to use a “worst first” approach. This can skew investment to drive up long term costs for repair. It is best to take a cost/benefit approach of doing work in a timely manner with more weight given to key roads that carry the most traffic, before rehabilitation costs shoot-up. This results in benefiting the most people for the dollar spent. Fortunately, the public is more than capable of being sensible and sympathetic when presented with the facts. People know how important a well-maintained road network is for their community and they also know the importance of spending tax dollars wisely. Preventive maintenance can only work if the program is applied consistently and the program can only be applied consistently if there is a sustained, predictable level of funding. The following Maintenance graph shows the typical relationship between the deterioration of roads over time and the cost of repairing those roads. The deterioration is reported as a Pavement Condition Index, (PCI), and the costs are given in dollars per square foot. You can see how the repair costs, (yellow line), rise exponentially as the condition drops below the 55 PCI minimum target threshold set by the County. It should be noted that although this graph lists “Slurry Seal” as a pavement treatment, the County has chosen to use a “Chip Seal” treatment as a more cost effective method of extending pavement life. This alternate method of sealing still results in a similar pavement deterioration curve.
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To avoid the high cost of reconstruction it is the goal of San Luis Obispo County Public Works to maintain a minimum overall PCI rating for all County roads of not less than 65. This PCI is broken down into a rating of not less than 70 for major arterial roads and a PCI of not less than 55 for local and minor roads. Picture 4-1 shows the results of letting a section of road deteriorate to the level of needing major reconstruction while pictures 4-2 and 4-3 illustrate a, cost effective, planned road overlay with the road condition brought from a PCI of 55 back up to 100.
Major Reconstruction Fig. (4-1)
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Cost effective road maintenance
Road ready for overlay PCI 55 Fig. (4-2)
5.
Completed overlay PCI now 100 Fig. (4-3)
SLO County Road Maintenance Strategy The objective of following a pavement management system is to achieve a point where regularly applied low cost routine maintenance is the primary strategy being applied. With predictable maintenance the county can realize the lowest pavement management costs and impact the driving public the least. Once the roads deteriorate to the point where filling potholes and filling large crack systems takes up most of the maintenance staff time major repairs will be needed and it is too late to apply low cost treatments.
5.1
Pavement Maintenance Strategy
In previous decades road maintenance operations were performed on an as needed basis. As complaints came in from the public repairs were made, roads in very bad condition were overlaid or rebuilt and there was no regular system to ensure the most cost effective treatments were applied to roads. Ten years ago the County began using a Pavement Management System to provide a systematic method for evaluating the condition of county roads. Although an effective PMS will effectively demonstrate the most cost effective combination of maintenance work each year, it should be considered as a management tool to aid Public Works engineers to determine to best maintenance plan to pursue. Pavements are rated from a best condition score of 100 to a worst condition score of zero using a rating system known as a Pavement Condition Index, (PCI). As pavement deteriorates overtime, deterioration occurs in the pavement layer which devalues the pavements expected life and structural adequacy resulting in a lower PCI rating. For example, (as a general estimate), when a roadway has 40% of its surface defected, the PCI would drop to around 60. Following that relationship, when it is at 80% defected, the PCI roughly drops to 20. Defects generally mean cracking in the form of long cracks or closely bunched “alligator” cracking but they may also include sever weathering, bleeding through of oil or push-outs of pavement. The goal of any pavement management program is to catch the rehabilitation of the pavement while it is still cost
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effective to rehabilitate, before it needs major reconstruction. The following graph illustrates the exponential cost increase by deferring maintenance to the point where serious reconstruction is required. A newly built road begins to deteriorate shortly after being built. Water leaches materials out of the asphalt, volatile oils evaporate off, sunlight breaks down oils and continuous pounding of traffic breaks down the pavement. Regular maintenance applications can be very effective in extending the useful life of asphalt pavement. The chart below shows the cost comparison of applications over the life of pavement. Each BST, (Bituminous Surface Treatment, i.e. chipseal, sealcoat), brings the PCI up and extends the life longer. If the road is maintained and overlaid at a PCI greater than 60 the costs will be minimal. As shown with the blue line ignoring maintenance results in failure of the road and very expensive reconstruction costs.
Table 5-1 shows the repair strategy used in conjunction with the pavement management program to aid in the decision process. Generally costs are based on historical costs. Crack seal was derived by taking 12 section samples from various locations, averaging the square footage of cracks for each section and then calculating an average cracks per mile ratio. This number was then divided into the cost of a current crack seal contract which was based on a per mile sealing of cracks. Digout and replace was based on recent Cal-Trans contracts. Hand patching is based on an educated estimate.
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Distress Description Low Alligator Cracking
Moderate Alligator Cracking
Severe Alligator Cracking with poor Base Minor Rutting or Pushout
Major Rutting or Pushout
Severe Raveling
Minor Raveling
Minor Longitudinal or Transverse Cracking, 1/4 to 3/4" Major Longitudinal or Transverse Cracking, > 3/4" Minor Edge Cracking
PCI 75-80
50-60
