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HomeMy WebLinkAboutAgenda Work Session 12-11-07Z:\Council Packets\2007\WS12-11-07\Agenda Work Session 12-11-07.doc Last Printed 12/7/2007 1:51:43 PM NOTICE OF THE WORK STUDY SESSION OF THE FOUNTAIN HILLS TOWN COUNCIL Mayor Wally Nichols Councilmember Mike Archambault Councilmember Keith McMahan Vice Mayor Ginny Dickey Councilmember Henry Leger Councilmember Ed Kehe Councilmember Jay Schlum TIME: 5:00 P.M. – 7:00 P.M. WHEN: TUESDAY, DECEMBER 11, 2007 WHERE: FOUNTAIN HILLS COUNCIL CHAMBERS 16705 E. AVENUE OF THE FOUNTAINS, FOUNTAIN HILLS, AZ ALL WORK-STUDY ITEMS LISTED ARE FOR DISCUSSION ONLY. NO ACTION CAN OR WILL BE TAKEN. The primary purpose of work session meetings is to provide the Town Council with the opportunity for in-depth discussion and study of specific subjects. Public comment is not provided for on the Agenda and may be made only as approved by consensus of the Council. In appropriate circumstances, a brief presentation may be permitted by a member of the public or another interested party on an Agenda item if invited by the Mayor or the Town Manager to do so. The Presiding Officer may limit or end the time for such presentations. WORK STUDY AGENDA 1.) CALL TO ORDER AND ROLL CALL – Mayor Nichols 2.) PRESENTATION AND DISCUSSION of the 2007 Pavement Management Report by Stantec Consulting. 3.) ADJOURNMENT. DATED this 7th day of December, 2007. Bevelyn J. Bender, Town Clerk The Town of Fountain Hills endeavors to make all public meetings accessible to persons with disabilities. Please call 837-2003 (voice) or 1-800-367-8939 (TDD) 48 hours prior to the meeting to request a reasonable accommodation to attend this meeting or to obtain agenda information in large print format. Supporting documentation and staff reports furnished the council with this agenda are available for review in the Clerk’s office. #286 Kingstree Blvd @ Mangrum Court (looking west) #287 Kingstree @ Mangrum Court (looking east) #288 Saguaro Blvd.@ Pepperwood Dr.(looking south) #290 Malta Dr. @ Rand Dr. (looking west) #291 Appian Way @Trevino Dr. (looking south) #292 FH Blvd @ Ironwood Dr. (looking north) #295 Sunridge Dr. @Cactus Flower Way (looking north) PAVEMENT MANAGEMENT SUMMARY PRESENT STATUS REPORT . PAVEMENT MANAGEMENT SUMMARY PRESENT STATUS REPORT Stantec Consulting | Infrastructure Management 8211 South 48th Street | Phoenix, AZ 85044 T 800-827-5870 | F 602 431 9562 | www.stantec.com PAVEMENT MANAGEMENT SUMMARY PRESENT STATUS REPORT EXECUTIVE SUMMARY November 11, 2007 \Fhills\final\Report\FHills Pavement Present Status Report KHv5.doc E.1 Executive Summary INTRODUCTION Infrastructure strategic planning is an essential component in the management of public facilities and is driven by aging infrastructure, population growth and the current reality of dwindling budgets for maintenance management. The emphasis is now being placed on not only knowing the true cost of providing services to the public today, but also understanding what will be required to maintain a certain level of services throughout the life of the asset. In other words, we are moving to sustainable management. OBJECTIVES The Town of Fountain Hills retained Stantec Consulting to perform an update of the Town’s Pavement Management System. The goals of the evaluation will be used to determine: • The overall performance of the Town’s pavement network in order to provide recommended rehabilitation strategies to improve the condition of the Town’s streets Ultimately, the successful completion of this project will allow Town staff to: • Assess/review the current condition of any pavement section, • Predict the future conditions for various budget and service levels, which help: ⇒ identify funding needs and shortfalls ⇒ build support for increased funding ⇒ flag potential performance concerns • Set criteria for applying various maintenance and rehabilitation strategies for each pavement section, • Calculate costs associated with each maintenance/rehabilitation strategy, • Specify various appropriate budget scenarios, and • Prioritize all maintenance and rehabilitation work on a network-wide basis, based on previously specified budget restraints. Pavement management is not just a set of procedures; it is, in fact, a philosophy that requires a significant change in organizational culture both at the community and political level. This change will not occur overnight; however, the Pavement Management Report will provide Town staff with a series of important tools, which can be used to begin the education and communication process. Without taking this necessary action, streets will continue to deteriorate and wear out creating an extremely greater cost to the community in upcoming years. PAVEMENT MANAGEMENT SUMMARY PRESENT STATUS REPORT EXECUTIVE SUMMARY November 11, 2007 \Fhills\final\Report\FHills Pavement Present Status Report KHv5.doc E.2 What is it worth? Q2 What condition is it in? Q3 What do we need to do to it? Q4 How much money do we need? Q6 Questions of Sustainable Asset Management What do we have? Q1 When do we need to do it? Q5 What is it worth? Q2Q2 What condition is it in? Q3Q3 What do we need to do to it? Q4Q4 How much money do we need? Q6Q6 Questions of Sustainable Asset Management What do we have? Q1Q1 When do we need to do it? Q5Q5 Sustainable Asset Management Activities Determine System Value Determine Asset Condition Develop O&M and Capital Work Projects Develop & Analyze Life Cycle Cost Profile Develop System Inventory Prioritize & Determine Work Schedule Sustainable Asset Management Activities Determine System Value Determine Asset Condition Develop O&M and Capital Work Projects Develop & Analyze Life Cycle Cost Profile Develop System Inventory Prioritize & Determine Work Schedule How will we fund it? Q7 Develop Sustainable Funding Model How will we fund it? Q7Q7 Develop Sustainable Funding Model This report is based on a blend of the Town’s own policies, the format used by the American Society of Civil Engineers (ASCE) in assessing pavement infrastructure; the best practices developed by the National Infrastructure Guide of Canada as well as a number of other local municipal agencies. Basic Principles Approach Our approach is firmly grounded in the principles of sustainable asset management and is based upon seven fundamental questions illustrated in the diagram on the right. Though this assignment only required the first few of these questions these are steps taken to assist the Town in moving forward with these principals to sustain its asset infrastructure. These questions are: 1. What do you have and where is it? (Inventory) 2. What is it worth? (Costs/replacement Rates) 3. What is its condition and expected remaining service life? (Condition and Capability Analysis) 4. What is the level of service expectation, and what needs to be done? (Capital and Operating Plans) 5. When do you need to do it? (Capital and Operating Plans) 6. How much will it cost and what is the acceptable level of risk(s)? (Short- and Long-term Financial Plan identified by Town Staff) 7. How do you ensure long-term affordability? (Short- and Long-term Plan resulting from the study) This report and associated recommendations will provide the basis for defining the way towards answering all of these questions. OVERVIEW OF FINDINGS The Town of Fountain Hills has current overall replacement value of $146 million of street infrastructure assets. See summary in Table E 1on the following page. The total cost of immediately required repairs and refurbishments is also included that will bring the assets to an acceptable levels of service. See summary in Table E 2 the following page. PAVEMENT MANAGEMENT SUMMARY PRESENT STATUS REPORT EXECUTIVE SUMMARY November 11, 2007 Fhills\final\Report\FHills Pavement Present Status Report KHv5.doc E.3 Table E 1: Pavement Replacement Value Asset Type Inventory 2007 Replacement Value Street Network 395 lane miles $145,452,912 Table E 2: Current Reinvestment Needs (Backlog) All Asset Categories Asset Type Asset Component Inventory Bring up to Acceptable Level of Service Streets Pavement Network 395 lane miles $8,865,878 2007 Total Backlog $8,865,878 Table E 3 below illustrates the overall rating or network condition score for the pavement networks. The network score varies between zero (0) and one hundred (100), with 0 representing the poorest possible condition and 100 representing the best possible ranking. Table E 3: Network Condition Score Asset Type Asset Component Score 0 - 100 Streets Overall Rating 69 During the pavement management system analyses, pavement performance models were used to estimate the rehabilitation requirements of the Town’s street network for a ten-year period beginning in 2007. By setting a minimal “acceptable” level of service of pavement quality along with using Town supplied traffic volumes and estimated construction and sub-grade properties; each evaluated street segment was analyzed to determine when it would be come in need of repair and the type of repair that would be warranted. As a result of this analyses, it was determined that up to 45 percent of the Town’s street network is in need of some form of maintenance or repair in 2007, with an estimated cost of $8.9 million. In general, the results indicate that the Town’s current processes and budgets are maintaining the streets at a reasonable level of service when compared to other growing municipalities regarding overall pavement performance. However, given the current age of the Town’s infrastructure and continuing rising cost of construction, is not uncommon to see an accumulated build up of rehabilitation projects. Having said this, it is imperative the Town continue its efforts at cost effectively reducing the current backlog of poor streets and performing a more aggressive routine and preventative maintenance on those streets currently in good condition. PAVEMENT MANAGEMENT SUMMARY PRESENT STATUS REPORT TABLE OF CONTENTS November 11,, 2007 FHills Pavement Present Status Report KHv5.doc i Table of Contents EXECUTIVE SUMMARY E.1 INTRODUCTION ..........................................................................................................................1 OBJECTIVES................................................................................................................................1 Basic Principles Approach.....................................................................................................2 OVERVIEW OF FINDINGS ..........................................................................................................2 1. STREETS 2 INTRODUCTION ..........................................................................................................................2 WHAT DO WE HAVE? .................................................................................................................2 WHAT IS IT WORTH? ..................................................................................................................3 WHAT CONDITION IS IT IN?.......................................................................................................4 Surface Distress Index (SDI) .................................................................................................4 Riding Comfort Index.............................................................................................................6 Pavement Quality Index.........................................................................................................8 Specific Conditions ................................................................................................................9 WHAT DO WE NEED TO DO?...................................................................................................10 WHEN DO WE NEED TO DO IT? ..............................................................................................11 Minimal Acceptable Levels of Pavement Performance........................................................12 HOW MUCH MONEY DO WE NEED?.......................................................................................14 Scenario 1 - Planned Budget...............................................................................................15 Scenario 2 - Do Nothing.......................................................................................................15 Scenario 3 - Unconstrained “Need Driven” Budget..............................................................15 Discussion of Results...........................................................................................................16 HOW DO WE ENSURE LONG-TERM AFFORDABILITY? ........................................................18 RECOMMENDATIONS...............................................................................................................18 FUTURE PAVEMENT MANAGEMENT STRATEGY .................................................................20 APPENDIX A~ PAVEMENTS ~ STREET LISTING AND NEEDS ASSESSMENT A PAVEMENT MANAGEMENT SUMMARY PRESENT STATUS REPORT Streets November 11, 2007 FHills Pavement Present Status Report KHv5.doc 2 1. Streets INTRODUCTION The Town of Fountain Hills street network currently consists of 395 lane miles of pavement spanning different traffic functional classes. The pavement condition update recently conducted by Stantec determines the overall performance of the Town’s pavement network in order to provide recommended rehabilitation strategies to improve the condition of the Town’s streets. WHAT DO WE HAVE? The street network that serves the Town consists of a series of asset components ranging by traffic functions from local residential to major arterial thoroughfares. The data used to compile the pavement inventory was extracted from the Town’s Geographical Information System (GIS) and the pavement management system databases. These components have been identified in Table1 below: Table1: Pavement Network Database Statistics Major Arterial Roadways: Major arterials roadways are high traffic volume, full access-control roads with intersection spacing dictated either by designated major highways or by key access points located on other inter-regional facilities. Asset Component Traffic Volumes Street Segment Count Network Street Mileage Network Lane Mileage Functional Class Average Annual Daily Traffic (traffic count - high/low ranges) # mi mi Alleys 25-50 24 3.2 6.4 Local Street 200 – 1000 919 98.6 198.3 Minor Collector 1000 – 3000 129 14.1 28.2 Major Collector 3000 -7500 230 28.5 82.4 Minor Arterial 7500 – 15000 192 26.6 59.6 Major Arterial 10000 20000 16 7.9 19.5 Total Pavement Network 1510 178.9 394.4 PAVEMENT MANAGEMENT SUMMARY PRESENT STATUS REPORT Streets November 11, 2007 FHills Pavement Present Status Report KHv5.doc 3 Minor Arterial Roadways: Minor arterial roadways are moderate traffic volume, full or partial access control roads that provide service to retail, commercial and industrial land uses. Minor arterial roadways may develop into principal arterials if traffic volumes increase due to an increase in area development. Major Collector Roadways: Major collector roadways carry a relatively high volume of traffic within larger neighborhoods and can accommodate the traffic volumes generated by minor retail and other commercial services. These streets are intended to provide convenient traffic movement and access to the arterial roadways. Minor Collector Roadways: Minor collector roadways, identified by wide travel lanes, provide access to larger cul-de-sac subdivisions. Developers may use this roadway classification, at Town Council discretion, to provide single access for up to 90 dwelling units without need for a secondary access road. Note: A full description of the traffic functional classification of streets is specified in the Town’s general plan. WHAT IS IT WORTH? The estimated replacement value of the street network and associated appurtenances, based upon current dollar value (2007) is $146 million. Table 2 and associated Pie Chart provide a breakdown of the contribution of each of the network components to the overall system value: Table 2: Pavement Network Replacement Value Asset Component Quantity 2007 Replacement Cost * Replacement Value Pavement type sq feet $ / sq ft $ Flexible Asphalt 30,302,690 $ 4.80 $145,452,912 Total Pavement Network 30,302,690 $145,452,912 *Note: The replacement costs were measured by construction costs + 20% allocated for overhead. Overhead includes; engineering services, contingency, and administration costs along with cost allocations (to other departments). These must be considered when setting budget plans, both in terms of operating as well as capital improvements. PAVEMENT MANAGEMENT SUMMARY PRESENT STATUS REPORT Streets November 11, 2007 FHills Pavement Present Status Report KHv5.doc 4 Pie Chart 3: Street Network by Functional Classification Local Street 50% Minor Collector 7% Major Collector 21% Minor Arterial 15% Major Arterial 5%Alleys 2% As can be seen from the pie chart above, the Town’s Local streets make up 50% of the pavement system. WHAT CONDITION IS IT IN? The overall condition can also be termed as “present status”. The present status component of the pavement management software is extremely important in that it readily provides useful data to the user and provides the base necessary for subsequent analysis. The objective of the present status analysis is to provide updated performance information on the complete pavement network broken down by functional class, and as a whole, allows the Town to evaluate: • The deterioration of streets as determined by the performance indicators; and, • The overall change in the network performance indicator distributions over time. Surface Distress Index (SDI) The surface condition of a street is rated in terms of the type, severity, and extent of pavement distresses present at the time of the survey. The severity reflects how bad the problem is, and is rated in three categories as; slight, moderate or severe. For example, map, longitudinal and transverse cracking are rated as follows: 1. Slight, if cracks less than ½” wide 2. Moderate, if cracks are between ½” and 1” in width 3. Severe, if cracks are wider than 1” The extent refers to how much of the pavement is affected by a distress for each severity. The following distresses itemized in Table 4 were rated for flexible pavements: PAVEMENT MANAGEMENT SUMMARY PRESENT STATUS REPORT Streets November 11, 2007 FHills Pavement Present Status Report KHv5.doc 5 Table 4: Surface Condition Distresses The extent and severity of each distress type that are present on the streets are combined using different weighting factors to generate a Surface Distress Index (SDI) for each pavement section. These ratings can range from “0” to “100”. A value of “100” indicates that the surface of the street section is free of distress and a value of “0” indicates that the surface is severely distressed. An SDI value of 70-75 generally marks the point at which the distresses are becoming significant. A plot showing the SDI distribution for 2007 is shown in Table 5. The network mean SDI for Fountain Hills is 79. Generally speaking the majority of the network is in “good” condition. The plot also shows that 56.5 percent of the network has SDI scores in the 80-100 range, which indices that these pavements have little or no distress. This is indicative of the moderately aggressive routine maintenance program the Town has been successful in implementing. Approximately 29 percent of the network has an SDI score less than 70, which indicates that the pavement is beginning to deteriorate at a faster rate. Table 5: Performance Indicators Surface Distress Index (SDI) by lane miles Patching Edge Cracking Rippling/Shoving Alligator Cracking Raveling/Streaking Potholes Bleeding/Flushing Map Cracking Distortion Longitudinal/ Transverse Cracking Excessive Crown Wheel track Rutting Below 70 distresses become significant Below 70 distresses become significant PAVEMENT MANAGEMENT SUMMARY PRESENT STATUS REPORT Streets November 11, 2007 FHills Pavement Present Status Report KHv5.doc 6 The 2007 summarized distress listing for the entire street network is presented in Appendix A Riding Comfort Index Roughness of the pavement is measured in a longitudinal profile calculated electrically by sensors mounted on the front bumper of Stantec’s Road Tester (RT3000) data collection vehicle. Roughness measurements are correlated to an assessment of ride quality. This subjective assessment is termed the Riding Comfort Index (RCI). The resulting RCI values can range from 0 to 100 in value. A value of 80 to 100 indicates an extremely smooth ride and a value of 0 to 20 indicates an extremely rough ride. These extreme values (100 and 0), however, are generally unachievable. Ride values of 60 to 80 are measured as “good”. Values in the 40 to 60 range often indicate a pavement that is “fair” and soon becoming in need of rehabilitation such as an overlay. Finally, RCI values in the 0 to 40 range are indicative of pavements in “poor” to “very poor” condition. The network average RCI for the Fountain Hills network is 71 which indicate that much of the network exhibits a “good” riding comfort. Table 6 below, illustrates a standard roughness scale published by the American Association of State Highway and Transportation Officials (AASHTO) Table 6: Standard AASHTO Roughness Rating Scale 80 - 100 0 - 20 Poor ride quality is the first indication to the public that the streets are in need of repair. The rougher the streets the more stress traffic has on its roadways, not to mention the wear and tear on the vehicles. This causes the public to repair their vehicles sooner than expected as well as further premature failure to the Towns streets. The Ride Comfort Index (RCI) distribution for 2007 is shown in Table 7, on the following page. Pavements with RCI values in the range of 40 to 60 are considered to have marginal ride quality characteristics. The plot shows roughly only 46 lane miles, or 11.8 percent of the Fountain Hills pavement network, fall into this category. Approximately 342 lane miles, or 88.1 percent of this network have RCI values greater than 60, which is indicative of “good” ride characteristics. Very poor20 -40 40 -60 60 -80 Very Poor Poor Fair Good Very Good PAVEMENT MANAGEMENT SUMMARY PRESENT STATUS REPORT Streets November 11, 2007 FHills Pavement Present Status Report KHv5.doc 7 Table 7: Performance Indicators Ride Comfort Index (RCI) by lane miles The 2007 Summarized Ride Comfort listing for the entire street network is presented in Appendix A. Structural Adequacy Index The structural adequacy of a pavement indicates the pavement’s ability to carry expected traffic loads while providing an acceptable level of service. The structural adequacy of a pavement is determined by analyzing the measured deflection of the pavement under a controlled loading condition and comparing this response to the maximum allowable deflection associated with anticipated loading conditions. The subgrade strength is a key function of the type of subgrade material supporting the pavement. Subgrade strength is grouped into one of three general categories: ‘Strong’, ‘Fair’, and ‘Weak’. This designation is used as a variable in long-term pavement performance modeling, and can be used in the decision making process to identify feasible strategies for pavement sections requiring rehabilitation. Below 40 Poor Ride Comfort Very GoodGoodFairPoorVery Poor 40 Below 40 Poor Ride Comfort Very GoodGoodFairPoorVery Poor 40 PAVEMENT MANAGEMENT SUMMARY PRESENT STATUS REPORT Streets November 11, 2007 FHills Pavement Present Status Report KHv5.doc 8 Presently the Town’s pavement program is setup such that 100 percent of the sections in the defined network are defaulted to a subgrade strength of ‘strong’. The basis behind this is that Arizona soils provides good moisture content of native materials, density, and the local drainage conditions of Fountain Hills provide reasonably good runoff. This is sufficient from a network level study; however, the Town may want to consider updating the default pavement structural data with actual information from existing and/or new information sources to determine more accurate results. Fountain Hills has a good mixture of adequate street base material to support various traffic loads, however, there is a percentage of clay soils that exists within the Town. Therefore, while subgrade values may be sufficient for residential streets, additional care must be taken on collectors and arterial streets due to higher traffic loads and volumes. Pavement Quality Index The Pavement Quality Index (PQI) is used to provide a single overall assessment of pavement quality. The PQI is based on one or more of the basic Performance Indicators - the Surface Distress Index (SDI), the Riding Comfort Index (RCI) and the Structural Adequacy Index (SAI). One mathematical model for calculating the PQI was used in this study, PQI = f(SDI, RCI, SAI). This model uses the SDI as the primary variable in conjunction with the RCI and SAI. The PQI is adjusted downward for RCI scores less than 100. The magnitude of the adjustment increases as the RCI score decreases. An adjustment is also made to account for the degree of structural adequacy / inadequacy of the pavement as determined by the SAI. The PQI is adjusted upward for structurally adequate pavements and downward for structurally inadequate pavements. As with the RCI, SAI and SDI, the PQI varies between zero (0) and one hundred (100), with 0 representing the poorest possible pavement, and 100 representing the best possible pavement. See Table 8 for a standard condition rating scale: The custom scale is also provided to illustrate a more simplistic view broken down into three basic categories. Typical values for a newly constructed street range from 95 to 100. The PQI level at which a pavement becomes in need of rehabilitation is typically in the 40 to 70 range, for lower traffic volumes and 40 to 75 for streets with higher traffic volumes. PAVEMENT MANAGEMENT SUMMARY PRESENT STATUS REPORT Streets November 11, 2007 FHills Pavement Present Status Report KHv5.doc 9 Table 8: Standard Pavement Condition Rating Scale (PQI) Specific Conditions A plot showing the aged PQI distribution in 2007 for the entire network of the Town of Fountain Hills is shown in Table 9 on the following page. The Town of Fountain Hills pavement network mean aged PQI for 2007 is 69 and generally speaking is a network that is in “good” condition. The plot illustrates that the Town’s street network is even distributed. A PQI value less than 40 is indicative of a pavement providing an overall poor level of service. Approximately 19 lane miles or 4.8 percent of the network is in this category. On the other hand, the majority of the network 55.2 percent is in the “good” to “excellent” range (70 or better) which is providing a good level of service to the Town. Distress Index Structural Index Roughness Index Excellent Failed Very poor Poor Fair Good Very good 0 10 25 40 55 70 85 100 Unsatisfactory Adequate 0 55 100 70 PQI Standard PQI Rating Scale Custom PQI Rating Scale Distress Index Structural Index Roughness Index Excellent Failed Very poor Poor Fair Good Very good 0 10 25 40 55 70 85 100 Unsatisfactory 0 40 100 PQI Standard PQIRating Scale Custom PQI Rating Scale Degraded PAVEMENT MANAGEMENT SUMMARY PRESENT STATUS REPORT Streets November 11, 2007 FHills Pavement Present Status Report KHv5.doc 10 Table 9: Performance Indicators Aged Pavement Quality Index (PQI) for 2007 The 2007 summarized pavement quality index listing for the entire pavement network is presented in Appendix A and lists each individual section's PQI, RCI, and SDI by section. WHAT DO WE NEED TO DO? After a pavement section has been determined to be “in need” of rehabilitation, potential rehabilitation alternatives can be generated. To achieve this goal, a list of potential alternatives and some of their characteristics must be specified. This list should include all of the rehabilitation alternatives the agency would consider to rectify a wide range of pavement deficiencies for all pavement types in the network. In addition, to determine the return on investment, a benefit level must be assigned to each rehabilitation alternative. This benefit level allows the after rehabilitation PQI of the section to be estimated. Stantec used a decision tree approach to determine the technically feasible rehabilitation alternatives for each section. The basic philosophy behind this approach is to maximize flexibility. In this regard, the decision trees are completely user defined to ensure that the process accurately models the decision process employed by the agency. Decision trees Below 70 Rehabilitation or repair is recommended Below 70 Rehabilitation or repair is recommended PAVEMENT MANAGEMENT SUMMARY PRESENT STATUS REPORT Streets November 11, 2007 FHills Pavement Present Status Report KHv5.doc 11 should exist for every combination of functional classification and pavement type to accommodate potential differences in decision logic between the various combinations of alternatives. Table 10 below, presents the rehabilitation strategies and associated unit costs provided by Town personnel. Table 10: Rehabilitation Alternatives (Base year 2007) Description Unit Cost $ /ft2 Thick. Factor Benefit Level After Rehab PQI Treatment Trigger Slurry Seal $0.23 0.1 1- Surface Treatment 88 Minor Maintenance Micro Surfacing $0.26 0.1 1- Surface Treatment 88 Minor Maintenance 2” Edge Mill & Overlay $1.07 2.0 2- Edge Mill & O/L 96 Major Maintenance 2” Full Mill & Overlay $1.40 1.8 3- Full Mill & O/L 96 Major Maintenance Reconstruct 3” AC / 6” AGB $4.80 9.0 5- Reconstruction 100 Rehabilitation Note: It is recommended that a review of the defined alternative unit costs and base years be periodically undertaken to ensure that the cost results produced by the pavement management program are as accurate as possible. The alternatives to be considered should be rehabilitation oriented and include such treatments as overlay, mill and overlay, and reconstruction. General surface treatments such as chip sealing and slurry sealing can also be specified, but items such as crack sealing and skin patching, which are applied to localized areas within a section, are considered to be routine maintenance activities and therefore should not be included in the rehabilitation analysis. WHEN DO WE NEED TO DO IT? In order to estimate future rehabilitation requirements of a pavement network over a period of time, the first step is to determine when a pavement section requires rehabilitation. As pavements depreciate, the rate of decrease depends on many factors but it can be demonstrated that these key factors include: the traffic loading conditions, subgrade strength and the properties and thickness of the pavement structure layers. These factors have been set up in the pavement management system based on information provided by Town personnel and are used to prioritize the rehabilitation requirements for the network of pavements over a period of time. This period of time, typically ten years, is known as the programming period. The Need Year of a pavement or when it requires rehabilitation is defined as the year in which the value of the pavement drops to or below a predetermined service level or minimum acceptable quality. Table 11 below shows typical pavement performance triggers and when they occur with the combination of “thin” pavement thickness’, “medium” traffic volumes (collector) and “strong” subgrade strength: PAVEMENT MANAGEMENT SUMMARY PRESENT STATUS REPORT Streets November 11, 2007 FHills Pavement Present Status Report KHv5.doc 12 Table 11: Pavement Performance Triggers Minimal Acceptable Levels of Pavement Performance This minimum acceptable performance is measured using the PQI value. The minimum PQI levels are selected to: • Maintain/improve the existing level of service of the entire network • Provide the system with sufficient backlog to drive the rehabilitation program The minimum PQI levels (or PQI trigger levels), for the Town of Fountain Hills are set by traffic functional classification. Typically the upper functional classification pavements have PQI triggers set higher than the local functional classification pavements, reflecting the users demand for higher levels of service on the upper functional classification streets. The selection of the minimum PQI levels, for the Town of Fountain Hills , represents a ‘balance’ between maintaining the existing level of service and keeping the backlog manageable. The current minimum acceptable PQI’s used by the Town are shown in Table 12 below. The minimum acceptable PQI’s are entered on the top line of the decision tree process. The minimum acceptable PQI’s can be represented by a horizontal line across the performance curve models. 30 0 10 20 30 40 50 60 70 80 90 100 010 20 Minor Maintenance Rehabilitation Replacement Major Maintenance Thresholds Minor Maint Thresholds Major Maint Thresholds Rehabilitation Thresholds Reconstruction Time (years) for Majors StreetsMinimal Acceptable PQI Pavement Quality Index (PQI)AC Collectors 30 0 10 20 30 40 50 60 70 80 90 100 010 20 Minor Maintenance Rehabilitation Replacement Major Maintenance Thresholds Minor Maint Thresholds Major Maint Thresholds Rehabilitation Thresholds Reconstruction Time (years) for Majors StreetsMinimal Acceptable PQI Pavement Quality Index (PQI)AC Collectors PAVEMENT MANAGEMENT SUMMARY PRESENT STATUS REPORT Streets November 11, 2007 FHills Pavement Present Status Report KHv5.doc 13 Table 12: Current Minimum Acceptable PQI Values FUNCTIONAL CLASS MINIMUM ACCEPTABLE PQI TRIGGER Alleys Local Street Minor Collector 70 Major Collector Minor Arterial Major Arterial 75 As streets continue to deteriorate due to inadequate maintenance (funding or neglect), they often exhibit distresses and other characteristics in which maintenance type activities are no longer viable options, therefore, they become in need of rehabilitation. The cost for rehabilitation as opposed to maintenance can be as high as 5 times greater, and as a result, fewer miles of streets can be serviced for the same amount of available budget dollars. Once streets fall below a PQI of 30 or 40, they generally need extensive treatments to the overall pavement structure. Full reconstruction involves the complete removal and replacement of the pavement surface and selective or full replacement of the street base and/or sub-base. Often reconstruction can also involve curb, gutter and other drainage repairs that can be readily attributed to the street deterioration. Reconstruction is extremely costly (over 10 times the cost of maintenance) and will eat up any available budgets in no time. In addition the work is often a lengthy and disruptive process and a nuisance in the eyes of the public. Table 13 on the following page presents a distribution of the sectional Need Years over a ten-year programming period for the Fountain Hills street network. The sections with a Need Year in the first year of the programming period represent the sections that have become in need of rehabilitation in 2007 as well as those sections which were in need of rehabilitation before 2007 but which have yet to receive rehabilitation. Therefore, a portion of the sections in need of rehabilitation in the first year of the programming period represents the prior backlog. 49 percent of the street network in Fountain Hills is in need of maintenance or rehabilitation in 2007. PAVEMENT MANAGEMENT SUMMARY PRESENT STATUS REPORT Streets November 11, 2007 FHills Pavement Present Status Report KHv5.doc 14 Table 13: Need Year Distribution The need driven rehabilitation recommendations for the entire street network is provided in detail by street segment in Appendix A. This text report will include the need year, the selected rehabilitation alternative as well as the cost of the selected alternative. HOW MUCH MONEY DO WE NEED? The amount of funding required can be determined by identifying the optimal rehabilitation strategy for each pavement section. This process is based on three parameters; 1) the need year for a section, 2) selecting from a ‘pool’ of feasible rehabilitation strategies and 3) determining the economic impact of implementing these strategies. The optimal strategy is determined using life cycle economic analysis techniques, which involve an assessment of both the effectiveness of each strategy and an estimate of the capital cost to implement the strategy. It is possible to generate a rehabilitation program based on an economic analysis for a programming period. This is accomplished by knowing the present condition of each section in the network, having a comprehensive pavement prediction performance model, and a set of decision criteria. To determine how much funding is needed, the Town’s pavement management system priority programming analysis is utilized and will generate alternative rehabilitation programs for various budget stream scenarios. PAVEMENT MANAGEMENT SUMMARY PRESENT STATUS REPORT Streets November 11, 2007 FHills Pavement Present Status Report KHv5.doc 15 Three (3) separate 10-year budget scenarios have been generated for the years 2007 through 2016, for comparison. They include: • Scenario 1 - Planned Budget ~ $1.2 Million Annually • Scenario 2 – Do Nothing • Scenario 3 – Unconstrained “Need Driven” Budget Scenario 1 - Planned Budget The first phase of the rehabilitation analysis introduces an annual or “planned” budget as a constraint. This Existing Budget scenario uses the approved annual expenditure to generate a 10-year rehabilitation program. In this case, potential rehabilitation projects must compete against each other for funding based on cost effectiveness. Table 15 on page 17, identifies the resulting PQI from implementing the approved budget of $1.2 million per year. With this approach, the current PQI of 69 would slowly increase to 83 at the end of year 2010 and then slowly decrease to 78 by the end of 2016. Scenario 2 - Do Nothing The do nothing or zero capital expenditure program will demonstrate the network condition over a ten-year period if no action or remediation is taken to rehabilitate the Town’s streets. The results of this approach, the current aged PQI of 69 would slowly decrease to 37 towards the end of 2016. Scenario 3 - Unconstrained “Need Driven” Budget The Unconstrained Budget scenario is essentially a needs analysis. It assumes that there is an unlimited amount of funding and labor, equipment and material resources available. As a result, any pavement section that requires some treatment will be treated with the appropriate rehabilitation solution in the year that it should be treated, for the greatest long- term benefit. One of the common results of any Needs Analysis is that it always recommends large rehabilitation expenditures in the first year of the analysis period. This occurs because, with unlimited funds, the network Pavement Quality Index (PQI) is more effectively increased with immediate expenditures, rather than waiting to spend them. This analysis usually results in significant fluctuation from one year to another. Table 15(need driven budget), identifies the approximate expenditures that would be required to meet the annual treatment needs of the Town of Fountain Hill’s pavement network. This scenario assumes that the correct treatment would be applied in the correct year, to maximize pavement life. With this approach, the current PQI of 69 would raise to 88 in year one and then slowly decline to 77 at the end of 2016. While a needs analysis (Unconstrained Budget) is not practical, it does have value. It identifies the true needs of the system, without bias. PAVEMENT MANAGEMENT SUMMARY PRESENT STATUS REPORT Streets November 11, 2007 FHills Pavement Present Status Report KHv5.doc 16 Table 14: Need Driven Pavement Rehabilitation ~ Summary by cost by Strategy /yr Rehabilitation Year Slurry Seal Micro Surfacing 2” Full Mill & Overlay Reconstruct 3” AC / 6” AGB Total 2007 $1,915,705 $716,607 $5,288,220 $945,346 $8,865,878 2008 $133,250 $29,613 $162,863 2009 $166,019 $70,345 $236,364 2010 $312,571 $120,221 $432,792 2011 $507,028 $102,236 $609,264 2012 $579,859 $164,371 $744,230 2013 $658,664 $146,817 $805,481 2014 $316,248 $93,428 $409,676 2015 $160,143 $38,255 $198,398 2016 $123,670 $27,532 $151,202 Total Network $4,873,157 $1,509,424 $5,288,220 $945,346 $12,616,147 Discussion of Results Each of the above scenarios will yield a different resultant network PQI at the end of the analysis period. The comparison of the three (3) scenarios can illustrate how adequate the planned budget for the Town of Fountain Hills’s pavement network is, over the analysis period. These results of the budget analysis are summarized in the Network Performance Summary Report presented in Table 15 on the following page. This report can be a powerful tool in that it allows the user to easily examine the effect of a specified budget stream on the performance characteristics of the network. Other sensitivity analyses, such as the effect of variations in rehabilitation unit costs, required pavement serviceability levels, and rehabilitation policies as reflected by the decision process can now be easily adjusted on future analysis. The network average PQI at the end of 10 years is predicted to be 78 for the $1.2 million existing annual budget. This will leave 21% of the network below the minimum PQI or remain deficient at the end of the 10 year analysis period. Current reinvestment needs (backlog), or the amount required to bring the assets to an acceptable condition, is $8.9 million for pavements. The backlog is also shown in Table 15 on the following page in the first year of analysis (2007) under the “need driven” category. Note: An inflation factor was used to convert the costs from 2007 to an equivalent unit cost for the implementation year of the proposed rehabilitation alternative. The inflation rate was set at 2% per year. PAVEMENT MANAGEMENT SUMMARY PRESENT STATUS REPORT Streets November 11, 2007 FHills Pavement Present Status Report KHv5.doc 17 Table 15: Network Performance Summary – (3 Scenarios) PAVEMENT MANAGEMENT SUMMARY PRESENT STATUS REPORT Streets November 11, 2007 FHills Pavement Present Status Report KHv5.doc 18 HOW DO WE ENSURE LONG-TERM AFFORDABILITY? The accumulated investment of public funds expended to construct and maintain a pavement network generally amounts to a substantial figure. The Town of Fountain Hills contains 395 lane miles of paved streets. Together, these streets represent approximately 30 million square feet of pavement. At an average replacement cost of $4.80 per square foot, for the pavement construction costs, (i.e., 20% for drainage improvements, design, inspection, and other overhead and administrative costs have been included) this represents an infrastructure asset value to replace the entire street network in excess of $146 million in today’s dollars. Total replacement is not a feasible plan to long-term affordability. In order to implement a less expensive approach, information concerning the condition of the network, its rate of deterioration, and the impact of maintenance and rehabilitation efforts on pavement serviceability levels are required. It is therefore necessary to monitor the performance of each section of the pavement network on an ongoing basis. The Town is well on its way to the ongoing monitoring of a comprehensive pavement management system. We trust this report and associated recommendations will provide the basis for defining the direction moving forward towards answering the question of ensuring long-term affordability in pavement management. RECOMMENDATIONS 1. Planned Annual Budget: In reviewing the results of Table 15, it is evident that a $1.2 million annual budget for the pavement network is sufficient to maintain the current average PQI. Based on the “Need Driven” analysis results for the first three to four years of the analysis period, it appears that the planned annual budget is a realistic amount to expect in order to be able to maintain the residential street network at the desirable level of service. 2. Outlook in next 3-4 years: Although Table 15, provides a predicted pavement network performance outlook for a ten-year period, it should be noted that due to the after rehabilitation PQI specified in the decision process, it is unrealistic to rely on the predicted results for a period beyond three or four years. Therefore, it is recommended that the budget and “needs” trends for the street network should be derived from the results of the first three or four years of analysis only. 3. Minimal Acceptable Levels of Pavement Performance: Adjustments to the minimal acceptable levels (triggers) has direct impact on the expected level of service of the Town’s pavement performance. Setting PQI triggers too high causes annual rehabilitation budgets to become unaffordable and the system becomes inefficient in terms of the length of time between overlays (the higher the PQI trigger, the more PAVEMENT MANAGEMENT SUMMARY PRESENT STATUS REPORT Streets November 11, 2007 FHills Pavement Present Status Report KHv5.doc 19 frequent the rehabilitation cycle). Setting the PQI triggers too low results in an insufficient amount of backlog selected for rehabilitation and the overall performance of the network will deteriorate with time. PQI triggers that are too low also result in a larger number of sections being selected for ‘heavier’ rehabilitation. Earlier intervention, that is a higher PQI trigger, allows ‘lighter’ rehabilitation strategies to be implemented. The 10-year PQI target was selected to maintain the entire Town of Fountain Hills pavement network at its current level of service, which is in the “good” range. A 10- year backlog of between 10% and 25% is desirable. Above 25%, the backlog may become unmanageable and below 10%, the Town may be spending more money than is necessary on street rehabilitation. Since the backlog for the Town is currently at 49%, it is recommended for a long term effect that the Town continue to be proactive in their maintenance strategies which allow for ‘lighter’ rehabilitation strategies to be triggered in the pavement management system. 4. Schedule Regular Condition Updates: It is recommended that the Town continue to collect pavement condition data so the present status or condition of the streets is monitored on a regular basis. This is particularly important given the Town’s desire to maintain the street network condition at reasonable level of service. This will also limit the reliability of the prediction of future pavement performance and recommended rehabilitation programs to a three-to-four year analysis period. 5. Annual Update Program: Another way to monitor the pavement network and maintain the integrity of the data is to update a portion (1/3rd) of the network annually. With this approach we usually recommend that the network be divided in a geographic one-third area. As a result, the network is current every three-year cycle so no section is more than two cycles (years) old. Therefore, the result of the maintenance & rehabilitation analysis is more accurate when using the most recent data to determine the program plans from a year-to-year basis. This also creates an annual budget for the operation and upkeep of the pavement management and keeps it in the forefront in the minds of the stakeholders so this system is not neglected and only looked at every three years. 6. Present Status and Needs Analysis: Based on the results outlined in this report the Town’s street network is currently providing an adequate level of service. However, the analysis also indicates that there are significant backlog requirements as illustrated by the 49 percent of the network with a Need Year of 2007. Given these results, the primary focus for the Town over the next 3-5 years should be to put a program in place to significantly reduce the backlog. With approximately $8.9 million identified in 2007 alone, it may be impractical from a budgetary perspective to attack this backlog over the short term. As a result, to further maximize the street PAVEMENT MANAGEMENT SUMMARY PRESENT STATUS REPORT Streets November 11, 2007 FHills Pavement Present Status Report KHv5.doc 20 improvement budget, total reconstruction work should be limited to those street segments that carry high volumes of traffic or require additional infrastructure renewal such as water, sewer and other utilities. Coordination between these various stakeholders is critical. In addition, despite some of the streets exhibiting poor surface distress and roughness qualities, there appears to be suitable material to provide adequate support of the anticipated traffic loads. As a result, local residential streets may not need to undergo total reconstruction procedures and rehabilitation treatments could be used as viable options. Rehabilitation of these streets may include such alternatives as 1) overlays, 2) mill and overlays, and, 3) slurry applications all of which will help reduce the backlog of work and extend the life of the existing pavements. Any proposed projects should however incorporate proper investigation of the pavement structure and other factors such as drainage which are directly related to the performance of the pavement over time. In order to protect the capital investment the Town of Fountain Hills has already made, it is imperative for public works staff to continue a proactive maintenance approach. The ongoing use of maintenance type strategies such as crack sealing, surface treatments and thin overlays (Micro-surfaces) will extend the life of those streets that are predicted to become needs in greater than 3-4 years from now. This reduces the need for major rehabilitation and reconstruction well into the future. Streets do wear out over time and will eventually need reconstruction. Keeping a backlog of street repair manageable only makes sense and is good practice so the Town does not get caught off guard with a crisis of failing roads. FUTURE PAVEMENT MANAGEMENT STRATEGY By beginning the process of educating the community to the need for sustainable management of the pavement infrastructure, the impacts of resident or user rates can be significantly reduced, especially if a reserve fund is utilized to mitigate the impact of the future peaks in investment needs. We hope this section includes the essential tools which can be used to begin the education/communication process thus providing a systematic process to assist pavement managers and decision-makers in 1) Selecting cost-effective strategies and actions to improve efficiency and safety of their pavement network and, 2) Protecting the investment made in the pavement network. Ultimately, the goal is to provide the citizens of Fountain Hills with a safe and efficient transportation network for all users and protect the value and condition of one of the Town’s most valuable infrastructures for many years to come. We hope the report includes the essential tools, which can be used to begin the education/communication process and through our expertise and determination, we look forward to the opportunity in assisting Town on future projects. PAVEMENT MANAGEMENT SUMMARY PRESENT STATUS REPORT Streets November 11, 2007 A. Appendix A~ Pavements ~ Street Listing and Needs Assessment The Appendix A ~ Pavements ~ Street Listing and Needs Assessment is provided in a separate pdf document provided with this present status report. This street list document is also provided in an electronic spreadsheet format and available for linking into the Towns GIS street centerline file.