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Infrastructure Management covers different aspects of the facilities which the Municipality owns. These will include, but are not limited to:
- Roadway Surface - pavement structure, curb, sidewalk, traffic lights, traffic signs
- Roadway Subsurface - storm and sanitary sewers, water mains, electronics, ductbanks
- HRM Facilities - buildings, parks, trees
- Customer Service - internal and external interaction with HRM staff
Infrastructure Management Services' role within the Infrastructure Management System includes the roadway surface. This includes:
HRM'S Road Network Status
The following are breakdowns of the road network within the core area of the Municipality, as of April 2010.
Type of Roadways :
- 1645 km - Asphalt Pavement
- 3 km - Concrete Pavement
- 80 km - Stone and Oil / Chipsealed
- 36 km - Gravel
Total Road Network - 1764 km
Type of Street Classifications:
- 211 km - Arterial
- 210 km - Major Collector
- 241 km - Minor Collector
- 1102 km - Local
Total Road Network - 1764 km
HRM'S Sidewalk Network Status
The following is a breakdown of the sidewalk network within the core area of the Municipality, as of April 2010.
Type of Sidewalk:
- 809 km - Concrete Sidewalk
- 31 km - Asphalt Sidewalk
- 3 km - Brick / Paver Sidewalk
- 7 km - Exposed Aggregate
Total Sidewalk Network - 850 km
HRM'S Curb Network Status
The following is a breakdown of the curb network within the core area of the Municipality, as of April 2010.
Type of Curb:
- 1724 km - Concrete Curb
- 366 km - Asphalt Curb
- 4 km - Granite Curb
Total Curb Network - 2094 km
PAVEMENT MANAGEMENT
HRM'S Pavement Management Background
Following amalgamation, road network data from the former Municipal units was combined into a single database and loaded into the Pavement Condition Management System (PCMS) software. Using this system and its evaluation criteria, the entire road network within the core area of HRM has now been assessed.
After the field assessment is completed and entered into the computer, a Surface Distress Index (SDI) is assigned to each street; this tells the user what condition the street is in and what the computer suggests as the treatment required. Based on this SDI, computer simulations can be run which will further break down the road network into categories which can be analyzed further. For example, an average SDI can be calculated for the entire Municipality.
HRM'S Pavement Management Objectives and Strategy
An important role of the PCMS is to try and achieve the most effective use of public funds for capital street improvements. This can be done one of two ways:
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If we are assigned a specific amount of funds for street upgrading, we can use the PCMS to tell us where and how to best spend these funds.
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The PCMS can be used to recommend the amount of funding which is required on street upgrading to increase or maintain the value of the existing road network.
Another important role of PCMS is to improve the decisions which are made in relation to street upgrading treatments. This can be looked at in two ways:
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Best First - meaning to place priority on rehabilitating streets which are in the best condition; these are streets in good and fair condition. These treatments are cost efficient so two to three times as many streets can be done. This strategy prevents the streets in good and fair condition from slipping into fair and poor condition. One disadvantage to this approach is the higher operational costs of maintaining the poor streets until it is time for reconstruction.
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Worst First - meaning to place priority on rehabilitating streets which are in the worst condition. While this achieves better taxpayer recognition, it has its disadvantages. The cost of the reconstruction is higher, so fewer streets can be done. The streets in good and fair condition deteriorate to a poorer condition and in time, operational costs will be higher to maintain these streets which are deteriorating prematurely.
We try and take the advantages of both strategies and combine them into one strategy which we call Blending. The cost effectiveness of the Best First is joined to the taxpayer recognition of the Worst First, which we think at this time, is a very realistic strategy for Pavement Management. This Blending strategy leans towards the Best First approach and gives the flexibility needed to manage the streets in our very diverse weather conditions.
HRM'S Pavement Management Performance Measures
The Pavement Management strategies which are implemented in any given year must be compared to other years to see if these strategies are working. For example, after the current years' work is completed, the Pavement Management database is updated to reflect this work. After the database is updated, a computer simulation can be run to compare last years average SDI to the updated SDI. This will show the user different things, mainly, "is the amount of work we are doing enough to maintain the overall SDI of the network or do we need to budget more money?"
This is one example of performance measures, others are comparing the annual backlog and monitoring the street treatments and how they are surviving under actual traffic and weather conditions.
SIDEWALK MANAGEMENT
Our sidewalk inventory consists of a database of approximately 5284 existing sidewalk sections.
Our condition rating is done by physically going out into the field and walking the sidewalk section to be rated. We rate using hand held counters, tallying distresses such as spalling, minor and major faulting (minor being faulting 0 – ½ inch in elevation, major being faulting > ½ inch in elevation), minor and major cracking (minor being cracks < ¼ inch wide, major being cracks > ¼ inch wide), good and poor patching, and good slabs. After we get back into the office, we enter the data into our database software.
The percent defective (no. of defective slabs/total slabs * 100) determines whether or not a sidewalk will be considered for capital work. Usually the higher the percent defective, the greater the chance it will make it into the capital budget. We also qualify with the Sidewalk Deficiency Rating (SDR). The SDR is calculated by weighting the Total Major Defective Slabs at a value of 1, and the Total Minor Defective Slabs at a value of 0.25. This flags the most critical sidewalk sections (those with the most major defects).
When asphalt sidewalk is rated, it is done by assessing the entire length of the sidewalk section and rating it Good, Fair, or Poor.
CURB MANAGEMENT
Our curb inventory consists of a database of approximately 11,719 existing curb sections.
Our condition rating is done by physically going out into the field and walking the curb section to be rated. We rate using hand held counters, tallying distresses such as spalling, minor and major faulting (minor being faulting < 1 inch in elevation, major being faulting > 1 inch in elevation), minor and major cracking (minor being cracks < ½ inch wide, major being cracks > ½ inch wide), major and minor gutter height (major being 3 - 6 inches loss of height, minor being 1 - 3 inches loss of height), and good sections. We then enter the data into a palm pilot on site. After we get back into the office, we download from the palm pilot into our database software.
The percent defective (no. of defective sections/total sections * 100) determines whether or not a curb will be considered for capital work. Usually the higher the percent defective, the greater the chance it will make it into the capital budget. We also qualify with the Curb Deficiency Rating (CDR). The CDR is calculated by weighting the Total Major Defective Sections at a value of 1, and the Total Minor Defective Sections at a value of 0.25. This flags the most critical curb sections (those with the most major defects).
When asphalt curb is rated, it is done by assessing the entire length of the curb section and rating it Good, Fair, or Poor.
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