Tacoma Streets 101. City of Tacoma - Citizen Neighborhood Street Improvement and Safety Task Force

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1 1 Tacoma Streets 101

2 2 Streets Maintenance Overview Type and amount of streets Condition and types of construction Maintenance and repair methods and costs Sample Project Philosophy/Selection Criteria

3 3 Neighborhood Streets By Type Brick / Concrete, 6.2% Cobblestone, 0.3% Oil Mat, 28.4% Asphalt, 57.9% Sheet Asphalt, 7.2%

4 4 Residential Street Types Sheet Asphalt Oil Mat Cobblestone Asphalt

5 5 Typical Asphalt Road

6 6 Pavement Condition by Neighborhood Council District* Neighborhood Council District Failed / Poor Good / Excellent Central 55% 23% Eastside 48% 34% New Tacoma 49% 35% North East 14% 71% North End 55% 24% South End 54% 25% South Tacoma 49% 33% West End 41% 33% *Based on 2008 Pavement Condition Index (PCI). Does not include streets without pavement rating.

7 7 Pavement Condition Tacoma Network Score Network Score 2011 Future Network Score (10 yr)

8 8 Birth of a Pothole Potholes begin after rain Repeated freezing and As temperatures rise, the When vehicles drive over or snow seeps into cracks and down into the soil below the road surface. The soil turns into mud and with no support, a hole thawing or heavy traffic causes the ground to expand, pushing the pavement up. ground returns to a normal level but the pavement often remains raised. This creates a gap, or hollow space between this cavity, the pavement surface cracks and falls into the hollow space, leading to the birth of another pothole. can form under the pavement. the pavement and the ground below it.

9 9 Permanent Pothole Repair Mark for repair Jackhammer edges Excavate pothole Install asphalt and level Compact asphalt Seal the edges

10 10 Permanent Repair Types Stand alone repair Wheel path repair Lane repair

11 11 Routine Maintenance Crack Sealing Chip Seal (Applying Oil) Chip Seal (Rock over oil) Chip Seal (Compacting)

12 12 Grind and Overlay Typical Failed/Poor Street Removing Failed Pavement Finished Overlay (2008) 4 years later (2012)

13 13 Cape Seal Maintenance Cape Seal uses the advantages of two sealing and rehabilitation methods combined. It is the application of a chip seal followed within a few days by a slurry or microsurfacing. i Chip Seal creates a flexible water tight membrane that seals surface cracks. Slurry Seal eliminates the loose rock, creates a tighter asphalt appearance, increases durability, and reduces roadway noise. Less expensive than Grind and Overlay

14 14 Cape Seal Maintenance Residential Street (Before Maintenance) Residential Street (After Chip Seal)

15 15 Cape Seal Maintenance Residential Street (Finished Cape Seal) Residential Street (5 years after Cape Seal)

16 16

17 17 Pavement Lifecycle Costs

18 18 Types of Street t Improvement and Average Cost of Repair Type of Improvement Permanent Pothole Repair Cape Seal Grind and Overlay New/Reconstruction School Safety Warning Beacons Crosswalk Markings Sidewalks (6ft wide with curb ramps) Average Cost $13.00 per sq. ft. $15,000 per block $100,000 per block $500, per block $90,000 per installation $500 per approach or $2,000 per intersection ti $20,000 per block

19 19 Sample Project List: Staff Philosophy/Selection Criteria Example of how $9 Million per year could be used over six years to make a real and significant improvement in the condition and safety of the City s streets. Widespread d cost effective projects Maximize work performed, reduce delivery time (Minimal Design requirements) Focus on grind and overlay, maintenance, and projects that eliminate or reduce quantity of pot- holes.

20 20 Philosophy Behind Selection Criteria Focus on neighborhoods/residential streets Distribute projects in all Neighborhood Council Districts Safety Improvements School safety beacons Stretch t impact of dollars - Gi Grind and overlay/maintenance Coordinate with public and private utilities Go Fast/Shovel Ready Projects - Grind and overlay/maintenance Local Jobs (Spread the work multiple projects and contracts) Focus on public spaces - Schools, community centers, etc. Complete Streets Curb ramps, sidewalk, bike signs and striping where applicable, etc. Project Continuation Local Improvement District (LID) backlog