Roads under construction
New roads will be paved this week and next

The road improvement work for 2019 is nearly completed. Paving is currently scheduled for the following days:

• Glenhill Drive – Thursday, Oct. 24
• MacDonald Drive – Friday, Oct. 25
• Morgan Court / Circle – Friday, Oct. 25
• Taft Road – Saturday, Oct. 26
• Lexington Boulevard South – Monday, Oct. 28

The work on Cady Street had been delayed due to the discovery of a Great Lakes Water Authority (GLWA) power feed during excavation. City staff, Fleis & VandenBrink, Nagle Paving, GLWA and GLWA's contractor developed a solution that involved laying down a new conduit, which now encases a new power feed. With that repair now complete, road construction is back on track. Weather depending, the new concrete curbs and sidewalks will be poured on Cady Street on Thursday, Oct. 24. Once the concrete has cured (approx. 5 or 7 days), Nagle Paving will begin fine grading and paving operations. That work is tentatively scheduled for Nov. 1.

For current road construction updates, please refer to a special web page set up by Fleis & VendenBrink, the City’s engineering consulting team.


What is the street millage costing you?


Property owners in Northville can assess their cost for the street bond by using the online calculator. You can find your taxable value on your summer 2018 tax statement or by looking up your property here: property tax and assessing lookup. The taxable value is no more than half of the market value. The calculator multiplies your taxable value by 0.00098.


Calculate Your Estimated Cost

To determine your estimated additional cost for the street bond, multiply your home's taxable value by .00098.

Example:

Home's Taxable Value $125,000

Multiply $125,000 x .00098 $122.50

Your calculator...

Enter your home's taxable value: $   

Your estimated additional cost: $ 


City of Northville has a plan to prioritize road repair and replacement

There’s a science to determining how roads should be repaired or replaced, balanced by practicality and traffic flow.

The process of evaluation and analysis starts with rating roads using the Pavement Surface Evaluation and Rating (PASER) system, an industry-standard assessment in which trained analysts drive each segment of road (from intersection to intersection) and score it from one (the worst) to 10 (a new road). Roads rated 7 or 8 may require routine maintenance, such as crack sealing or minor patching. Roads rated 4-6 are considered to be in “fair” condition and may need preventive maintenance, such as an overlay or joint repairs. Roads rated less than 4 are candidates for extensive repairs or reconstruction.

After each segment is rated, Roadsoft, a pavement management software, is used to define the type of repair, its cost and the allocated budget, to determine the most cost-effective way to attain the best overall condition for the roadway network (roads owned by the City). The software also defines how many lane miles of each type of repair must be done to attain the long-term condition goals for the roadway network. The City aims to attain an average rating of 6 OCI (Overall Condition Index) with millage funding.

To determine which roads are the best candidates for the extensive repairs, a Network Priority Rating (NPR) is calculated for each pavement segment. Calculations are based on these five factors: PASER rating, pavement priority, pavement use, segment length, and pavement classification.

Pavement Priority is classified as: 1) low – only residential and mostly local residents; 2) medium – periodic commercial, frequent residential traffic; and 3) high – frequent commercial and high use of local traffic.

Pavement use has four categories: major residential, major commercial and local residential and local commercial. It is related to the location, degree of utilization and expected traffic type/frequency of a particular road segment.

street with patched potholestThe segment length uses calculations developed by the state in its Roadsoft program.

Pavement classification – There are basically five categories: 1) asphalt standard duty, 2) asphalt heavy duty, 3) concrete standard duty, 4) concrete heavy duty, and 5) asphalt overlay composite (asphalt over concrete). Standard vs. heavy-duty is based in part on the thickness of the pavement.

Once the NPR is calculated, all segments that are candidates for a particular treatment are determined, based on pavement type (asphalt, concrete, or composite) and PASER rating. These segments are then evaluated using NPR to determine a rating, with the highest values given top priority. Segments are then chosen for repair until reaching the total lane miles of treatment recommended in a particular year.

For example, this shows one year of the City’s long-term strategy:

Type of road Repair Lane miles


 Asphalt Reconstruction   .252  
 Asphalt 3” Mill and Overlay   .256  
 Asphalt Crack Seal   4.062  
 
 Composite 3” Mill and Overlay
 .418  
 
 Composite Crack Seal
  1.389  
 Concrete Asphalt Overlay   .330  

Types of repairs that will improve the road network

Upgrades to roads include reconstruction, mill and overlay, and crack seal repairs for roads made of asphalt, composite and concrete. Reconstruction is a complete tear-down and rebuild; mill and overlay is a process of grinding down the top layer – the wearing layer – and setting down new layers of material (allowing the base of the road to last longer); and crack-seal repairs are used to apply asphalt to a crack to prevent water from seeping into the pavement and potentially creating a pothole.

When scheduling repairs or replacement, practical aspects must be taken into account. For example, when major water main or sewer work is scheduled in a given year, major road repairs on that same section of road would be made immediately following that repair.

Once all streets to be repaired are determined for each year, a manual review is conducted to balance the location of repairs with other construction planned or underway (e.g. construction of new homes or a commercial building). That way, repairs don’t create gridlock in one part of town. With proper planning, multiple repairs can be done sequentially.