Attachment 4Pavement Life Maintenance Costs
This analysis compares the cost of asphalt and concrete pavement for the Almond Grove project
over the life of both of these pavement solutions. This analysis differs from those at previous
Council meetings as the costs are presented in today's dollars. The analysis looks at the
difference in initial construction cost in comparison with anticipated future maintenance and
rehabilitation costs. In summary, the historical performance for the concrete option indicates that
little maintenance will be required over the next 50 years. Asphalt pavement requires more
future maintenance and rehabilitation over the same period of time, which includes crack sealing
and surface seals at periodic intervals. At the end of its initial service life, more extensive
pavement rehabilitation is anticipated with asphalt, which could include a full overlay or
reconstruction. These future maintenance and rehabilitation activities result in higher future
costs over the 50 year period.
During the 2010 conceptual design phase, staff estimated the future maintenance costs using
industry practice for maintenance of asphalt streets. The Town's anticipated maintenance
practice is based on expected resources and other Town -wide priorities for street repair, therefore
at this time staff is assuming a less rigorous treatment schedule. The treatment schedules are as
follows:
Industry Standard Asphalt Maintenance Program: 7 year Slurry Seal, 14 year Slurry Seal,
21 year Slurry Seal, 28 year Overlay, 35 year Slurry Seal, 42 year Slurry Seal, and 49
year Slurry Seal
Town Practice As halt Maintenance Program: 10 year Slurry Seal, 20 year Slurry Seal,
30 year Rubber Cape Seal, 40 year Overlay, and 50 year Slurry Seal
Concrete Maintenance: Industry standard of 3% slab replacement every 14 years
Based on these maintenance schedules, staff from the Finance Department and Town Manager's
Office worked with Parks and Public Works to develop estimated life cycle costs for asphalt and
concrete. The following assumptions were made to calculate these costs:
1. 50 year life cycle
2. Inflation rate of 3% per year for increased cost of supplies, services, etc.
3. Effective Annual Interest Rate of I%. A rate I% was selected as this is the approximate
interest rate that the Town is earning today. The calculations that were done reflect net
present value which is how much money the Town would need to put aside today to
accumulate enough money over the course of the 50 year life cycle to pay for the
projected maintenance costs.
4. Broadway and Bachman have full designs, including the amount (quantity) of pavement.
The other streets have a conceptual design, which is much higher level, and provides
estimates on the amount of pavement. Future maintenance costs for the remaining eight
streets would be reflective of these estimated quantities and costs. The life cycle
estimates provided assume similar costs for all ten streets.
ATTACHMENT
With these assumptions in mind, the table below shows the net present value of life cycle
maintenance costs for Broadway and Bachman as well as all ten streets. The amounts presented
represent the amount of money the Town would need today to pay for these future maintenance
costs.
Table 1: Net Present Value of Future Maintenance Costs
Net Present Value of Future Maintenance Costs
Industry Standard
Town
Industry Standard
Asphalt
Asphalt
Concrete
Program
Pro ram
Program
Broadway /Bachman
Pro ram
Pro ram
Pro ram
Future Maintenance Costs
in 2016 Dollars
$ 1,380,000
$ 1,060,000
$ 360,000
All Ten Streets in Almond
Grove
$ 7,800,000
$ 5,950,000
$ 2,000,000
Maintenance Costs
(in 2016 Dollars)
$ 7,800,000
$ 5,950,000
$ 2,000,000
With the life cycle maintenance estimates, staff is able to project the total project cost over the 50
year life cycle, inclusive of the project reconstruction costs and estimated maintenance costs.
The Table below reflects the total estimated project costs for asphalt and concrete:
Table 2: Estimated Total Project Costs
Estimated Total Project Costs
Industry
Industry Standard
Town
Standard
Asphalt
Asphalt
Concrete
Pro ram
Pro ram
Pro ram
Estimated Reconstruction
Cost
$ 14,127,805
$ 14,127,805
$ 16,741,707
Estimated Maintenance
Cost
$ 7,800,000
$ 5,950,000
$ 2,000,000
Total Estimated Life
Cycle of the Almond
Grove Reconstruction
Project
$ 21,927,805
$ 20,077,805
$ 18,741,707
It is important to note that the assessment of future maintenance costs over the next 50 years is
influenced by many factors which are difficult to predict, including such items as timing of
future maintenance and rehabilitation activities, material cost fluctuations, labor costs, and
inflation to name a few. These are staff's best estimates based on information available today.
Using Town projected street maintenance practices, future maintenance costs for all ten streets
are estimated at $3,950,000 less in concrete than in asphalt over 50 years. When combined with
construction costs, concrete is projected to be $1,336,098 less over the total 50 year life.
ATTACHMENT