Using FHWA and several other cost estimation sources, a round number for installing sidewalks in our area is about $20/sq.ft. A very rough measurement for the west side of Alameda, from Aston to Camp Bello, is 1,600 linear ft. The east sidewalks, from Liberty Park to the Y intersection, is about 1,270 linear ft.
So straight math: 2,870 linear feet * 4.5’ width sidewalk (ADA compliant) * $20/sq.ft. = $258k
That $20/sq.ft. has some contingency room, but adding an additional 20% contingency would be $52k. This estimate anticipates using the existing intersection turns. If the existing intersection turns need to be completely redone and the recommended chicanes are included (to preserve heritage trees), there would be increased costs.
The entire Alameda sidewalk project should be in the ballpark of under $400k.
These estimates are much less than the millions that have been tossed around. One advantage on Alameda is that there is an existing pathway with curb, so the grading for elevation is primarily already done and this too helps reduce cost. Adding to cost will be greenery features to protect several heritage redwoods from harm, where the feature will may use a parking space to route the sidewalk around the tree. In other cases these same greenery features could be used plant shrubs/trees to provide additional aspects to emphasize a calmer-quieter roadway.
The following links are helpful, and more cost estimation tools can be searched on the internet.
- Cost to install concrete sidewalk - Estimates and Prices at Howmuch
- Federal Highway Administration on Bicycle and Pedestrian Transportation, July 2006 - FHWA-HRT-05-101 (see section 9.6 where they break out curbs and walkways at $15/lin.ft and $11/sq.ft., respectfully)
- 2018 Install A Concrete Sidewalk Costs | Average Cost To Install A Concrete Sidewalk