An innovative sidewalk inventory program implemented for the City of Rancho Cucamonga, CA, is not only resolving safety concerns but will help with various infrastructure improvements and long-term development projects.
Rancho Cucamonga, with a population over 150,000, is located in western San Bernardino County, CA, about 40 miles east of Los Angeles. During the 1970s, the unincorporated communities of Alta Loma, Etiwanda, and Cucamonga experienced rapid and uncontrolled growth due to Los Angeles and Orange County families seeking affordable housing. Citizens were concerned about managing development and voted to incorporate as the city of Rancho Cucamonga in November 1977. In 2006, Money Magazine's annual ‘Best Places to Live 2006' ranked Rancho Cucamonga as #42 nationwide.
According to Associate Engineer Walt Stickney, the city needed to obtain an inventory of missing sidewalk links primarily on its non-local roads.
"When the city was incorporated more than 30 years ago, for various reasons there were a number of developed and undeveloped areas lacking sidewalks," said Stickney. "The community of Alta Loma, for example, was established over a century ago and was predominantly agricultural, consisting of citrus groves and vineyards. Prior to incorporation, being a rural area, development did not always trigger a requirement for sidewalks. Now, being nearly built out, these segments of missing sidewalk are a high priority to the city."
Stickney added that there were two key reasons for conducting the inventory – safety and convenience. The city also plans to use the collected data to improve overall community walkability.
"When you have schools, retirement centers, community centers, and other such facilities requiring pedestrian travel, you provide safe paths of travel where possible," said Stickney. "Along with being safer, paved sidewalks are more user-friendly and encourage walking. This city is very proactive in providing avenues for the public to walk and bicycle, having recently completed a first class trail main-line along the abandoned Southern Pacific Railroad corridor. The joining of sidewalks can also foster economic development in commercial areas."
Carlsbad, CA-based VanderHawk Consulting, LLC was retained to conduct the sidewalk inventory, analyze network-wide coverage and generate required reports.
The goal was to create a centerline representation of sidewalk coverage using a 2009 aerial orthographic photo as a reference point for current sidewalk locations.
Unfortunately, the aerial photo was almost two years old and some sidewalk or missing sidewalk segments weren't visible due to resolution quality or tree canopies. Other visual impediments like shrubs, fences, and K-rails made it challenging to determine if a sidewalk was actually present or not. So field spot checks were performed as an additional quality control measure.
The sidewalk polylines were cleaned up and spliced in specific locations to represent any missing links and segmentation breaks that corresponded to the city's MicroPAVER pavement management segmentation. A green line represented a concrete or asphalt sidewalk; a blue line was used for decomposed granite community trails; and a red line indicated a missing sidewalk link.
Each sidewalk segment contained the following attribute information:
Stickney said the data gleaned from the sidewalk inventory is proving invaluable and has revealed some unusual scenarios.
"In older areas of the city the necessary right-of-way may never had been dedicated," he said. "In these situations the property owners sometimes have extended their walls or other improvements into a future sidewalk alignment. The right-of-way costs and physical obstacles add greatly to the cost of improving the sidewalk. As such, we have to address these occurrences when prioritizing a work program."
As one example, a homeowner built a wall extending to where a proposed sidewalk will be installed. The city will have to determine and resolve this particular right-of-way issue before the sidewalk and other improvements are installed.
Stickney added that the sidewalk inventory is also providing proximity criteria to high-pedestrian zones such as malls, schools, mass transit, hospital, court house, retirement homes and other facilities.
"We're developing a priority matrix that will help the city plan for these improvements. Included in this priority matrix are proximity attributes which are derived from a series of concentric buffer zones around these facilities," he said. "In addition, the type of nearby facility will be assigned a ranking. This can give a greater ranking, or priority, for where to add missing sidewalks. VanderHawk is coordinating its resources with the city's GIS department in developing these buffers and priorities. Of course, developing a work program is not as cut and dry as crunching numbers. We will attempt to consolidate the extent, or limits, of a capital project to avoid being spread throughout the city. This will help in keeping contractor's bids lower, and also reduce wasted travel time for the city's inspectors."
A sidewalk installation program report, scheduled to be delivered to the city in February, will include a segment-by-segment breakdown of installation costs and will summarize data based on factors such as priority ranking, maintenance zone and proposed year of installation.
"We are excited about the development of this useful tool which will enable the City to both quantitatively and qualitatively prioritize sidewalk projects for inclusion into our CIP," said Mark Steuer, Director of Engineering Services/City Engineer for Rancho Cucamonga.
"The bottom line is that this inventory program will provide a master plan toward addressing the construction of missing sidewalks," added Stickney. "The realities of the budget process results in these construction projects being a multi-year program. The first step in most inventory projects is to establish how the inventory will be maintained and current. With this inventory, the quantity of missing sidewalks will only be reduced over time."
SOURCE: VanderHawk Consulting, LLC