Bus Network Structure: Maintaining short wait times for RTA bus transfers

RTA operates as Hub-and-Spoke which is "the most efficient configuration" according to an official report.

Photo: Riverside Transit Agency

Transit Talking Points by: Nicholas Ventrone, Community Engagement Director

The Riverside Transit Agency has some more service changes planned for the future. Many are very promising. The bus agency had some big reports published within the Board of Directors and Committee agenda packets a few weeks ago. One of my jobs is to go through these reports and share what I believe is important to you. One such report is the Draft Service Standards Report, published on June 4, 2014. Scroll down to page 17 of the committee agenda packet to view it.

This report will guide RTA in ensuring that its service meets the expectations of passengers and taxpayers. There's quite a bit of good and productive data in this packet including recommendations to expand later evening services, route classifications, and recommended procedures of addressing low-ridership lines of which I will break down in future Let's Debates and Transit Talking Points. For now, the topic of discussion is RTA's network structure and a potential consideration to restructure the bus routes in the downtown Riverside area from hub-and-spoke to grid. This issue is important because the bus network design affects bus transfer wait times.

Here's what the report had to say about the bus route network design structure in its full context:

The design of a route network defines the overall success of the system. How routes interact with one another greatly impacts the ease with which passengers can travel around the network.

Network Structure: The RTA service area is comprised of varying levels of population and employment densities and urban centers separated by geographic gaps of little to no density. RTA serves areas with a variety of mobility needs and service warrants: some areas are supportive of transit lifestyle service while others warrant lifeline service. Working within a constraint of limited resources, RTA must strive to match resource investment to mobility needs to ensure maximized gains from ridership. Its challenge is creating a cohesive network that combines areas that warrant different levels of service investment and transit supply.
The RTA bus system network operates as hub-and-spoke where routes connect with each other at one or more centralized transfer hubs or transit centers. Preliminary recommendations may call for a decentralized grid-based system for some routes. For up-to-date scheduling and maps for trip planning, visit the RTA website.

Due to its incredibly large service area, RTA operates as a hub-and-spoke network. This is the most efficient configuration for connecting such a large area, but it means that many trips involve at least one transfer. To reduce total travel time and encourage passengers to use the system, RTA should aim to schedule no transfer wait to be more than 20 minutes.

The report went on and recommended that RTA work with connecting transit providers to coordinate transit service terminals, schedules, and transfer mechanisms. The Riding in Riverside transit blog also has an accurate description about RTA's network design when a reader posted a question in a blog post. Here is the full context of the conversation:

Anonymous 14 November, 2012 17:35 - To be honest, the 2 million will barely cover the expense to add bus bays, and improved amenities. I don't expect things to improve much at this point in time. Also, don't the current RTA routes, at least in Riverside try to emulate a grid, such as routes 1, 10, 12, 13, 14, 15. Or is this due to the city's design. Likewise, Moreno Valley routes emulate a grid, though less so than the Riverside routes.

JN - 19 November, 2012 18:17: No, RTA runs a hub-and-spoke system. A grid system would see routes along most major streets, and transfers would happen at each corner where you wanted to turn, eg. if you wanted to go from Downtown to the airport you'd take a route down Magnolia to Arlington, then transfer to a route running on Arlington. The current system (in both Riverside and MoVal) is oriented towards major transfer points-- the Downtown Terminal and Tyler Mall in Riverside, the Moreno Valley Mall in Moreno Valley. Notice that there aren't many east-west elements in either city, and that all the routes radiate out from central points.

The hub-and-spoke design is vital to ensure timed transfers in Riverside are maintained. RTA was recommended to keep transfer layover times to less than 20 minutes. By the way, the $2 million that the anonymous poster was referring to was previous funding for the Riverside Transit Center. Since then, the $7 million that was secured for the downtown transit project was re-purposed to the Twin Cities Transit Center in November, 2012 due to trivial regulatory rules with awarded funds.

Another report that I ran across was RTA's Fiscal Year 2015-2017 proposed Short Range Transit Plan. The report had an update of what officials have planned for the Riverside Transit Center:

The current transit center is located between Fairmont Boulevard and Market Street off of University Avenue and Mission Inn Avenue. The COA includes a separate task that evaluates the relocation of the transit center and has a proposed option that includes a decentralized grid network with the use of Metrolink station site and the Vine Street site as layover areas for a few routes. The implementation date of this change is yet to be determined.

A similar recommendation for a decentralized grid network was mentioned for the Moreno Valley/Perris Region. Here is the full context of the preliminary FY16 and FY17 recommendations:

  • Invest in productive service along Magnolia Avenue, University Avenue, and Arlington Avenue to foster “lifestyle” transit that is faster and provides more frequency;
  • Consolidate services connecting downtown Riverside and the Tyler Galleria into fewer, more productive routes;
  • Divert less productive service away from key corridors; and
  • Enhance the customer experience by integrating both local and regional network.
Moreno Valley/Perris:
  • Move from a hub-based network to a grid system by increasing frequency on key linear corridors such as Alessandro Boulevard and Perris Boulevard;
  • Realign service on the eastern end of Moreno Valley and Perris near Moreno Beach Drive to create a more efficient and effective network; and
  • Improve regional mobility at major hubs such as the Moreno Valley Mall and Perris-Station Transit Center.
Hemet/San Jacinto/Pass:
  • Focus service where transit is most productive by making Florida Avenue and State Street more frequent network spines;
  • Streamline service into a more efficient and effective network;
  • Enhance both regional and community connections by facilitating transfers at Hemet Valley Mall and Beaumont/Banning Wal-Mart.
  • Reorient transit from an all-day fixed route network to one tailored to specific mobility needs; and
  • Improve community and regional connections to attract new riders.

Regarding the hub-and-spoke to grid proposal for the downtown area, I will be reviewing the COA-recommended route design and recommended service frequencies when they are completed later this fall. Generally speaking, engineering timed transfer points between each bus route that run fewer than one bus every 15 minutes under a decentralized grid network is very difficult to attain. RTA needs to ensure the timed transfer layover does not exceed 20 minutes. In addition, each route going into downtown should eventually connect to the downtown train station whenever a train is due to pass through.

One of the best solutions to solve the problems associated with the Riverside Transit Center, of which we've advocated, is for the City of Riverside to designate the Metrolink station site as an enterprise marketplace job zone where a private developer can build up a multistory job site, replace the surface parking lot with structured parking over retail, expand the bus bay capacity to maintain hub-and-spoke bus routing, streamline the traffic flow in and out of the station area, and build a pedestrian bridge over the 91 freeway in return for an inclining tax break. This solution means not having to wait for years on in to get a robust multi-modal transit hub for the people of Riverside.

We're looking for a problem solver to take the lead on moving this project forward.