| We developed a technical process that related existing transit
service supply in Western Riverside County, California by service
types or categories to current and future population and employment
densities. The goal was to develop a plan that would meet the “basic
transportation needs” of the county. The process and plan
were needed because of the lack of an adequate transit forecasting
model, little transit service in most of the study area, extraordinary
growth forecasts (population growing from 950,000 in 1990 to 2 million
by 2010), and extreme air quality attainment problems.
Some of the techniques used to develop the plan are discussed in
this article. Full copies of the Long Range Transit Plan (LRTP)
and technical analyses are available from the author.
Background
In late 1993, PB was asked to develop an LRTP that would be integrated
into the Western Riverside County Comprehensive Transportation Plan,
which we were developing under an existing contract with the Western
Riverside Council of Governments. The LRTP was developed with the
assistance of all the thirteen transit operators and the regional/subregional
planning agencies in Western Riverside County. The results were
reviewed and approved in April 1994 by three policy making boards
including the Riverside Transit Agency, the Riverside County Transportation
Commission and the Western Riverside Council of Governments.
Goals and Transit Service Types
The Western Riverside County LRTP was intended to meet the goals
of providing:
- Transit services to meet the intra-city and intra-community
basic transportation needs
- Transit services to meet the inter-city and inter-community
basic transportation needs
- Transit services to meet the needs of commuters (work trips)
in Western Riverside County to and from the counties of Los Angeles,
Orange, San Bernardino, and San Diego
- Transit service for intercity and intracounty work trips
- Intensified local transit service within identified urban centers
- Specialized services for the elderly and disabled, and for
special events when needed and warranted.
From these goals we developed transit service types and categorized
them as follows:
- Local Oriented
– Intra-Community (Goal 1)
– Inter-Community (Goal 2)
– Urban Centers (Goal 5)
– Specialized Services (Goal 6)
- Commuter Oriented
– Inter-County/Express Bus (Goal 3)
– Inter-County/Commuter Rail (Goal 3)
– Intra-County/Express Bus (Goal 4).
This article focuses on the techniques used to estimate the service
needs for the Intra-Community Basic Transportation Needs (Goal 1).
The full report estimates the vehicle requirements, annual revenue
vehicle service hours, annual operating costs, annual farebox revenues,
and annual unlinked transit trips for each service type listed above
without the use of a travel forecasting model.
Many of the other techniques used for the other service type estimates,
available in the full report, may also be of interest to readers.
Intra-Community Basic Transportation Needs
Intra-community basic transportation needs were defined by a combination
of population and employment densities and transit-dependency. Transit-dependency,
using 1990 census data, was determined by whether a community or
area fell into two or more of the following categories:
- More than 20 percent of the population aged 65 and over
- More than 13 percent of families classified as being below
the poverty level
- More than 9 percent of the households with no automobiles
- More than 50 percent of the households with only one automobile.
The above thresholds were approximately 50 percent higher than
the County averages. This provided a strong indicator that the communities
that passed the thresholds were much more transit dependent than
other areas of Western Riverside County.
Transit dependency, population and employment densities, and amount
of service supply were then blended to develop seven service categories
for the following years: 1990 (calibration year), 2000, and 2010.
It was also required that a city or census place be identified as
“transit dependent” in the years 2000 and 2010, which
required some judgment calls from the local demographers because
it dramatically changes the amount of transit service needed as
shown below.
An analysis relating population density (persons per acre) and employment
density (employees per acre) was done in relation to the amount
of service supply (measured as annual revenue vehicle service hours,
RVSH) that should be provided. This analysis was based on the cities
and census places and existing service supply characteristics and
it required allocating service supply by area.
It was assumed that most of the service currently provided was designed
to meet the “basic transportation needs” of Western
Riverside County. Only recently had service been started that related
to the other transit service goals listed above. It is possible
to separate all services by services types in a metropolitan area
and apply similar analysis techniques.
The service related criteria (Table 1) were applied to the 1990,
2000 and 2010 population and employment characteristics for the
cities and census places in Western Riverside County. Each city
and census place was assigned a category and the annual RVSH was
calculated based on the population of each area.
Summary
In Western Riverside County, there are 37 identified cities and
census places, with 6 places identified as transit dependent. In
applying the service related criteria, the amount of annual RVSH
was estimated at:
- 344,000 (120 peak buses) in 1990
- 578,000 (212 peak buses) in 2000
- 782,000 (290 peak buses) in 2010.
The process also allocated the amount of service hours among the
37 areas and allowed for an equitable distribution of transit service
based on this rational criteria. This allocation was helpful in
adopting the overall plan and in the discussion of service priorities
between the competing transit service types.
This approach had the advantage of relating service supply directly
to community demographics and allowed the planners and decision-makers
to have a more realistic or hands-on relationship to the needs of
the different communities. It also allowed for a very rational and
lively discussion of future demographic forecasts because it so
impacted the amount of transit service to be deployed to the different
communities. |
