Lec 24: Ch1.(T&LD): Urban transportation planning vs. Site planning

Review the transportation-land use cycle (Read examples in Ch.1 & compare the development of the Provo/Orem area)

Understand that accessibility plays an important role (for site planning)

Understand the differences between urban transportation planning and site (transportation) planning

Review of transportation-land use cycle

The construction of a new arterial streets, or major reconstruction of an existing thoroughfare, modifies the accessibility of an area; this, in turn, leads to development and increased traffic demands.

When I was a student some 20+ years ago, the University Parkway was hugged by apple orchards!

Forces that influence the dynamics of land development include…

Governmental policy and programs at the national, state, and local levels

At local level: comprehensive (master, general) plan, zoning ordinance, and subdivision regulations

Changes in family income

Changing family and personal preferences

Transportation technology and cost structure

Transport system changes

Level of Service provided by the urban transport system

Accessibility: The transportation system is the basic infrastructure element which influences the pattern of urban development.

San Diego experience after about 170 miles of freeways have been constructed.

Increased traffic volumes and property values

Change in system LOS

Hypothetical example: accessibility and market area

What this argument wants to say is that the effect of lowered travel speed (longer travel time) will disproportionately affect the market area.

E.g. My wife says “There’s no decent outlets in Utah County! Park City has one, but it’s not as big as the ones in NJ and it’s too far. I would rather run to TJ Max.”

Accessibility: The transportation system is the basic infrastructure element which influences the pattern of urban development (cont)

Change in shopping-center market area

Before the DC beltway construction

After the beltway construction (lighter shade)

Travel time greatly reduced by the Beltway

Trip to multiple malls became feasible (chaining shopping trips)

Accessibility: The transportation system is the basic infrastructure element which influences the pattern of urban development (cont)

Migration of primary retail location (sounds like the Provo/Orem area)

Downtown developed first

Southeast: residential development away from CBD Need for a shopping area within reasonable travel time Mall development

Southeast: Continual development in the southeast area A new mall

Urban transportation planning: summary

4 levels of urban planning process

A very long range horizon for strategic planning of major transportation corridors land use patterns and other permanent elements of the urban environment

An intermediate 20-year horizon for the planning of significant changes in transportation facilities, water, waste water, and other major infrastructure elements and land use patterns

A short-range horizon (5 to 10 years) for planning and programming of major development

Design and construction of individual public works projects and private developments

Urban transportation planning

Site planning

Urban transportation planning: Purpose

Identify major travel corridors and provide projections of the approximate volume of traffic within these corridors

Identify major potential problem areas in the proposed network

Provide a basis for planning and programming major network improvements

Evaluate the compatibility of the future land use and transportation assumptions A macroscopic way of looking at the system

This macroscopic planning cannot provide detail data such as turning volumes and peak hour volumes which are needed for actual physical facility design.

A macroscopic tool does not meet the needs of the microscopic level site-planning

Reliable projections of turn movements at individual intersections or access drives

Reliable projections of the traffic volumes on individual street segments

Reliable estimates of traffic volumes at access drives as for different access locations and/or designs

The effect of numerous access points to an arterial as opposed to only a few direct access points

Left-turn and right-turn requirements

Effects of change in land use

Effects of modest changes in the location of activities

Reliable estimates of the traffic on the frontage roads separate from that or the main lanes of a feeway or at-grade arterial

Site planningSite specific and micro-scale planning involving analysis of

Traffic impact of specific proposed development

Adequacy of the access drives

Stability of the on-site circulation and parking

Can the existing intersection and streets handle increased traffic?

Change in turning movements?

How much extra traffic go through the community?

Site planning (cont)

Requires detailed geometric, traffic, and control data to perform these tasks

See Table 1-2 on pp. 13 & 14.