§ 18.13. Traffic Impact Analysis (TIA)

The purpose of a TIA is to assess the effects of specific development activity on the existing and planned roadway system. It is the intent of this ordinance to make traffic access planning an integral part of the development process. The thoroughfare network for Cibolo is based on operational values of Level of Service D or better as a criterion for design purpose. Level of Service D is the industry standard and balances vehicle movement, impact on neighborhoods, and costs.

1.

Definitions

Background Traffic - Existing traffic not created or associated with traffic generated by the development.

Projected Traffic Volumes - The number of vehicles that are calculated to be present after a project is completed.

Study Area - The boundaries in which the study is conducted.

Traffic Impact Analysis (TIA) - An in depth analysis of existing and proposed traffic.

Traffic Queue - A line of vehicles stacking in line to make a traffic movement.

Trip Distribution - A percentage estimates trip distribution per turning movement from a development.

Trip Generation Summary - A table summarizing trip generation characteristics of a development for an entire day; including AM and PM peak periods, rates, units and assumptions used to calculate the number of trips.

2.

TIA Requirement

A TIA is required to be submitted for City approval at the time of platting and/or site plan review for those developments that are expected to meet any traffic threshold level of change described below. The City reserves the right to require a TIA for land developments that do not meet the threshold requirements, but may impact a sensitive area with traffic issues or may be a known public concern.

• More than 100 Peak Hour Trip (PHT) generation

• More than 5,000 vehicle trips per day generation

• More than 100 acres of property is involved

• Any changes or alterations to the Cibolo Future Thoroughfare Plan

• Land uses that have unusually high traffic generation, or fleet vehicle, characteristics.

a.

In the event that a land development project, for which a TIA is required under this Section, is not completed within five (5) years from the date of submission of the TIA to the City, the TIA shall expire, and a new TIA shall be required, and the completion of the development project shall be analyzed based on the new TIA. For phased land projects, where the time to build out all phases exceeds five (5) years, an interim phase that occurs prior to the five year (5) expiration of a TIA shall be analyzed based on the existing TIA; however, phases that shall be completed after the five year (5) expiration of a TIA shall be analyzed based on the new TIA.

Note: For the purposes of Texas Local Government Code Chapter 245, a TIA submission to the City is a permit submission and TIA'S expire five (5) years after such submission.

3.

TIA Responsibility

The primary responsibility for assessing the traffic impacts associated with a proposed development rests with the applicant. The City serves in a review capacity for this process. Both the City and the developer share responsibility to consider all reasonable solutions in the mitigation of transportation problems identified through the study process. The TIA must be prepared, signed and sealed by a professional engineer registered to practice in Texas, with experience in Transportation Engineering sufficient to assess traffic impacts.

4.

Compliance with Cibolo Design and Construction Manual

A TIA shall be completed in accordance with all TIA requirements specified in the Cibolo Design and Construction Manual.

5.

TIA Scope Assessment

Prior to the submittal of any TIA, the developer, or the Civil or Traffic Engineer representing the developer, shall meet with the City Engineer, or his duly authorized agent, to formally determine the scope of the TIA. The scope of the TIA shall be sufficiently scaled to reflect the traffic impact of the proposed use that is causing the TIA to be submitted and may include pedestrian and bicycle elements depending on the nature and location of the proposed use(s). Once the scope of the TIA is established, the City Engineer, or his agent, shall formally stipulate said scope in writing. The City Engineer reserves the right to expand, or to contract, the scope of the TIA as additional details about the proposed use(s) causing the TIA to be prepared is ascertained, provided that such an expansion of scope is based on sound generally accepted traffic engineering practices.

6.

TIA Threshold Analysis

In order to determine when a TIA is required, the TIA Threshold Analysis worksheet listed as Table 18.1 (PG. 233 of this UDC) shall be utilized.

7.

TIA Review

The TIA shall be reviewed by the City Engineer and any other necessary review authorities. Review comments shall be provided to the applicant for response. Response by the applicant shall be in the form of a letter, technical memorandum, or other appropriate document. The applicant shall submit final copies of the TIA to the City Engineer containing all modifications prior to final approval of the application for which the TIA was conducted.

8.

City Assistance in Development

During the course of providing for improvements, the City may cooperate with the developer in the use of its governmental powers to assist in the timely and cost effective implementation of improvements. Assistance shall not mean financial aid in actual easement acquisition, construction or engineering costs. Specifically, the City may agree to the following forms of assistance:

a.

Assist in the acquisition of necessary right-of-way and easements;

b.

Assist in the relocation of utilities;

c.

Assist in obtaining approvals from applicable County entities;

d.

Assist in obtaining approvals from TxDOT;

e.

Enter into Public Improvement Agreements as consideration in lieu of impact fees; and

f.

Assist in securing financial participation for major street improvements from applicable County entities, TxDOT or the Metropolitan Planning Organization.

9.

TIA Revisions

It is recognized that the scope of the developer's plans may change from time to time. The monitoring reports may also demonstrate changes in the area street conditions and travel patterns within and around the City. Periodic updates to the TIA may be required to address these issues and identify changes to the level of service at study intersections and streets. These updates shall address modifications to the magnitude and timing of improvements recommended by the original TIA. Any TIA amendments must be acceptable to the City, and TxDOT, when applicable.

10.

Off-Site Improvements

Based on the results of a TIA, and in those instances where the City believes public safety is at risk, the property owner shall make improvements to off-site collector and arterial streets and intersections necessary to mitigate traffic impacts generated by the development or in conjunction with related developments; with said improvements being roughly proportional to the impact of the proposed development. The City may participate in the costs of oversize improvements with the property owner as set out herein, and subject to the City's cost participation policies on oversized improvements.

11.

Construction Easements

Construction easements, in addition to rights-of-way, may be required when adequate width for streets and/or utilities is not available.

12.

Intersection Improvements and Traffic Control Devices .

Intersection improvements and traffic control devices shall be installed as may be required by the City based on the recommendations of an approved TIA for traffic safety and efficiency. Construction and design standards shall be in accordance with Cibolo Design and Construction Manual.

Table 18.1

13.

Mitigation Improvements and Roughly Proportionate Determination

A.

The purpose of the TIA is to identify if any mitigation improvements are necessitated by and attributable to the proposed development. Required mitigation improvements may include the following:

1.

Implementation of the Future Thoroughfare Plan; including right-of-way dedication (right-of-way dedication value shall be determined using the most recent appraisal district land values) and/or construction in accordance with the Cibolo Design and Construction Manual.

2.

Improvements identified by the TIA based on peak hour trip generation data, turn lane assessment and traffic impact analysis.

3.

Other improvements may include, but are not limited to, pavement widening, turn lanes, median islands, access controls, curbs, sidewalks, traffic signalization, traffic signing and pavement markings.

4.

Improvements to the TxDOT right-of-way required by the city, including right-of-way dedication, as approved by TxDOT.

Minimum Areas to be addressed in Roughly Proportionate Determination

Right-of-way dedication for adjacent exterior streets

Improvements to substandard streets

Projecting streets

Right-of-way dedication and construction of Future Thoroughfare Plan streets

Dedication of arterial or major collector streets

Upgrade existing traffic signals

New traffic signal construction

Other improvements identified in the TIA

Right-of-way dedication and construction of left and/or right turn lanes

 

B.

For phased development projects, implementation of the mitigation improvements must be completed no later than the completion of the project phase for which the TIA shows it was required. Plats for project phases subsequent to a phase for which a mitigation improvement is required may be approved only if the mitigation improvements are completed or bonded by the developer.

C.

Following the identification of mitigation improvements and any other improvements necessitated by and attributable to the development, the applicant shall utilize the methodology developed and approved by the city to determine if the mitigation improvements identified are roughly proportionate to the impact of the proposed development.

1.

At the conclusion of the TIA, the applicant will summarize all of the mitigation improvements identified in the TIA and the approximate total cost of all mitigation improvements including design, engineering and construction. Mitigation improvements that only serve the proposed development (such as site plan related recommendations and right-turn lanes into and out of a development) that provide minimal benefits to the study area roadway network shall not be included in the cost of the mitigation improvements (when compared to the maximum amount of improvements attributable to the proposed development).

2.

The applicant will utilize the approved methodology made available by the city to determine the maximum amount of improvements (measured in dollars) that may be attributable to the proposed development.

3.

The applicant shall then compare the cost of the mitigation improvements to the maximum probable amount of improvements that may be attributable to the development.

a.

If the cost of the mitigation improvements is less than or equal to the maximum amount of improvements that may be attributable to the development, then the mitigation improvements identified in the traffic impact analysis are said to be roughly proportionate to the impact of the development.

b.

If the cost of the mitigation improvements is greater than the maximum amount of improvements that may be attributable to the development, then the mitigation improvements identified in the traffic impact analysis are limited to an amount roughly equal to the maximum amount of improvements that may be attributable to the development.

4.

The methodology utilized by the city shall be as follows. The maximum amount of improvements attributable to a development is roughly proportional to the demand created by a development. This value shall be determined (measured in dollars) by multiplying the following values together:

a.

Intensity of the development (using independent variable identified in the ITE Trip Generation Manual, e.g. number of dwelling units, number of one thousand (1,000) square feet of leasable floor area, etc.);

b.

Number of vehicles—the peak hour trip generation rate for the applicable peak hour (from the most current version of the ITE Trip Generation Manual Information);

c.

Length of the trip—the anticipated trip length to/from the development on the city's thoroughfare network (a minimum value of 1.0 miles and a maximum value of 1.5 miles shall apply); and

d.

Cost per vehicle-mile—the average cost per vehicle-mile for the City to deliver a typical roadway capacity improvement project based upon the current City Engineer estimates. The Average Unit Price List shall be reviewed by the City Engineer on a regular basis to ensure the Average Unit Price List is consistent with current construction costs.

5.

The methodology shall be reviewed by the City Engineer on a regular basis to ensure the methodology is consistent with current construction costs and engineering criteria.

6.

Projects in a valid master development plan or planned unit development where mitigation improvements have been previously constructed at the cost of the applicant shall receive credit for these improvements. The credit for improvements shall be determined using the cost of the improvements at the time they were constructed. This value shall be included with the total cost of the mitigation improvements required to serve the development. The land uses previously constructed or planned for shall also be included in the calculation of the maximum probable amount of improvements that may be attributable to the development.

D.

Limitations on Traffic Impact Mitigation . Limitations on traffic impact mitigation requirements are as follows:

1.

Improvements that have been planned and funded through a capital improvement project that exceed the proposed mitigation measures recommended in the TIA are not required. The capital improvement must be planned to be awarded to a contractor for construction within one (1) year following the completion of the project phase requiring the improvement to be considered as a mitigation improvement.

E.

Exemptions . The city finds and determines that certain factors, such as interconnected street systems, mixed uses, and the availability of pedestrian facilities, can result in fewer trips than isolated, low-density subdivisions. Certain development patterns produce fewer trips and shorter trips than developments subject to conventional zoning or located on the fringe of the metropolitan area. The city hereby finds that traffic patterns and infrastructure within its urban core are established, and that there is a strong public policy to encourage reinvestment in the city's downtown areas. Further, the city hereby finds that there is a strong public policy to encourage infill development and that there is little opportunity to expand transportation capacity in many infill areas without destroying the city's historic built environment. Accordingly, the Old Town Overlay zoning district is exempt from the provisions of this section.