City of San Antonio UDC Changes to Traffic Impact Analysis (TIA) Requirements

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City of San Antonio UDC Changes to Traffic Impact
Analysis (TIA) Requirements
September 30, 2009 South Texas ITE Meeting
Kerri M. Collins, P.E., PTOE Pape-Dawson
Engineers, Inc.
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What is the purpose of a TIA?

• Identify traffic impacts associated with a
  specific development and identify mitigation
  measures that address those impacts.

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What value does a TIA provide to the developer?

• project approvals per UDC
• Identifies traffic problems.
• Establishes basis for developers obligation for
  improvements.
• Identifies future transportation needs.

The Rim
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Ordinance 2009-05-21-0429

• The developer will bear a portion of the costs
  of municipal infrastructure improvements in an
  amount that is roughly proportionate to the
  proposed development.

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Proportionality Spreadsheet

• Provided by the City.
• Updated by the City.
• Establishes maximum financial obligation
  developer must contribute towards mitigation of
  traffic impacts.
• Can be challenged in appeal process.
• TIA identifies impacts, mitigation improvements
  and cost.

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Proportionality Spreadsheet Examples

• 14,000 SF Pharmacy -
• up to 200,000
• 3,500 SF Fast Food Restaurant up to 195,000
  
• 100,000 SF Retail
• up to 800,000
• 80,000 SF Supermarket
• up to 1.75 Million
• 500 Unit Apartment Complex -
• up to 1 Million
• 500 Single Family Homes
• up to 1.6 Million

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Its Not Just a TIA Anymore

• TIA Proportional Mitigation Determination
  Report are required for Applications for MDP,
  Permitting, Rezoning when any of the following
  applies
• Project generates 76 or more PHT
• Change to existing TIA or existing zoning results
  in increase of 76 or more PHT or 10 of total pk
  hr trips
• Building permit submission shows 5 or more
  increase in PHT compared with TIA
• TIA is over 5 years old
• Access points in original TIA are reduced or
  relocated.

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When is a TIA Required?

• Today
• If 100 peak hour trips TIA Worksheet
• If 101 to 500 peak hour trips Level 1 TIA
• If 501 to 1,000 peak hour trips Level 2 TIA
• If gt 1,000 peak hour trips Level 3 TIA

• On March 1, 2010
• If 75 peak hour trips or less TIA Form w/Turn
  Lane Evaluation Required
• If 76 peak hour trips or more TIA is required.

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A Study Level TIA is Needed for

• A site that is gt 500 Acres and
• An application is being made for an MDP or PUD

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Density/Land Use Thresholds
Land Use Today Level 1 TIA March 1, 2010 Full TIA
Land Use Density for 500 Peak Hr Trips Density for Over 75 Peak Hr Trips
Single Family Homes 490 units 75 units
General Office 300,000 SF 50,000 SF
Retail 125,000 SF 20,000 SF
Fast Food Restaurant 10,000 SF 1,800 SF
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TIA Study Area per UDC

• Today...

• As of March 1, 2010 ...

Category Impact Area
Any TIA 1.5-mile distance from site boundary. Measured along road network.
Category Impact Area
Level 1 or 2 TIA ¼ mile radius from site boundary.
Level 2 TIA up to a maximum of 1-mile radius.
Level 3 TIA 1-mile radius from site boundary.
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Intersections Are Included if Both Conditions Are
True

• 76 or more peak hour trips entering or exiting
  the intersection and
• the intersection is within 1.5 miles of the site
  boundary, measured along the road network.

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Study Intersections
250
250
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Other Relevant Changes

• Peak hours Can be AM, PM, Midday, Afternoon,
  Saturday, depending on type of use.
• Project Phasing maximum of 7 years per phase.
• TIA Scoping Meeting with Development Services and
  Public Works is required to review assumptions
• Trip generation, distribution assignment.
• Study area and intersections
• Pass-by/Internal Trip Credits
• Peak hours
• Analysis Scenarios

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How do we measure an impact?

• We compare the No Build Condition results to the
  Build Condition results.

Traffic generated by this project
Measurement of Impacts
Traffic from other nearby projects and population
growth
Existing traffic
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Impact Definition for Study Intersections

• Today
• for intersections in site and along boundary
  must improve to No Build LOS if Build LOS is D,
  E, or F.

• March 1, 2010
• for ALL signalized study intersections must
  maintain No Build LOS C or improve to within 20
  of No Build delay if Build LOS is D, E, or F.

• March 1, 2010
• for unsignalized intersections must maintain
  No Build LOS C or improve to within 10 of No
  Build delay if Build LOS is D, E, or F.

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Mitigation Measures

• Today
• improvements for intersections in site and along
  boundary only. If No Build is LOS F, no
  mitigation required.

• March 1, 2010
• improvements at intersections with impacts
  both on and off-site.
• if improvements are deemed infeasible then
  non-compliant intersection.

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Additional Submission Requirements

• Rough Proportionality Spreadsheet
• Approximate total cost of improvements including
  design, engineering and construction to be
  provided in the TIA.

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TIA Content Requirements

• Detailed content per Section 35-B122.
• Saturday peak hour analysis must be included for
  retail use or weekend generator.
• Land uses with peaks outside of weekday AM, PM
  should be included, i.e., schools.
• Seasonal adjustment factor must be applied to
  count data collected during non-school periods.
• Separate trip distributions for land uses with
  different travel patterns. i.e., retail vs.
  office/residential.

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Turn Lane Requirements

• Today
• Right and left-turn lanes required at site
  access points with 60 peak hour entering right or
  left-turn vehicles.

• March 1, 2010
• Requirement is 50 peak hour or 500 daily right or
  left-turn vehicles.
• If median, left-turn bay required regardless of
  left-turn volume.
• Turn lanes are required where safety issue is
  present.

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Turn Bay Design

• Prior UDC
• Not defined

• As of August 20, 2009
• Design should be in accordance with TxDOT design
  manual for minimum taper and storage length.
• Deceleration length to be determined by either
  method
• TxDOT Design Manual 20 mph differential speed
  from roadway design speed. or
• Calculation of stopping sight distance based on
  design topographic conditions and differential
  speed of 10 mph.

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Median Spacing Requirements

• Prior UDC
• 400 spacing between median openings.

• As of August 20, 2009
• Arterial from freeway 660 from the intersection
  
• Arterial to Arterial 500 from the intersection
  and 400 thereafter
• Freeway/Arterial to Collector 400 from
  intersection and 400 thereafter

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Intersection Spacing

• Prior UDC
• Centerline offset minimum of 125

• As of January 15, 2009
• Local A with Local A 125 centerline offset.
• Streets intersecting with a collector 150
  centerline offset or minimum distance needed for
  turn lane.
• Collector with Collector 200 centerline offset
  or minimum distance needed for turn lane.
• Collector with Arterial 400 centerline offset
  or minimum distance needed for turn lane.

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What is the Traffic Engineers role?

• To foster transportation solutions that meet the
  requirements of the public agency, that adhere to
  acceptable engineering standards and do not
  exceed the obligation required of the developer.
• Develop solutions in the best interest of the
  client and public

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Questions?