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El Paso Pre-Analysis Consensus Plan for Transportation Conformity MTP 2030

March 17, 2003

The El Paso Metropolitan Planning Organization (MPO) is submitting the following outline of the assumptions, information, and methodology to be used in the conformity analysis for the 2030 El Paso MTP. This plan is being submitted to the interagency consultation partners for soliciting consensus before commencement of a full-scale transportation conformity analysis. The plan may be revised as the MPO proceeds with the analysis. Notification of such changes will be made to the interagency consultation partners.

A conformity analysis will be prepared to address the ozone, CO, and PM-10 nonattainment areas of El Paso County, Texas, and the Southern Doña Ana County, New Mexico Ozone Nonattainment Area. The pollutants in El Paso County will be tested against the corresponding budgets, while the Doña Ana County conformity test will be performed using a build/no-build or other test appropriate for a marginal ozone nonattainment area.

Metropolitan Transportation Plan/Transportation Improvement Program

MTP year: 2030
TIP years: 2004-2008

Demographic Assumptions

  1. Population

    The El Paso MPO prepared base population projections by Transportation Analysis Zone (TAZ) in cooperation with the City of El Paso Dept. of Planning, Research and Development (DPRD). El Paso County control totals were prepared by the University of Texas at El Paso using an econometric model to develop projections through 2030. New Mexico projections were prepared with the help of a panel of experts organized by the El Paso MPO for the 2020 MTP, and have been updated and revised for the 2025 and 2030 MTPs. MPO staff is preparing individual TAZ household and population projections based on the known growth trends between 1990 and 2000. The trends are fed into an integrated autoregressive-moving average (ARIMA) model, giving a projection for each zone in 2005. The 2005 figures are then adjusted as necessary to more closely match the previous land use trends developed for the 2025 MTP. The total figures for all zones will match the figures in the econometric forecast for El Paso County, and will follow the growth trend established by the panel of experts for Doña Ana County. Once figures are established for 2005, these numbers are used to make another projection to 2015, with the same adjustments made as previously described. The process will be repeated through the 2030 target year. The 2030 MTP shows an important trend that was not reflected in the 2025 MTP due to the fact that the 2025 MTP was completed before the 2000 Census was published. That trend is that almost all of the established neighborhoods are showing a decreased household size, and thus a loss of population if no new households are being added to a TAZ. While the central area of El Paso had a lower population than had previously been projected by the 2025 MTP, the areas outside the city limits showed a larger growth than had previously been projected.

  2. Employment

    Employment for the 2030 MTP will be based on the projections developed for the 2025 MTP, with adjustments. Base year employment estimates were based on county estimates from the Texas Workforce Commission for each employment sector in 1997. Projections were prepared in cooperation with the City of El Paso DPRD. Control totals for projection years will follow the same trends as in the 2025 MTP, but will be adjusted to match the totals by sector in the UTEP econometric forecast. The New Mexico projections will be the same as in the last MTP. MPO staff will extend the projections to the 2030 forecast year.

  3. Socio-Economics

    Income figures used in the travel demand model will be the same as in the 2025 MTP, and are based on block group figures from the 1990 Census. Household income figures for future years do not include any inflation adjustments. However, some TAZ income figures were adjusted in future years due to projected land use characteristics, such as expected new housing developments. All projected income figures will be in constant 1990 dollars, since the 2000 Census figures are not yet available.

  4. Land Use Model


Nonattainment Status

Affected Area: El Paso County
Attainment Date: 1999
Exemption: Section 818 of the 1990 FCAA Amendments. This incorporates a new Section 179B.
Affected Area: A portion of the City of El Paso, south of IH-10, extending approximately from the Union Station on the west to Ascarate Park on the east.
Attainment Date: 1996
Exemption: Section 818 (179B).
Affected Area: City of El Paso
Attainment Date: November 1994
Exemption: None
Ozone (Sunland Park)
Affected Area: A portion of Dona Ana County including Sunland Park, Santa Teresa, La Union, and extending north to Gadsden High School.
Attainment Date: 1995
Exemption: None

Model Assumptions

Validation year: 1997

Modal Split/Mode Choice: The modal split for 1, 2, and 3+ passenger vehicle use and transit ridership will be accomplished through the travel demand model, using a nested logit model.

VMT Adjustments: Pending HPMS factors from TTI

State Implementation Plan


The applicable SIP for ozone in the El Paso area is the 15% Rate-of-Progress SIP for Dallas/Fort Worth, El Paso, Beaumont/Port Arthur, and Houston/Galveston Ozone Nonattainment Areas. The current revision to this SIP was published July 24, 1996. Included in this document is the El Paso Section 818 Attainment Demonstration.

Motor vehicle emissions budgets for ozone were established by a letter from Mr. Thomas Diggs, Chief Air Planning Section, U.S. EPA to Mr. Roy Gilyard, Executive Director, El Paso MPO, June 11, 1999:

VOC: 36.23 tons/day
NOx: 39.76 tons/day

Carbon Monoxide

The SIP for carbon monoxide (CO) was revised September 1995. The motor vehicle emissions budget was established by a letter from Mr. Robert E. Hannesschlager, P.E. Acting Director, Multimedia Planning and Permitting Division to Mr. Jeffery A. Saitas, P.E. Executive Director, TNRCC, Sep. 1, 1999.

CO: 96.90 tons/day


The motor vehicle emissions budget for particulate matter (PM-10) was established by a letter from Thomas H. Diggs, Chief Air Planning Section, U.S. EPA to Peter A. Lombard, Director Office of Planning and Program Development, Jan. 28, 1997.

PM-10: 12.10 tons/day

Control Strategies

The following SIP mandated measures will result in emission reduction credits.

Strategy Methodology Ozone CO PM-10
a. I/M Program1 MOBILE X    
b. Reformulated Gasoline MOBILE X    
c. Oxygenated Fuels MOBILE   X  
d. Alley Paving2 PART5     X
e. Street Sweeping2 PART5     X


1. The I/M SIP was revised in October 2001 (see "Revisions to the State Implementation Plan (SIP) for the Control of Ozone Air Pollution, Inspection/Maintenance SIP for Dallas/Fort Worth, El Paso, and Houston/Galveston Ozone Nonattainment Areas," TNRCC, October 24, 2001). This revision to the SIP & Rules modified the vehicle I/M program which required all vehicle emissions test stations in the Dallas/Fort Worth (DFW) and Houston/Galveston (HGA) program areas, with the exception of low volume stations, to offer both acceleration simulation mode (ASM-2) testing and onboard diagnostics (OBD) testing to the public, and required all vehicle emissions test stations in the El Paso (ELP) program area to offer both two-speed idle (TSI) testing and OBD testing to the public. The rule required El Paso to continue TSI testing through December 31, 2002. The rule also required, beginning January 1, 2003, that all 1996 and newer model year vehicles equipped with OBD systems be tested using United States Environmental Protection Agency (EPA)-approved OBD test procedures and all pre-1996 model year vehicles be tested using TSI test procedures. In addition, the rule required all inspection stations to offer both TSI and OBD tests beginning January 1, 2003. On September 13, 2002, TCEQ proposed a rule change to revise the El Paso I/M program to convert on-board diagnostic testing from a requirement beginning January 1, 2003 to a contingency measure of the El Paso ozone SIP in support of the maintenance of the ozone national ambient air quality standard. If the El Paso area violates the ozone standard, the commission will publish notification in the Texas Register of its determination that the contingency measure will be implemented. The OBD testing will be required to begin 12 months after the notice is published in the Texas Register. The rule was adopted on December 4, 2002 (see "Revisions to the State Implementation Plan (SIP) for the Control of Ozone Air Pollution, Inspection/Maintenance SIP for Dallas/Fort Worth, El Paso, and Houston/Galveston Ozone Nonattainment Areas," TCEQ, December 4, 2002). Emissions in the MOBILE model exclude the reductions that would have occurred with OBD testing.

2. A Memorandum of Agreement (MOA) between TNRCC and the City of El Paso was approved on October 9, 2001 concerning the paving of unpaved streets and alleys and sweeping of streets. The MOA was signed by the Mayor of El Paso and Jeffrey Saitas, Executive Director of TNRCC (now TCEQ). The MOA remains in effect until August 31, 2003, and will be automatically renewed on an annual basis unless one of the parties provides written notice. The MOA states that TNRCC submitted and EPA approved the El Paso PM-10 SIP revisions in 1991 with a MOU between TNRCC and the City of El Paso as an attachment concerning paving of unpaved streets and alleys and semi-annual sweeping of streets. The initial MOU was developed after the public comment period because of a suggestion from EPA that an MOU was needed to ensure a commitment of funds for the paving of roads and construction in the event of city budget cuts. The MOA was developed to include measures that will be taken to implement the goals of the SIP, i.e. paving unpaved streets and alleys and providing regular street sweeping of all streets. The City has agreed to perform alternative measures to the requirements of the SIP (such as paving 15 miles of alleys per year). The MOA provides a more effective and appropriate manner to implement the intent of the SIP. It is the intent of the parties to incorporate the MOA into the PM SIP.

Mobile Source Emission Reduction Strategies

Transportation Control Measures (TCMs)

The El Paso MPO will not use a direct modeling or post-processed model approach to take emissions credits for TCMs due to that fact that the model results are anticipated to demonstrate attainment for the MVEB's without the additional calculations. However, estimated emissions benefits from the TCMs are included in the following tables, and will be included in the conformity report.

1985 TCMs

The following TCMs were adopted by the EPUTS Policy Advisory Committee in February 1985 and were incorporated in the SIP for Air Quality for El Paso County in 1987. These TCMs are not modeled for additional emissions credits in the conformity analysis. However, estimates of emissions reductions (in tons/year) are included in the table below:

Strategy VOC NOx CO Source
a. Carpool (Rideshare) Program 3.60 3.71 30.03 Rideshare software CRIS, Sep 2000
b. Traffic Control System (Interconnect 124 signalized intersections) 90.00   1,389.00 Original estimate 1985
c. Nine Highway Improvements 66.50   849.00 Original estimate 1987
d. Public Transit Improvements (Reduce road calls from 4,818 to 1,500 per year)       N/A

TCMs from the 1996 Ozone Rate-of-Progress SIP

The following TCMs are listed in Revisions to the State Implementation Plan (SIP) for the Control of Ozone Air Pollution - 1996 15% Rate-of-Progress SIP. Emission benefits were calculated for each of the intermediate and horizon years using post-processed methodology.

TCM Emissions Benefits 2005 (Tons/Year)
Strategy VOC NOx CO
a. Northeast Transit Terminal 0.35 0.49 2.66
b. Freeway Management System 62.33 4.59 584.59
c. CNG Fueling Facility (Sun Metro) 1.95 9.22 9.55
TCM Emissions Benefits 2015 (Tons/Year)
Strategy VOC NOx CO
a. Northeast Transit Terminal 0.30 0.49 2.37
b. Freeway Management System 103.89 7.99 1,052.00
c. CNG Fueling Facility (Sun Metro) 1.92 7.51 9.46
TCM Emissions Benefits 2020 (Tons/Year)
Strategy VOC NOx CO
a. Northeast Transit Terminal 0.29 0.49 2.46
b. Freeway Management System 103.09 8.00 1,054.39
c. CNG Fueling Facility (Sun Metro) 1.92 7.43 9.46


The El Paso MPO will use the following MOBILE model input parameters in the conformity analysis.

Parameter Details Data Source
a. Emission Model Version: MOBILE6, PART5 EPA
b. Emission Model Runs: Years 2005, 2015, 2025, 2030  
c. Time Periods: Estimated hourly figures derived from 24-hour assignments PREPIN software, TTI
d. Pollutants Reported: VOC, NOx, CO, PM-10 MOBILE6, PART5
e. Calendar Dates: Summer (July 1) and Winter (Nov 1)  
f. Functional Class: 14 functional classifications, divided into two capacity parameters (high and low) for the volume/delay equation parameters TTI
g. Speed Model Formulation: Uses volume/delay equation with the delay model parameters developed for the Dallas/Fort Worth area TTI
h. Area Specifications: 11 area types: 9 in Texas, 2 in N. M. TTI

Project Listings

A roadway listing, including all projects that change roadway capacity (new roads, widenings, roadway removals, etc.) will be provided in addition to the following:

CMAQ Projects

The El Paso MPO will include a spreadsheet in the conformity document showing status of funded CMAQ projects, including, emission reductions for each project, amount of funding for each project, and implementation dates.

Non-Federal Projects

The 2025 MTP and its revisions identified all projects that do not receive federal funding (local initiatives, private ventures, etc.). The 2030 MTP makes no changes to this list, but will review the projects included in the 2005 network according to the latest construction estimates and information provided by local agencies.

Exempt Projects

The El Paso MPO will identify exempt projects in the TIP according to the specifications outlined in the Conformity Regulations (93.126).

Updated: 07/06/2011
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