August 6, 2002

 

 

 

The Honorable Jim Jeffords

United States Senate

Chairman

Committee on Environment and Public Works

Washington, DC  20510-6175

 

Dear Chairman Jeffords:

 

This letter is in response to a request made by the Committee on Environment and Public Works of the United States Senate, dated July 3, 2002, regarding our experience with the Clean Air Act conformity program and transportation control measures, and the impact these have had on our transportation and air quality efforts.  Attached you will find responses to the series of specific questions that were transmitted to us.

 

We appreciate the opportunity to provide input on the reauthorization of the Transportation Equity Act for the 21st Century process.  If I can be of further assistance on this subject matter, I can be reached at (817) 695-9240.

 

 

                          Sincerely,

 

 

 

                          Michael Morris, P.E.

                          Director of Transportation

 

CK:baw

Attachment

 

cc: Fred Abousleman, National Association of Regional Councils

      Delania Hardy, Association of Metropolitan Planning Organizations

      James Shrouds, Federal Highway Administration

      Chuck Mueller, Texas Natural Resource Conservation Commission

      Steve Simmons, P.E., Texas Department of Transportation

      2001-2002 UPWP Element 3.02 Project File

Difference in Timing of Schedules

 

Describe how the different schedules for the SIP, TIP, conformity, etc. and the impacts of data changes on out year emissions affect your ability to develop effective and timely transportation and air quality plans.  Provide a time-line or narrative description of your various schedules.

 

The differences of the schedules for the SIP, TIP, Metropolitan Transportation Plan (MTP), and Conformity are varied and can come without warning.  For the Dallas-Fort Worth Metropolitan Planning Organization (MPO), the MTP is usually prepared every three years, consistent with federal rules.  However, SIP or TIP influences could trigger a new MTP out of sequence.  As a result, a new conformity analysis is required.  As highlighted in Table 1, the MPO decided a MTP Update was required in 2001 (less than a year after receiving federal approval on a similar effort) to ensure a three-year MTP cycle due to a SIP schedule that would establish new motor vehicle emission budgets (MVEBs) and conformity.

                       

A new TIP is developed every year due to the number of transportation projects being planned.  This is above the typical two-year cycle.  As a result, a new conformity analysis is required.  However, due to Tier II regulatory language contained in our applicable SIP, the region is unable to perform a necessary conformity analysis on the TIP in 2003, therefore our TIP schedule, and associative conformity analysis, changed to make TIP modifications prior and after our freeze (see Table 1). 

 

TABLE 1

 

DALLAS-FORT WORTH METROPOLITAN PLANNING ORGANIZATION

TRANSPORTATION PLANNING DOCUMENT SCHEDULES

Current Schedules

Year

SIP

(as needed or attainment date)

MTP

(every three years)

TIP

(every two years)

Conformity

(used to measure SIP, TIP and MTP)

1997

 

Ö

Ö

Ö

1998

 

 

Ö

Ö

1999

Ö

 

Ö

Ö

2000

 

Ö

 

Ö

2001

 

Ö*

Ö

Ö

2002

 

 

Ö

Ö

2003

 

 

 

 

2004

Ö

Ö

Ö

Ö

2005

 

 

Ö

Ö

2006

 

 

 

 

2007

 

Ö

Ö

Ö

* MTP Update required to ensure three-year cycle maintained as result of new SIP 2004

 

These conflicting schedules hinder a region’s ability to appropriately implement policies, programs, and projects in a Plan or TIP as planning documents continue to be the focus.  In addition, differences in timing of schedules and premature adjustments to schedules impede development of an out year strategic milestone calendar, sending confusion to our regional partners and resource agencies as they try to incorporate their planning activities to these federal obligations.

 

 

What impact have these schedules had on investments in highway and safety projects, construction costs, and air quality projects and activities?

 

The timely implementation of transportation projects and programs are of high priority.  Therefore, to avoid impacts, schedules of the TIP and MTP are often adjusted, within the limits allowed by regulations, to ensure that projects and programs that are ready for implementation can proceed.  However, SIP-related requirements are often out of sync with the TIP and MTP and have the potential to cause TIP and MTP modification freezes due to the inability to perform an air quality conformity analysis.  This could cause recommended projects from being able to proceed because they may be inconsistent with TIP or MTP.  Unnecessary delays could cause construction costs to increase and have a negative impact on air quality if projects cannot be implemented as expected.  Generally, more time is spent on replanning already approved plans than working on the implementation of specific projects.  Greater focus on mobility and air quality project delivery is necessary.

 

 

What has been your experience coordinating your SIP and conformity processes with SIP submittals or updates?

 

Keeping in mind the varying schedules with SIPs and conformity associated to a MTP and TIP, experiences in coordinating among these elements have been a challenging process in the Dallas-Fort Worth Metropolitan Area.  This can be attributed to coordinating a MTP that has a three-year update cycle, a TIP that has a two-year update cycle, and a SIP submittal process influenced by real-time observed air quality data. 

 

As experienced in the DFW area, a SIP submittal can introduce regulatory language that would require changing air quality conformity schedules of a MTP and TIP.  An example is the Environmental Protection Agency’s (EPA) position with regards to use of Tier II automobile standards in the MOBILE5 emission factor model.  This situation required the region to take a step back in its implementation of policies, programs, and projects and reissue multiple planning activities.

 

 

MOBILE6 Versus MOBILE5 Projections

 

Compare and contrast your MOBILE5 and MOBILE6 emission projections.

 

In the fall of 2001, the EPA sponsored a study to evaluate the differences of MOBILE5 and MOBILE6 using local data from the Dallas-Fort Worth region.  Although a final report has not yet been published, draft reports indicate an increase in MOBILE6 projected Volatile Organic Compounds (VOC) and Nitrogen Oxides (NOx) of up to 50 percent over MOBILE5.  After approximately 2008, projected emissions are similar between MOBILE6 and MOBILE5.  This

significant trend continues to occur into the future where we see MOBILE6 emissions well below those of MOBILE5 emissions.  These trends are consistent with national research performed on MOBILE6 versus MOBILE5. 

 

 

How does the increase in near term emissions (through 2010) from MOBILE6 affect your conformity status?

 

Due to the significant differences in near term emissions between the two emission factor models, it would be extremely difficult for a region to pass a conformity analysis using MOBILE6 against SIP motor vehicle emissions budgets previously developed with MOBILE5.  Since this is an obvious analysis mismatch, the Dallas-Fort Worth nonattainment area has planned its schedules accordingly to avoid such an evaluation (as noted in the Differences in Timing of Schedules responses above).  The proper method, which is included in our mid-course review, is to recalibrate the air chemistry model with the new MOBILE6 emission software and reforecast the emissions permitted in a demonstration of attainment (i.e., higher emission do not necessarily mean a SIP or conformity analysis would not be successful.)

 

 

How will your air quality planning process take the new MOBILE6 into account, and will the SIP be updated before or after the new MOBILE6 projections?

 

As part of the Dallas-Fort Worth SIP submittal in April 2000, a mid-course SIP review is committed to EPA by May 2004.  Within this process, MOBILE6 emission projections will be incorporated into an air chemistry model through new on-road mobile source emission inventories.  This modeling process will establish MOBILE6 derived motor vehicle emissions budgets for the nonattainment area for use in an air quality conformity analysis scheduled in 2004. 

 

 

Will the new 8-hour NAAQS likely lead to an increase or decrease in your vehicle emissions budget?

 

As an example, if more on-road mobile emission reductions are necessary to ultimately meet the 8-hour standard, then it could be assumed the resulting motor vehicle emissions budgets will decrease.  More information will be available through a comprehensive emissions analysis following final rules.  A different mix of controls may be necessary to meet an 8-hour standard, which are not well understood today (e.g. role of VOC emissions.)

 

 

Additional Vehicle Emission Controls

 

What additional existing controls could be implemented in your area to significantly reduce vehicle emissions, e.g., inspection and maintenance, reformulated fuels, diesel retrofit, TCMs?

 

Having just completed a comprehensive and technical review of on-road mobile control strategies for the Dallas-Fort Worth SIP, there is no other existing control strategy to significantly reduce vehicle emissions that could be feasibly implemented in the region.  As we continue to seek or develop additional controls, we keep in mind the main elements of on-road mobile emissions; cold starts, pre 10 a.m. emissions, hard acceleration, excessive idling, high emitting vehicles, diesel engines, low speeds, excessive speeds.  Another approach to reduce vehicular emissions is to advance already existing federal gasoline, diesel, and engine standards earlier than required.  One has to remember that Dallas-Fort Worth is already implementing an aggressive high-emitting vehicle program, freeway management curriculum for fire and police, vehicle speed reduction with enforcement, and sustainable development projects.

 

 

Would these controls be sufficient to address the potential increase in emissions projected under MOBILE6?

 

One cannot conclusively state that the above-mentioned measures would counter all the potential increases in emissions projected in MOBILE6, since the model is yet to be tested under Dallas-Fort Worth specific conditions and the appropriate methodology is to recalibrate the air chemistry models to determine needed emission budgets.

 

 

Role of Transportation Control Measures

 

What role do TCM’s plan in helping to meet attainment?  Please list the TCMs and CMAQ projects in your plan, and the associated "off" or "on" model emission reduction credits for each.

 

Conformity could not be certified without CMAQ funds and Transportation Control Measures (TCMs). TCMs, along with other pollution reduction strategies, have assisted the Dallas-Fort Worth region in working towards attainment by continually reducing the number of ozone exceedance days recorded in the region from 15 in 1995 to 2 in 2001.  Currently, the Dallas-Fort Worth region is under a conforming MTP that includes Intersection Improvements, Rail Projects, Bicycle and Pedestrian Facilities, High Occupancy Vehicle Lanes, Vanpools, Park and Ride Lots, and Grade Separations.  Table 2 outlines the emission reduction estimates associated with each TCM category.  Most TCMs in the plan are funded through the CMAQ Program.  Although not classified as TCMs, additional strategies utilizing CMAQ funds and included in the region’s SIP include clean vehicles, Intelligent Transportation Systems, vehicle retirement, sustainable development, and traffic signal improvements.

Table 2

 

Transportation Control Measures

Commitments

Emission Reduction Estimates (lbs/day)

Volatile Organic Compounds

Nitrogen Oxides

2007

2015

2025

2007

2015

2025

 

 

 

 

 

 

 

 

 

 

 

Intersection Improvements

 

775

 

Locations

2,306

1,450

1,293

4,635

2,420

2,150

Grade Separations (1)

 

15

 

Locations

--

--

--

--

--

--

HOV Lanes (1)

 

76

 

Miles

--

--

--

--

--

--

Park-n-Ride Lots (2)

 

8,236

 

Spaces

94

60

54

190

100

87

Pedestrian/Bicycle Facilities

 

710

 

Miles

1,140

727

649

2,290

1,202

1,046

Rail (1)

 

96.9

 

Miles

--

--

--

--

--

--

Vanpool

 

547

 

Vanpools

341

217

194

685

360

313

TOTAL (lbs/day)

 

 

 

 

3,881

2,454

2,190

7,800

4,082

3,596

TOTAL (tons/day)

 

 

 

 

1.94

1.23

1.10

3.90

2.04

1.80

(1) Emission reduction benefits have been included directly in the Dallas/Fort Worth Regional Travel Model (DFWRTM).

 

 

(2) Emission reduction benefits are both post-processed and included directly in the DFWRTM.

 

 

 

 

 

What percentage of total emission reductions do they represent?

 

TCMs amount to approximately five percent of on-road NOx emission reductions in 2007 and four percent of on-road VOC emission reductions.  Without CMAQ funding, conformity could not have been certified.

 

 

Are there CMAQ projects in your plan for which you have not applied any on or off model emissions reductions?

 

No.  All CMAQ projects have identified emission reduction credits as requested by the Texas Department of Transportation for a CMAQ Annual Report.  It should be noted that the CMAQ program has encouraged a great deal of planning and funding creativity due to different regulations impacting CMAQ and the Surface Transportation Program.  This creativity has shaped air quality policies, programs, and projects for the benefit of reaching attainment and better quality of life for each citizen.  Without innovative programming, a less aggressive air quality program would have resulted.

 

 

Impacts of Conformity Lapse

 

If your area has experienced a conformity lapse, describe the effect this has had on transportation and air quality planning, funding process, preconstruction, and construction.

 

The Dallas-Fort Worth region has not experienced a conformity lapse.

 

When projects were reactivated, after U.S. DOT approved your conformity determination, what impact did this have on funding, project completion dates, personnel, renegotiation of contracts, updating old information, etc.

 

This question does not apply to the Dallas-Fort Worth region.

 

 

What impact did the March 1999 U.S. Court of Appeals decision to eliminate the EPA "grandfather" provision from the conformity regulations have on your transportation investments?

 

The March 1999 U.S. Court of Appeals decision did not have any noticeable impact on transportation investments in the Dallas-Fort Worth region.

 

 

ROLE OF MOTOR VEHICLE EMISSION ESTIMATES AND MODELS

 

How has conformity analysis helped improve the quality of estimates of motor vehicle emissions for SIPs to better protect public health?

 

The procedure for estimating on-road mobile emissions is consistent for both the SIP and the Air Quality Conformity Analysis.  However, conducting a conformity analysis on a more frequent time scale allows for the use of latest planning assumptions and tools to better quantify vehicle emissions.  Many parameters involved in the quantification of emissions change over time such as roadway and transit networks, vehicle mix, and demographic data.  As a result, new emission estimates are actually created with each conformity analysis.  In addition, the effectiveness of control strategies, including TCMs are evaluated based upon implementation schedule and before/after studies.  The regular study of a region’s dynamics and the consequential effect on emissions better prepare an agency when it is time to develop a new SIP.  Better knowledge of vehicle emission estimates ultimately leads to better protection of public health.  This replanning effect is offset by less time actually implementing aggressive air quality strategies.

 

 

How accurate and consistent have estimates of regional motor vehicle emissions been when compared with each other over time and with actual experience?

 

Regional on-road motor vehicle emissions estimates in the Dallas-Fort Worth nonattainment area have been consistently following a decreasing trend due to the region implementing many control strategies over the past 10 years.  Specifically, significant emissions reductions are attributed to inspection and maintenance, reformulated fuels, transportation control measures, continual advances in vehicle technology, and associated vehicle fleet turnover.  Table 3 lists the official on-road mobile emission estimates for the Dallas-Fort Worth ozone nonattainment area.

TABLE 3

 

 

Dallas-Fort Worth Ozone Nonattainment Area

Motor Vehicle Emission Estimates

 

YEAR

VOC (tpd)

NOx (tpd)

1990

306.60

293.03

1996

235.00

NOx Waiver

1999

125.25

NOx Waiver

2007

75.34

149.72

 

 

How have official estimates of motor vehicle emissions in your metropolitan region changed over the past 10-20 years and how well have they tracked actual emissions in years past?

 

The overall decrease in modeled motor vehicle estimates compare well with monitor data from 1990 to 2001.  During this time period, the extents to which the monitors violate the one-hour ozone standard have steadily decreased indicating a concurrent decrease in precursor pollutants released into the atmosphere.  In comparison to observed monitored data, the highest number of exceedances recorded at any given monitor over a three-year averaging period has decreased from 12 exceedances in the 1994 to 1996 timeframe to 3 exceedances in the 1999 to 2001 timeframe. 

 

 

Role of transportation Models

 

Has conformity analysis been supported by adequate regional transportation analysis models that accurately reflect how changes in highway capacity affect total travel and air pollution emissions?

 

Yes and no.  Transportation analysis models in use today were originally developed for macro-scale level planning, not micro-scale level planning required in air chemistry modeling.  Issues include time-of-day, speeds, functional classification, vehicle miles of travel, etc.  For more information on concerns regarding existing transportation analysis models and recommendations for future models, please refer to a report published by the National Research Council; Modeling Mobile Source Emissions, 2000, National Academy of Science.  However, transportation models are more accurate than emission models (e.g., MOBILE5 vs. MOBILE6) and air chemistry models (e.g., for 20 years urban areas were told to reduce VOC emissions instead of NOx emissions.)

 

 

How well have your region’s travel models tracked actual experience with growth in vehicle miles of travel (VMT)?

 

The Dallas-Fort Worth Regional Travel Demand Model tracks vehicle miles of travel very well.  The roadway travel model calibration and validation process are major steps prior to the forecasting process to ensure the travel model replicates observed human travel behavior in the region adequately.  In the Dallas-Fort Worth region, models project 20 years backward before they are asked to project 20 years forward.

 

 

Please include an indication of how sensitive your/these models are to effects of induced traffic.

 

The travel model is sensitive to the effects of induced traffic.  It depends on your definition of induced travel.  Induced travel includes population and employment relocation, and trip length increases with freeway investments.  This travel model does this.  Route choice and time of day travel is not classified as induced travel although most models successfully address this.  The better question is how well does EPA forecast emissions and air quality models forecast ambient ozone levels accurately.  A review of the previously cited NAS document is suggested.