2019 Traffic Noise Policy - Texas A&M University · 2019. 11. 4. · ENV125 – Traffic Noise...

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2019 Short Course – Environment – New 2019 Noise Policy October 15, 2019

2019 Traffic Noise PolicyNew Noise Policy and Implementation Guidance Requirements

October 15, 2019

Table of contents

Effective Date and Overview of Changes

Acoustic Feasibility

Reasonableness – Standard and Alternate Barrier Costs

Absorptive Treatment

Reasonableness – Cost Averaging

Noise Workshop Requirements

Existing Model Validation

23-26Traffic Noise Toolkit, Training, and Conclusion8

Ch-Ch-Ch-Changes!

Streamlined - Requirements OnlyAddresses requirements outlined in

23 CFR 772 that must be specified bythe state DOT and approved by FHWA

User-friendlyGuidance, how-to instructions & examples

Can be updated without formal FHWA approval

On ToolkitFHWA Approved onDecember 31, 2018

Coming Soon toNoise Toolkit

2019 Short Course – Environment – New 2019 Noise Policy October 15, 2019 4

Is project environmentally cleared?

Does project require a Reevaluation for noise

AND/ORa Noise Workshop?

Use 2019 Noise Policy

YES Noise analysis started on or after December 31, 2019

Use either2011 Guidelines OR 2019 Noise Policy

Reevaluation or workshop started on or after December

31, 2019

Stop. No action required.

2019 Policy Goes into Effect December 31, 2019!!!!Use the 2011 Noise Guidelines or the 2019 Noise Policy?

What Changed?

Determine Need for a Traffic Noise Analysis(Type I project)

Collect Data

Determine Impact

Consider/EvaluateAbatement Measures

Measure/Model Noise Levels

Existing Levels(Field Measurement, Model,

Model Validation)

Predicted Levels(Model)

Predicted levels exceed existing by more than

10 dB(A)

Predicted levels approach, equal, or exceed the NAC

Absolute impact Relative impact

Traffic Noise Workshop(s)

• Validation of existing condition model

• Feasibility criteria• Reasonableness criteria• Cost averaging• Absorptive treatments

• Timing• Voting requirements

Changes are summarized in a Memo datedFebruary 6, 2019

(copy in Traffic Noise Toolkit)

Consider Noise Abatement for Predicted Traffic Noise Impacts

Feasibility

A noise abatement measure is notacoustically feasible unless:

the measure achieves a noise reduction of at least 5 dB(A) at greater than 50% of first-row impacted

receptorsAND

benefits a minimum of two impacted receptors.

Feasibility

No barrier analysis for a single receiver (residence, restaurant)

Must benefit at least 2 impacted receptors

Reasonableness Factors

Noise reduction design goal– at least a 7 dB(A) reduction for at least one

benefited receptor

Cost reasonableness– Standard Barrier Cost– Alternate Barrier Cost (optional)

Solicitation of Viewpoints

Cost Reasonableness – Standard Barrier Cost

2011• Less than 1,388 square feet

per benefited receptor• ($18 square foot/$25k per benefiter)

2019• Less than 1,500 square feet

per benefited receptor• ($35 square foot/$52.5k per benefiter)

Square footage allowance per benefiter Updated cost amounts behind the sqft value

Cost Reasonableness – Alternate Barrier Cost

If unusual construction is required, this cost can be accounted for with an alternate cost method….

Not cost reasonable if the Alternate Barrier Cost is

greater than two times the Standard Barrier Cost

(currently 2X = $105k per benefiting receptor)

Optional Method!

Absorptive Treatments

When the width between two parallel noise barriers is less than 10 times the barrier height, consider sound absorptive treatments to reduce acoustic reflections

<<< parallel barriers >>>consider absorptive treatment

when width:height ≤ 10:1

Reasonableness - Cost Averaging

A method to leverage more abatement for a corridor by using very cost-reasonable barriers (i.e. low square footage per benefited receptor values) to “share” the extra allowance with barriers that are not otherwise cost reasonable.

Requirements for Cost Averaging:– Square footage per benefited

receptor for each barrier is less than two times the Standard Barrier Cost criterion, AND

– Collectively, the square footage per benefited receptor for all barriers being averaged do not exceed the Standard Barrier Cost criterion

Optional Method! Contact an ENV noise SME to discuss and request a copy of the methodology

Barrier 135

benefiters

Barrier 228

benefiters

Barrier 312

benefiters

Barrier 412

benefiters

Barrier 53

benefiters

Barrier 69

benefiters

Cost averaging

Sq Ft per Benefiter“Extra” Sq Ft Exceeds Criterion

Reasonable – Solicitation of Viewpoints

Noise Workshops Must conduct at least one informative “noise workshop”

Who can vote? Send ballots to:

– all benefited receptors– non-benefited receptors that border or are directly adjacent to a proposed

abatement measure Both property owners and non-owner residents are eligible to vote

Reasonable – Solicitation of Viewpoints

PROPOSED NOISE BARRIER

-5.4 -4.6

-2.3-3.5-4.1

-6.3 -7.8 -6.3 -5.2

-5.0 -4.5 -3.7

Reasonable – Solicitation of Viewpoints (continued)

Weighted Ballot One vote allocated per residential receptor

(i.e. each house or apartment unit)

10% of vote to resident or renter (0.1 vote)90% of vote to owner (0.9 vote)

If owner-occupied, response counts as 1 vote

Tallying Votes Clarification: Failure to respond does not mean a “yes” or a “no” vote.

Approval of a noise barrier based on majority of votes RECEIVED

Reasonable – Solicitation of Viewpoints (continued)

Low Response Rate Recommend additional rounds of voting to achieve a response from a

majority of receptors If < 25% response rate after two rounds of voting, then decision made after

required consultation with ENV SMEs and TxDOT management

Re-voting Once a decision has been made, re-voting only

considered when:– An error in original noise workshop voting process– A substantial change to a proposed abatement since

the workshop– An approved barrier has not been constructed within

five years of a noise workshop, due to project delays

What is Existing Model Validation?

Required to verify the accuracy of noise model used to predict existing noise levels for the project The existing noise model is validated if measured noise levels and

predicted noise levels (from a validation model with field-collected traffic inputs) are within +/-3 dB(A).

Validation demonstrates that you have prepareda GOOD MODEL

that can predict existing noise levelsthat are reasonably accurate.

Therefore, the existing model can be updated to include the proposed design with a higher degree

of confidence.

Existing Model Validation

Select Validation Site(s)

Input Field-collected Traffic Data to

Existing Condition Validation Model

Collect Field Measurements

Coordinate with District Noise Specialist or ENV Subject Matter Expert

Sound Level MeasurementdB(A) Leq(h)

Traffic Information• Count number and

types of vehicles• Determine speed

Minimum 15-minutemeasurement period

Collect sound level measurements and traffic info simultaneously

Field-measured Sound Level

Model-calculated Sound Level

Compare Levels

Existing model is Validated Take additional

measurements, adjust model, and/or document

why not validated

NO YES

Is difference within(+/-) 3 dB(A)?

Use to predict existing noise (with TPP traffic) and update with future design and traffic

to predict future noise

ENV Traffic Noise Toolkit

www.txdot.gov/inside-txdot/division/environmental/compliance-toolkits/traffic-noise.html

Memo summarizing changes & effective date

2019 Noise Policy

Coming Soon!Noise Policy Implementation Guidance

FHWA-ApprovedCost Proposal Memo

Alternate Barrier CostAssessment Worksheet

Training

ENV125 – Traffic Noise BasicsProvides a general overview of the Traffic Noise process, including the new noise policy and concentrating on interpretation of results and documentation requirements. (Pre-requisite for ENV115)

ENV115 – Traffic Noise Analysis Teaches how to prepare a traffic noise analysis using the TNM 2.5 software and how to document the analysis. Students should have some familiarity with GIS and CAD applications.

Next Class: November 13-14, 2019 (Austin)

Next Class: November 12, 2019 (Austin)

Conclusion

Summary of Big Changes for 2019 Noise Policy:– 1 Validation Requirements– 2 New Feasible Criteria for Abatement– 3 New Cost Reasonable Criteria for Abatement– 4 Noise Workshop Voting Changes

2019 Policy Goes into Effect December 31, 2019!!!!

Contact ENV Noise SMEs

Ray Umscheid512-416-3025Ray.Umscheid@txdot.gov

Meredith Worthen512-416-2612Meredith.Worthen@txdot.gov

Questions?

2019 Traffic Noise Policy - Texas A&M University · 2019. 11. 4. · ENV125 – Traffic Noise...

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