To help ensure that comparative analyses of project alternatives include consideration for minimizing or avoiding traffic noise impacts, comprehensive planning and coordination should be accomplished as early as possible in the project development process. This could reduce or eliminate the need for costly abatement later in the design process. This section focuses primarily on environmental noise procedures for highways. The level of noise (defined as unwanted sound) near state highways depends on six things:

Ø Traffic volume

Ø Speed of the traffic

Ø Percentage of trucks in the flow of traffic

Ø Distance to the highway

Ø Intervening topography and structures

Ø Atmospheric conditions

The Federal Highway Administration (FHWA) has established Noise Abatement Criteria guidelines (absolute noise impact) for several categories of land use activities; which include the following Leq noise levels:

Category A Leq = 57 dBA Lands on which “serenity and quiet are of extraordinary

significance and serve an important public need……”.

Category B Leq = 67 dBA Picnic areas, recreation areas, parks, residences, motels,

schools, churches, libraries, and hospitals.

Category C Leq = 72 dBA Developed lands, properties or activities not included in

Category A or B (i.e., most commercial and industrial

Activities).

Category D Leq = -- Undeveloped lands.

Category E Leq = 52 dBA Interior of residences, libraries, etc.

In determining and abating traffic noise impacts, primary consideration is to be given to exterior areas. Abatement will usually be necessary only where frequent human use occurs and a lowered noise level would be of benefit.

Heavier traffic volumes, higher speeds, and a greater percentage of trucks generally increase traffic noise. ITD has several strategies for controlling highway noise:

· Preserve existing buffer zones. Work with local jurisdictions to retain lands adjacent to highways in open space uses, promote the use of berms, and preserve beneficial topographic features along with the use of trees, shrubs, and other vegetation to soften the landscape.

· Support local jurisdictions in establishing principal routes for buses and trucks.

· Review local land use plans and advise local agencies to help achieve compatible development along highways.

· Identify potential noise impacts and mitigation measures early in the planning and design stages of highway improvements.

· When applicable, purchase R/W for lane additions from the side least affected by noise and other environmental impacts rather than purchasing equal amounts of R/W from each side. This strategy not only reduces environmental impacts, it reduces the number of R/W negotiations with adjacent property owners and can improve noise levels for residences on the opposite side of the road.

1310.01 Summary of Requirements. A traffic noise analysis is required by law for Type I federally funded projects. Type I projects:

· Involve construction of a highway on new location,

· Substantially change the horizontal or vertical alignment of an existing highway,

· Increase the number of through traffic lanes on an existing highway.

FHWA policy memorandums have clarified that “increasing the number of through traffic lanes on an existing highway” includes:

· The addition of ramps or ramp lanes at interchange locations,

· The addition of an auxiliary lane between interchanges if the lane is at least 1.5 miles long or if the lane is made continuous through a series of successive interchanges, or

· The addition of a full lane to a highway.

In rare cases, a traffic noise analysis is also required for projects that are not Type I. This occurs when the project itself creates a noise impact, for instance when a sideslope or berm is flattened for design purposes and adjacent noise sensitive receptors are affected.

Section 1300.05 provides technical guidance for implementing the noise analysis process.

1310.02 Abbreviations and Acronyms. Abbreviations and acronyms used in this section are listed below. Others are found in the general list in the appendix.

· dBA ---- A-weighted decibels

· DHV--- Design Hour Volume (30^th highest traffic volume in a given year)

· FHWA – Federal Highway Administration

· ITD ----- Idaho Transportation Department

· Leq ----- Equivalent sound level

· LHTAC Local Highway Technical Assistance Council

· LOS --- Level-of-Service

· NAC ---- Noise Abatement Criteria

· TNM---- Traffic Noise Model

130.03 Glossary.

Abatement – An action taken to reduce the impact of highway traffic noise.

Abatement Measures – Measures that must be considered in a traffic noise impact report when a highway project will result in a noise impact. This includes the following six measures:

Traffic management,
Alteration of horizontal and vertical alignments,
Acquisition of real property to serve as a buffer zone,
Construction of noise barriers,
Acquisition of property rights for barrier construction purposes, and
Insulation of public use, nonprofit institutional structures.

‘Absolute’ Noise Impact – One of two criteria used to determine when a noise impact occurs. Under this criterion, a noise impact occurs when the predicted noise level approaches or exceeds the FHWA Noise Abatement Criteria (NAC).

Alpha Factor – Modeling term used to differentiate terrain reflective characteristics. For example, decibel levels decrease 3 dB per doubling of distance over asphalt or concrete (‘hard’ alpha), and 4.5 dB per doubling of distance over plowed ground or ground thickly covered with vegetation (‘soft’ alpha).

Approach – Means one (1) dBA below the FHWA “Absolute” noise impact criterion.

Barrier Cost Planning Estimate – Determined by multiplying the length times the height of a proposed noise wall by $20 sq. ft. regarding walls over a quarter mile long, or $25 sq. ft. for proposed walls less than a quarter mile long. (These costs are applicable until August 2005; updated cost information will be evaluated at that time, as described in Section 1300.05(8).)

Benefited Receptor – A receptor that is projected to receive a noise reduction of 5 decibels (dBA), or more, as a result of proposed noise mitigation measures. All benefited receptors should be included when counting receptors, regardless of whether or not they were identified as impacted. Each unit in a multifamily building should be counted as a receptor in determining impacts; each benefited unit should be counted as a receptor in determining benefits.

Cost/Benefited Receptor – The dollar amount used in determining cost reasonableness of noise abatement.

Cost Effectiveness – Determined by multiplying the total number of benefited receptors by $20,000 and subtracting the estimated cost of constructing an effective noise wall. A positive remainder means the barrier is cost effective. (The $20,000 per receptor amount has been established for use until August 2005; it will be re-evaluated and possibly updated at that time, as described in Section 1300.05(8).)

dBA – The most generally used measure of the magnitude of traffic noise. The decibel (dB) or one-tenth of a Bel is a measure on a logarithmic scale which indicates the ratio between two sound powers. A ratio of 2 in power corresponds to a difference of 3 dB between the two sounds. The ‘A’-weighting tends to de-emphasize lower-frequency sounds (e.g., below 1,000 Hertz) and higher frequency sounds (above 4 Kilohertz) in an effort to mimic human hearing.

Date of Public Knowledge – The date of approval of the environmental determination (CE, FONSI or ROD) for a highway project. After this date, federal and state governments are no longer responsible for providing noise abatement for new development adjacent to the highway project.

Design Hourly Volume (DHV) – The traffic volume determined by ITD to normally represent the worst hourly traffic noise impacts on a regular basis in a given year. The DHV is used for design purposes as well as to model ‘current’ and ‘design year’ noise levels. These traffic volume estimates must be obtained from ITD District via the ITD HQ Planning Division.

Design Year – The future year used to estimate the probable traffic volume for which a highway is designed, usually 10 to 20 years from the beginning of construction.

Effective Noise Wall – A noise wall that provides a minimum insertion loss of 10 dBA at 10 feet and 5 dBA at 100 feet behind the wall, as well as a minimum 5 dBA insertion loss within 10 feet of the receptor(s) of concern.

Insertion Loss – The net change in noise level at a receiver location due to the installation of a barrier. For purposes of this document, the term may be used interchangeably with “attenuation” or “noise reduction”.

Leq – The equivalent steady-state sound level, expressed in decibels, which in a stated period of time (e.g., design hour) contains the same acoustic energy as the time-varying sound level during the same period of time.

Level of Service – A qualitative measure describing operational conditions within a traffic stream; generally described in terms of such factors as highway type, speed and travel time, freedom to maneuver, traffic interruptions, comfort and convenience, safety, and traffic volume.

Noise Abatement Criteria (NAC) – Noise levels for various activities or land uses established by FHWA, that are used to determine when an ‘Absolute’ noise impact occurs. NAC are not to be used as a design goal for a noise abatement measure.

Planned, Designed and Programmed – Means that the building permit(s) for development of undeveloped land has been issued by the local jurisdiction at the time of the noise analysis, or that the implementation of an approved final plat is in progress (i.e., streets and utilities are in place or under construction).

Receiver – Alternative to the term ‘receptor’.

Receptor – Residences, businesses and outdoor areas where highway traffic noise may affect frequent human activities. The closest corner of a residence (or business receptor) to highway centerline is to be used as the receptor location in modeling traffic noise impacts and attenuation projections. (Each direction of travel should be modeled as a separate roadway on divided roads). Sound level meter measurements should not be located closer than 10 feet from a building. Therefore, when taking field measurements at receptor sites involving buildings, the meter should be located at least 10 feet from the closest corner and at an equal distance to the highway. In the case of outdoor areas, the closest active recreational use facility (e.g., patio, campground site, swimming pool, tennis court, picnic shelter) to the highway is to be used as the receptor location in modeling traffic noise impacts and attenuation projections.

Relative Noise Impact – One of two criteria used to determine when a noise impact occurs. Under this criterion, a noise impact occurs when the project design year noise level exceeds the existing traffic noise level by 15 dBA or more; even if it does not approach or exceed the ‘Absolute’ noise abatement criteria.

Shielding factor – Any constructed or natural barrier located between the roadway and receptor which provides a reduction in roadway traffic noise at the receptor site.

Stamina 2.0/Optima – FHWA traffic noise model which is being phased out by the new TNM modeling software. When approved by ITD and FHWA, Stamina may still be used for a limited time only; final phase-out is expected approximately December 2004. The use of the same model is encouraged throughout the life of a project (i.e., planning, environmental analysis, preliminary and final design).

Substantial Increase – Alternative to the term ‘relative noise impact’.

Substantial Reduction – Noise level reduction of at least 5 dBA at impacted receptors.

Ten-point Transect – A line perpendicular to the highway upon which noise receptor locations are modeled at 50ft, 75ft, 100ft, 125ft, 150ft, 200ft, 250ft, 300ft, 400ft, and 800ft from centerline of an undivided highway or directional centerline in the case of a divided highway. This transect data will be provided to local officials in an effort to prevent future traffic noise impacts on currently undeveloped lands in conformance with 23 CFR 772.15. This transect data is also useful in determining the distance to model receptor locations on developed sites regarding noise impact analysis.

TNM – Transportation Noise Model, Federal Highway Administration’s computer program for highway traffic noise prediction and analysis. TNM replaces FHWA’s prior prediction model and the Stamina/Optima computer programs.

Trucks – Heavy trucks have 3-axles or more, medium trucks have 2-axles and 6-wheels.

Type I Project – A proposed highway construction at a new location or the physical alteration of an existing highway that significantly changes either the horizontal or vertical alignment or increases the number of traffic through lanes.

Type II or Retrofit Project – A stand alone federal-aid project (retrofit project) for noise abatement on an existing highway.

Section 1320.00 – Applicable Statutes and Regulations

1320.01 National Environmental Policy Act. The National Environmental Policy Act (NEPA), 42 USC 4231, requires that all actions sponsored, funded, permitted, or approved by federal agencies undergo planning to ensure that environmental considerations such as noise impacts are given due weight in project decision-making. Federal implementing regulations are at 23 CFR 771 (FHWA) and 40 CFR 1500-1508 (CEQ). For details see Section 310 through Section 312.

1320.02 Federal-Aid Highway Act of 1970 and Implementing Regulations. The Federal-Aid Highway Act of 1970 authorized the development of highway traffic noise standards. 23 USC 109 (i) directs the Secretary of Transportation to develop and implement traffic noise standards for highway projects. Noise impact criteria and abatement procedures implemented by FHWA are in 23 CFR 772 (Procedures for Abatement of Highway Traffic Noise and Construction Noise). This regulation requires preparing a noise study to determine what noise impacts, if any, will result from the proposed highway improvement and what measures will be taken to lessen these impacts. If noise impacts are expected, noise-reduction measures that are determined by ITD and FHWA to be reasonable and feasible must be incorporated into the highway improvement. Laws and regulations can be accessed at the web site below:

http://www.access.gpo.gov/nara/cfr/

Section 1330.00 – Policy Guidance (Reserved)

Section 1340.00 - MOU’s/MOA’s (Reserved)

Section 1350.00 – Technical Guidance

Guidance for conducting traffic noise studies and preparing documentation is provided in the documents described in this section. The purpose of this guidance is to determine if the proposed project will create noise impacts, and if so, the likelihood of providing abatement measures. In addition, to lessen the likelihood of future noise impacts, local officials are to be provided appropriate information for their land-use planning and implementation efforts.

1350.01 Information for Local Officials .

· District/LHTAC environmental staff will provide the local jurisdiction with an estimation of future noise levels (for various distances from the highway improvement) for both developed and undeveloped lands or properties in the immediate vicinity of the project. (See Exhibit 1300-1)

· District/LHTAC staff will also provide information that may be useful to local communities to protect future land development from becoming incompatible with anticipated highway noise levels. Local officials responsible for issuing building permits or approving plat requests for future development adjacent to the project should be encouraged to include a statement on the permits/plats indicating that the developer will be responsible for either avoiding traffic noise impacts or providing any associated abatement.

· District/LHTAC staff will provide local officials with information regarding eligibility for Federal-aid participation for Type II projects as described in 23 CFR 772.13(b). ITD does not program Type II projects. (Refer to Section 1300.05(7) for further information on Type II projects).

· In addition, local officials are to be reminded that after the date of public knowledge, ITD & FHWA are not responsible for noise abatement in the project area.

· Notification shall be sent to local officials by the District (or LHTAC) no later than 10 days after approval of the CE, FONSI, or ROD by FHWA.

Exhibit 1300-1 and Exhibit 1300-2 display the recommended format and sample cover letter for the local officials information. This information will be sent by the District or LHTAC to the Mayor/City Manager or Chairman of the Board of County Commissioners with copies, as applicable, to:

· Chairman of the Planning Commission

· Director of the Planning and Zoning Dept.

· City/County Engineer

· Chief Building Inspector

· HQ Environmental Manager

1350.02 Traffic Noise Screen.

· A noise screen will be conducted by District environmental staff or LHTAC on all Type I projects, except projects involving new alignments. Projects involving new alignments will always require a traffic noise impact analysis.

· District/LHTAC environmental staff will use the FHWA TNMLOOK model to determine the predicted design year traffic noise level for applicable receptor sites adjacent to the highway project (i.e., the closest FHWA category B receptor to the roadway, as well as any category C receptor located closer than the closest Category B receptor; Category A receptors should be referred to ITD HQ for resolution). Model input should be based on design hour volumes (DHV) at posted speeds. TNMLOOK is based on a straight roadway and flat terrain; as conditions deviate from this, reliability decreases.

If-the closest Category B receptor to the roadway (including undeveloped lands where development is planned, designed, and programmed) does not exceed 60 dBA, no further noise analysis is necessary. The same principle would apply to Category C receptors, i.e., if the closest does not exceed 65 dBA, no further noise analysis is necessary. If the closest category B receptor to the roadway does not exceed 60 dBA and no traffic noise impacts are anticipated on undeveloped lands where development is planned, designed and programmed, then no further noise analysis is necessary, unless a category C receptor is predicted to approach or exceed 72 dBA in the design year. The noise model printouts showing these results should be attached to the Environmental Evaluation submittal package or EA and appropriately referenced in the document. For example the Environmental Evaluation 654 Form would have ‘No’ checked alongside ‘#1. Noise’ and a short statement referencing the noise printout in the Environmental Evaluation Summary Sheet or the EA Impact Section, such as: “As indicated on the attached Noise Screen Printouts, the predicted noise level at the closest residence to the roadway is __ dBA; since this level is noticeably below the FHWA Noise Abatement Criteria, the project will not result in a traffic noise impact”.

If predicted design year noise levels exceed 60 dBA, then continue with Section (3), below. Generally, Section (3) will require the services of a traffic noise consultant.

1350.03 Traffic Noise Impact Analysis. The outline below serves as a general guide for preparing a traffic noise analysis report. For those existing alignment Type I projects which have been screened out by the District, LHTAC, or HQ Environmental staff using the screening procedure in Section 1300.05(2), the resulting screening documentation is sufficient and a complete traffic noise analysis report is not necessary. The latest version of TNM is the preferred analysis method. For cases in which a traffic noise analysis is necessary based on the results of screening, the report will include:

· A brief description of the Project and Affected Environment

- A brief description of the project.

- Identifying the local jurisdiction and their efforts/ordinances to promote compatibility between land development and highways regarding noise abatement.,

- Identification of noise sensitive areas and receptors with potential noise impacts.

- A description of the existing land use and if the land use is changing, and

- A Figure depicting the zoning in the project area.

· An Impact Analysis

- A table displaying existing and design year noise levels, which includes distance to centerline for receptor locations (build & no-build). Each direction of travel should be modeled as a separate roadway on divided roads. Document all noise levels on the table in whole numbers. A sample table is presented in Exhibit 1300-3. Formatting the table in this manner is recommended to facilitate application of the abatement checklists.

a. Because design year noise levels can only be determined by computer modeling, existing noise levels should also be determined by computer modeling to allow a direct comparison of noise levels obtained by the same methodology.

b. Field measurements are required to calibrate and validate the model. Representative sites, including the closest residence to the roadway, are to be selected for measurement. Each site selected shall include a minimum of three 10-minute traffic counts (cars, medium trucks & heavy trucks) concurrent with a sound level meter reading. 10 minute counts are easily converted to 60 minute counts for insertion into the FHWA model by simply multiplying the respective vehicle count by 6 (e.g., 123 cars becomes 738 cars, 7 medium trucks becomes 42 medium trucks, etc.). More than 3 counts or sampling periods greater than 10 minutes may be required to ensure statistically reliable data, as determined by the noise analyst’s judgment and based on the traffic volumes of the roadway under study (lower volume roadways require longer sampling periods, and time periods of an hour or even 24 hours could be required, depending on the traffic volume). Actual meter readings are to be compared with results from the FHWA model. Adjustments to variables within the model may be necessary to calibrate the model. To be validated, the model must be within 3 dBA of the applicable meter reading; unless it can be documented that noise from other sources has a noticeable effect on the field measurements.

c. In cases where highway traffic is not the dominant source of noise, the dominant source must be identified and noise levels produced by that source(s) displayed on the table and factored into the analysis.

d. Truck percentage ratio between medium and heavy trucks should be determined from observed traffic counts, if not otherwise available.

- Figure(s) identifying receptor locations & type, right-of-way lines, centerlines, property access, crossroads, and any shielding/barrier information which can markedly influence impact results or abatement considerations (e.g., receptors located on complex hilly terrain may require topographic contour lines and spot elevations, whereas this data can be ignored given relatively level terrain conditions); and

- Narrative identifying NAC criteria, receptors impacted & severity of impact [e.g., are impacts less than, equal to, or greater than the no-build scenario; are increases unnoticeable (< 3 dBA), slightly noticeable (3 to 5 dBA), noticeable (5 to 15 dBA), or substantial (>15 dBA).

-Analysis , modeling, and field measurements may result in decimal dBA values, however, these decimal values should be rounded (not truncated) to the nearest whole number for presentation in the tables and text of the analysis report.

· Abatement Considerations

- Non-barrier & Barrier Checklists (Exhibits 1300-4 & 1300-5, respectively) serve as a general guide and should be used to assess noise abatement measures. Both of these checklists first consider feasibility of noise abatement. When measures are deemed feasible, the checklists proceed to evaluations of reasonability of abatement. After completion of these checklists, the District will complete the Noise Abatement Decision document presented in Exhibit 1300-6 for each receptor or group of receptors.

a. Truck Restrictions may be evaluated as a traffic management measure to mitigate traffic noise in cases where such restrictions do not conflict with the intended use of the roadway or create unreasonable delay or hardship on the motoring public.

b. Speed restrictions may be evaluated as a traffic management measure to mitigate traffic noise where these restrictions do not conflict with the roadways designated use, they do not create unreasonable delay or hardship on the motoring public, and they do not create a safety or enforcement problem.

c. A depressed roadway can effectively mitigate much of the traffic noise to adjacent receptors. If a project needs additional fill material, a lower roadway grade may be a cost effective method to provide fill material while reducing traffic noise, or to provide berm material for noise barrier purposes.

d. The views of impacted residents are to be a major consideration in reaching a decision on noise barrier implementation (i.e., Barriers will not be built if most affected residents do not desire them).

- The text should identify “no solution” receptors for which abatement is not feasible or not reasonable & why, and

- Text should include costs, noting receptors for which measures are feasible & reasonable and ‘likely’ to be incorporated into the project.

· Construction Impacts

- Construction noise should be addressed in a general manner with emphasis on the temporary nature of any adverse effects.

- Common, easy to implement measures to minimize construction noise should be included in the plans and specifications for a highway project (e.g., work-hour limits, equipment muffler requirements, etc.). Exhibit 1300-7 provides an example of how to address construction noise impacts for routine projects.

- The calculation of noise levels for highway construction equipment is normally not required in a traffic noise analyses.

· Analysis Methodology

- Traffic data used (volumes, mix, posted speed) and source,

- Explain any alpha factor or other adjustments to the model (shielding, barrier cost assumptions, etc.),

- Any other applicable assumptions, along with a statement explaining that the analysis conforms with 23 CFR 772.

As the scope of the project warrants, appendices to the Traffic Noise Impact Report may include supporting documents, such as:

· Output tables (current existing, design year existing, design year proposed)

· Feasible & Reasonable worksheets

· Traffic data sheets

· Typical sections

· Photographs

· Bibliography/References

· Excerpts from local ordinances or land-use plans

· Construction noise/mitigation for non-routine circumstances (i.e., projects with unusually severe highway construction noise impacts).

1350.04 Data Requirements. Before requesting a traffic noise impact report, the ITD/LHTAC project manager may need to compile relevant data that will be needed by the analyst. Such data can include:

· Plan sheets or Micro Station files for the project showing

1. Receptor locations (labeled as to type),

2. Current and proposed route centerlines & right-of way lines,

3. Current zoning classifications,

4. Topography & spot elevations,

5. Scale & north arrow,

· Provide land use information and zoning maps and indicate whether or not the local jurisdiction anticipates any changes in the project area regarding zoning and land use, and note if they have any noise controls in effect which preclude landowners/developers from creating new noise sensitive land uses adjacent to the route.

· Provide typical sections of existing and proposed route.

· Provide current and design year traffic data , including traffic volumes (DHV) and truck % on project area roadways (this data is required for any crossroads that may impact receptor locations or interfere with abatement considerations and for each project section for which there is a change in posted speed or 25% change in traffic volume).

· Provide current and projected posted speeds on all roadway sections in the project area

· Indicate any other important sources of noise in proximity to the project area (e.g., railroad, airport, industrial site, crusher operation, etc.) and give the location and approximate distance to the route in question.

· Note any special route characteristics (e.g., truck route, signing to prohibit trucks at certain times, one-way traffic, business route, etc.)

· Provide any other information deemed important to the noise analysis; this may include survey data, petitions, complaints, route history, when adjacent subdivisions were given final plat approval, when building permits were issued, any direct/indirect effects on historical sites, jurisdictional desires, etc.)

1350.05 Consultant Scopes of Work. Exhibit 1300-8 is a sample scope of work that can be used as a guide in contracting with consultants for traffic noise impact studies.

1350.06 ITD Traffic Noise Analysis and Abatement Policy and Procedures.

ITD will provide constructive recommendations to local jurisdictions to avoid future traffic noise impacts when they are considering development permits adjacent to highways.
ITD will consider abatement measures to alleviate traffic noise impacts adjacent to Type I projects, and implement any measures considered feasible and reasonable.
ITD will consider residences and other sensitive land uses to be reasonable candidates for the construction of noise walls. To provide effective sound barrier protection above the first floor of a multi-story sensitive receptor is normally not considered reasonable. (Walls constructed tall enough to break the line of sight for upper story units are seldom acceptable to ground floor residents and the additional reinforcement and foundation improvements for wind loading result in significantly greater construction costs.) Exceptions involve multistory apartments constructed below highway centerline because of terrain conditions.
ITD considers sound walls for parking lots, highway businesses, and other commercial or industrial enterprises not to be a reasonable expenditure of public funds unless special conditions exist. These uses are commonly located adjacent to highways for business exposure, and are dependant on transportation access.
ITD advocates that local jurisdictions use their power to regulate land development in such a way that noise-sensitive land uses are either not allowed adjacent to a highway, or that the developments are planned, designed, and constructed in such a way that traffic noise impacts are minimized.

Noise barriers will not normally be expected for dwellings with access directly onto the highway (i.e., for reasons of poor barrier performance and poor sight distance). Reconfiguring neighborhoods, including streets, houses and access to private property, to arrange noise walls would not normally be considered feasible; except in cases where moving a driveway access can benefit project design/purpose or, with the consent of the property owner, can be arranged in such a manner that an effective sound wall can be constructed without exceeding cost reasonableness criteria.
ITD considers noise barriers to be the primary noise abatement measure. Barrier costs include the cost of construction.
A noise abatement measure will not be implemented where it will create a hazard, violate design standards or create an adverse impact on a cultural resource on-or-eligible for the National Register of historic places. (Although the following conditions can often be resolved thru use of good design principles; consider recovery zone, snow accumulation and removal, sight distance, barrier rail, drainage, utility easements, etc.)
Noise insulation of public use or non-profit institutional structures may be considered for those cases dealing with interior traffic noise impacts created by the ITD project.
Noise abatement will not be implemented if the majority (50% +1) of the impacted people are in opposition or indifferent to noise mitigation. Opposition to barrier construction shall be documented in writing, such as formal surveys or petitions.
Noise barriers should not be proposed in locations that cause residential or commercial displacements to result from barrier installation.
Trees and shrubs provide psychological benefits and may be provided for privacy or aesthetic purposes, but should not normally be considered as a noise abatement measure.
Reasonable effort should be made to preserve natural vegetation whether or not noise abatement is proposed. Dense stands of vegetation that already exist along a highway, for example, may provide a perceptible amount of noise reduction for some receptors and should be preserved when possible (e.g., dense vegetation 15 feet high by 100 feet deep provides a 5 dBA decrease in noise levels).

1350.07 Type II Noise Evaluation Procedures for Existing Highways.. ITD does not program Type II projects. Local jurisdictions, however, which have adopted traffic noise control ordinances regarding new development, may desire to program such projects. Any local jurisdiction desiring to expend Federal-aid highway funds for Type II abatement should develop a jurisdiction-wide Type II program (i.e., survey, analyze, prioritize, and implement). A Type II program can insure uniformity and consistency in the decision-making process, thereby avoiding ‘arbitrary and capricious’ actions vulnerable to complaints of discrimination. If programmed, any Type II project proposed for Federal-aid highway participation would be covered by the provisions of State and Federal noise policy. Type II abatement may not be approved for homes that were constructed prior to a local community’s adoption of an active noise-compatible land use control program.

23 CFR 772.13(b) states that noise abatement measures will only be approved for Type II projects that were approved before 28 November 1995, or are proposed along lands where land development or substantial construction predated the existence of the highway. The granting of a building permit, filing of a plat plan, or a similar action must have occurred prior to right-of-way acquisition or construction approval for the original highway. Noise abatement measures will not be approved at locations where such measures were previously determined not to be reasonable and feasible for a Type I project.

To avoid any potential Title VI and/or Environmental Justice complaints, local jurisdictions may consider constructing retrofit noise abatement (Type II projects) using only local or private funds.

1350.08 Noise Barrier Information Database and Evaluation of Cost Effectiveness. ITD will maintain a database of noise barrier information, consisting of the following information for all completed projects which required noise barriers:

Project Name and number
Route and County location
Barrier type and material
Construction date
Barrier length (linear feet)
Barrier height
Total cost of barrier
Unit cost per square foot of noise wall

Cost information derived from this database will be used to establish barrier cost planning estimates and cost effectiveness. Barrier cost planning estimate will be based on the average unit price of noise walls on representative recent projects. Initial values of the barrier cost planning estimate and the limit of cost-effectiveness have been established as identified in Section 1300.01(3). An initial review of these items will be submitted by ITD to FHWA in July 2005. This information and possible need for revisions will be evaluated in August 2005 and on a biennial basis thereafter. These cost planning estimate and cost-effectiveness review submittals will include complete information from the noise barrier database, along with ITD’s computations and recommendations for adjustment of these values.

1350.09 FHWA Guidance and Reference Information.

FHWA Technical Advisory T6640.8A (October 1987) gives guidelines for preparing environmental documents. For noise, summary of the noise analysis should include the following:

Brief description of noise-sensitive areas, including developed and undeveloped areas for land uses such as residences, business, schools, and parks.

Extent of the impact (in decibels) at each sensitive site.

Noise abatement measures considered for each impacted area, and costs for those likely to be incorporated into the proposed project.

Noise impacts for which no prudent solution is reasonably available and the reasons why. http://www.fhwa.dot.gov/legsregs/directives/techadvs/T664008a.htm

FHWA Highway Traffic Noise Analysis and Abatement, Policy and Guidance

This document (June 1995) is available at the Highway Traffic Noise Rules, Policy, and Technical Advisories web site:

http://www.fhwa.dot.gov/environment/noise/mem_nois.htm

FHWA Guidance on Construction Noise

FHWA guidance on highway construction noise can be found in FHWA Technical Advisory

T6160.2, Analysis of Highway Construction Noise. March 13, 1984, available online at:

http://www.fhwa.dot.gov/legsregs/directives/techadvs/t616002.htm

An earlier reference is FHWA’s Special Report, Highway Construction Noise: Measurement, Prediction and Mitigation (May 2, 1977).

Other Technical Resources

FHWA’s environment home page contains links to numerous references on highway traffic noise analysis and abatement resources:

http://www.fhwa.dot.gov/environment

Section 1360.00 – Permits and Approvals

Each local jurisdiction will need to be contacted to determine the local regulations and if permits or other actions are required.

Section 1300.07 – Non-Road project Requirements (Reserved)

Section 1380.00 – Exhibits

EXHIBIT 1300-1 INFORMATION for LOCAL OFFICIALS (Sample)

In Accordance with 23 CFR 772.15

The Federal Highway Administration (FHWA), has established absolute noise level guidelines for several categories of land use activities; which include the following L_eq noise levels:

Category A Leq = 57 dBA Lands on which "serenity and quiet are of extraordinary significance and serve an important public need.....".

Category B Leq = 67 dBA Picnic areas, recreation areas, parks, residences, motels, schools, churches, libraries, and hospitals.

Category C Leq = 72 dBA Properties/activities which are not included in category A or B (e.g., most commercial and industrial activities).

Table 1

Projected Design Year (2025) DHV L_eq Noise Levels (dBA)

@ Selected Distances & Posted Speeds

WAYNE, ID

4th St. 1st Blvd I-94

Transect: 30mph 35mph 65mph

1. 50' of CL [Centerline] 65 66 NA

2. 75' of CL 63 65 NA

3. 100' of CL 60 63 76

4. 125' of CL 59 62 74

5. 150' of CL 58 61 73

6. 200' of CL 56 59 71

7. 250' of CL 55 58 70

8. 300' of CL 54 57 68

9. 400' of CL 52 54 67

10. 800' of CL 47 50 62

Noise abatement measures recommended for consideration by the local jurisdiction in the project area:

(1) Requiring developers to implement suitable noise abatement measures in those cases where adequate setbacks or buffer zones are not maintained (e.g., berms, sound walls, insulation, double/triple pane windows, etc.);

(2) Requiring acceptable setbacks or buffer zones for new residential units or developments (i.e.; Table 1 indicates 75' of centerline would be an appropriate distance to construct residences adjacent to 1st Blvd in order not to approach or exceed FHWA noise abatement guidelines);

(3) Maintaining appropriate zoning for non-sensitive land uses adjacent to the route;

(4) Lowering or maintaining (not raising) the current posted speed limits.

(5) Include a statement on any development/building permit indicating that the developer will be responsible for either avoiding traffic noise impacts or providing any associated abatement.

Type II Project Eligibility [23 CFR 772.13(b)]

For Type II projects, noise abatement measures will only be approved for projects that were approved before November 28, 1995, or are proposed along lands where land development or substantial construction predated the existence of any highway. The granting of a building permit, filing of a plat plan, or a similar action must have occurred prior to right-of-way acquisition or construction approval for the original highway. Noise abatement measures will not be approved at locations where such measures were previously determined not to be reasonable and feasible for a Type I project.

Date of Public Knowledge

The approval date of the environmental determination (i.e., CE, FONSI, ROD); after this date FHWA & ITD are no longer responsible for providing noise abatement for new development adjacent to the highway project.

The date of public knowledge for this project is: ____________________.

EXHIBIT 1300-2 Sample Cover Letter re: Information to Local Officials.

[The following is a sample letter of notification to local officials concerning possible future development noise impacts from an ITD project. Notification shall be sent to local officials by the District/LHTAC no later than 10 days after approval date of the CE, FONSI, or ROD by FHWA.]

4 July 2003

Webster County Commissioners, Chairman

Box 1776

Mason, Idaho 83000

RE: Project STP-7777 (333)

US66, Mason to Jct. SH99

Key No. 4432

Dear Mr. Smith,

The Idaho Transportation Department is proposing to construct an additional lane on each side of US66 from Mason Street to the junction of SH99 in Webster County. This road widening project will result in traffic noise projections as depicted on the attached table of transects.

The attached table of transects were completed during the course of the traffic noise analysis for this project. This information depicts the noise level anticipated to be produced by the projected design year traffic volume (year 2025). There are a number of vacant properties along US66 that may be developed over the next several years and construction close to the travel lanes may result in a volume of noise sufficient to exceed Federal traffic noise abatement criteria. In planning for future development along the US66 project limits please note that traffic noise may become a factor and that any building or development plans should take this issue into consideration.

This notification of future noise impacts and the possibility of Federal funding for noise abatement are issued in accordance with 23 Code of Federal Regulations 772.15.

Sincerely,

District or LHTAC Official

Attachment

Cc: Planning and Zoning Commission

City Planning Department

County Planning Department

Local Metropolitan Planning Organization

City Mayor

ITD Environmental Manager

The notification letter based on the foregoing example is addressed to the County Commissioners and copied to several entities. Each project will be different and the appropriate agencies and entities should be selected for notification according to which agency has jurisdiction in the project area. The letter must include the predicted (design year) noise levels at prescribed distances from the centerline of the street or road. If the District/LHTAC wishes to do so, the letter may state that the district, LHTAC or HQ staff is available for additional information on noise abatement if desired by the agency contacted.

EXHIBIT 1300-3 SAMPLE TABLE DISPLAYING RECEPTOR INFORMATION.

Table 1

Current & Projected L_eq Noise Levels (dBA)

US-95

Receptor Distance from Centerline NOISE LEVEL

(See Fig. 1) Existing Proposed 1998 2018

W/O With Project Project

65 mph Section:

# 1-Residence 98' Displace 68 70 Displace

# 2-Salvage 39' 69’ 72 74 71

# 3-Mobile Home 250' 207’ 64 66 66

# 4-Residence 122' 79’ 67 69 71

# 5-Radio Station 129' 86’ 67 69 70

45 mph Section:

(No Receptors)

35 mph Section:

# 6-Church 163' NC 61 63 63

# 7-Car Dealer 119' NC 62 64 64

# 8-Farm Equip. 161' 158' 60 62 62

# 9-Car Rental 132' 135' 61 63 63

#10-Restaurant 144' 141' 61 63 63

#11-Tavern 89' 79' 63 65 65

#12-MH Court 119' 109' 61 63 64

Project Name:__________________________________ Project#_______________ Key#_______

EXHIBIT 1300-4 Idaho Transportation Department (ITD).

NON-BARRIER NOISE ABATEMENT CHECKLIST

FEASIBILITY: YES NO

1. Can traffic management measures be implemented which conform to

the purpose of the project and achieve at least a 5 dBA reduction in

sound levels at the impacted receptor(s)? ___ ___

2. Can alignment alteration be implemented which conforms to design

standards and achieves a 5 dBA reduction in sound levels at the

impacted receptor(s)? ___ ___

3. Can a buffer zone be provided which achieves a 5 dBA reduction in

sound levels at the impacted receptor(s) and results in no displacements? ___ ___

4. Is there an impacted public use or non-profit institutional structure

in the project area and can insulation be provided which achieves a

5 dBA reduction in sound levels inside the structure? ___ ___

If no to all of the above, these measures are not feasible. END

If yes to any of the above, the measure is feasible, therefore consider the following:

REASONABILITY: YES NO

1. Does cost of implementation meet the cost per benefited residence

criterion? ___ ___

2. Does this measure conform to local plans and land use regulations?___ ___

3. Is the measure consistent with state and federal environmental laws,

regulations and best management practices? ___ ___

4. Additional considerations:

DESIRABILITY: YES NO

Does the local jurisdiction endorse the measure(s)? ___ ___

Project Name:___________________________ Project#_____________ Key#_______

EXHIBIT 1300-5

ITD NOISE BARRIER ABATEMENT CHECKLIST

BARRIER FEASIBILITY: YES NO

1. Can the barrier achieve at least a 5dBA sound level reduction at the

impacted receptor without limiting property or neighborhood access? ___ ___

2. Does the barrier conform to project standards regarding traffic safety,

maintenance and drainage concerns, considering that these issues

can often be resolved through use of good design practices? ___ ___

3. Can an effective barrier be constructed considering the existing site

characteristics and topography, and without reconfiguring the site

or neighborhood (not including minor access modifications)? ___ ___

4. Is traffic noise the dominant noise source in the project area, and will

the barrier be effective in spite of any other source not associated with

the project? ___ ___

If no to any of the above, the barrier is not feasible. END

If yes to all of the above the barrier is feasible, therefore consider the following:

BARRIER REASONABILITY: YES NO

High Low Low High

1. Development pre-dated highway const. ____ ____ ____ ____

>80% 50-80% 30-49% <30%

2. Development in place before 1976 ____ ____ ____ ____

>80% 50-80% 30-49% <30%

3. Design year ‘build’ dBA level (w/o barrier) ____ ____ ____ ____

>72dBA 66-72 60-65 <60dBA

4. Design year ‘build’ dBA level > current year no-build ____ ____ ____ ____

>10dBA 5-10 3-4 <3dBA

5. Design year ‘build’ dBA level > design year no-build ____ ____ ____ ____

>5dBA 3-5 0-2 <0dBA

6. Cost per residence benefited ____ ____ ____ ____

<$15K $15-19K $20-25K >$25K

Additional Considerations:

7. Have efforts been made at the local level to prevent

incompatible development adjacent to highways? ____ ____

BARRIER DESIRABILITY:

Do a majority (50% + 1) of impacted residents want a barrier? ____ __

Project Name:_________________________________ Project#______________ Key#_______

EXHIBIT 1300-6 Idaho Transportation Department (ITD) NOISE ABATEMENT DECISION CHECKLIST

DISTRICT/LHTAC DECISION regarding the following receptor(s) ______________________

Yes No

___ ___ A traffic noise impact has been identified [23 CFR 772.13(a)(1)]. (Relative or Absolute)

___ ___ The noise abatement measures will (effectively) reduce the traffic noise impact [23 CFR 772.13(a)(2)].

___ ___ The impacts for which the mitigation is proposed actually result from the Administration action [23 CFR 771.105(d)(1)].

___ ___ The proposed mitigation represents a reasonable public expenditure after considering the impacts of the action and the benefits of the proposed mitigation measures [23 CFR 771.105(d)(2)] & [23 CFR 772.13(a)(1)].

____________________________________________________________

_____Based on the studies so far accomplished, the State/local jurisdiction intends to install noise abatement measures in the form of:

A barrier at ________________________________________________. These preliminary indications of likely abatement measures are based upon preliminary design for a barrier cost of $_______________ that will reduce the noise level by ______dBA for __________ residents.

(Note: If it subsequently develops during final design that these conditions have changed, the abatement measures might not be provided. Any such changes should be documented in a revised environmental evaluation, which must be approved by FHWA. Local agencies must also be notified of changes. A final decision of the installation of the abatement measure(s) will be made upon completion of the project design and the public involvement processes. Also, a barrier should not be rejected for any one single reasonability criterion noted on ‘Barrier Checklist’, unless a majority of impacted residents do not want it.)

____________________________________________________________

_____Based on the studies so far accomplished, the State/local jurisdiction does not intend to install noise abatement measures for the following reasons:

___No project related traffic noise impacts identified

___Abatement measures are not effective

___Project traffic noise is not the dominant noise source

___Abatement measures conflict with the purpose of the project

___Receptors are not considered noise sensitive (ie., commercial, highway business, industrial, etc.)

___Unnoticeable change (<3dBA) in noise level between design year build and no-build alternatives

___Local ordinances allow development along highways without consideration for noise abatement

___Traffic noise impacts are a result of development occurring after the highway was constructed

___Traffic noise impacts resulted from development occurring after the 1976 NAC became effective

___Cost per benefited residence is excessive

___Other, comment:

PREPARED BY___________________________________________________________ DATE_____________

District/LHTAC Environmental Planner/Engineer

EXHIIT 1300-7 CONSTRUCTION NOISE.

[EXAMPLE FOR A ROUTINE PROJECT]

The most prevalent construction noise source is equipment powered by internal combustion engines (usually diesel). Noise from equipment likely to be used on this project (tractors, trucks, graders, pile drivers, etc.) will range to about 95 decibels (dBA) when measured from a distance of 15 meters (50'). To reduce the impact of construction noise, most construction activities will be confined to the period least disturbing to adjacent and nearby residents, between 7:00am and 7:00pm on weekdays. Mitigation of potential highway construction noise impacts shall incorporate low-cost, easy-to-implement measures into project plans and specifications (e.g.; equipment muffler requirements, work-hour limits).

EXHIBIT 1300-8 Highway Noise Analyses.

Sample Scope of Work

The CONSULTANT shall prepare a technical memorandum documenting the methodology and assumptions used to guide the noise analysis.

The CONSULTANT shall conduct a reconnaissance of the project study area to identify all of the land uses and locate noise sensitive properties within ___ feet of the project (to be determined by District/LHTAC) as described in 23 CFR Part 772.

The CONSULTANT shall note physical and terrain features that affect noise propagation and features which may be altered during construction.

The CONSULTANT shall then conduct a noise study for the project area based on the guidelines presented in the current 23 CFR 772 Procedures for Abatement of Highway Traffic Noise and Construction Noise, and the ITD Traffic Noise Abatement Policy and Procedures. Noise measurements will be conducted at sites as needed to calibrate the traffic noise model and to verify the predominant noise source in the project area. Calibration measurements will be conducted for a minimum of 6 minute sampling periods during daytime hours when traffic is moving freely. At each measurement site, traffic counts will be conducted concurrently with the noise measurements. Any noteworthy noise source will be identified especially those that may interfere with future mitigation determination. Traffic volumes that are counted during the noise measurement survey will be modeled and the resulting sound levels will be compared with the measured sound levels to reach close agreement. The use of shielding and alpha factors may be needed to adjust modeled receptor noise levels. Once the model has been calibrated, design hour traffic volumes (DHV) will be used with posted speeds to calculate existing and design year (build & no build) noise levels. In locations where there are no existing roadways, field measurements will be conducted for a minimum 15 minute sampling periods during daylight hours and used to represent the existing noise level.

The CONSULTANT shall model the future year traffic noise level with and without the proposed project using the FHWA Traffic Noise Model (TNM). Noise levels in the design year for each alternative will be modeled at selected noise sensitive receptors based on forecast design hour traffic volumes (DHV). Modeling must be adequate to accurately predict the noise levels at each of the receptors, assess the number of properties that are impacted or will be impacted and determine the increase in traffic noise and amount of reduction to each receptor as a result of mitigation.

In accordance with FHWA and ITD requirements, noise abatement measures will be considered at locations along the alignments where traffic noise impacts are predicted. Mitigation measures considered must include the six measures outlined in 23 CFR 772.13(c).

The CONSULTANT shall provide location, length, height, profile, estimated cost and number of benefited noise sensitive receptors for each proposed barrier. The analysis will contain a complete discussion of impacted areas/receptors that do not meet ITD’s criteria for abatement and specifically note reasons for not including mitigation. The CONSULTANT in accordance with ITD’s procedures will qualitatively assess construction activities that may cause annoyance at nearby noise sensitive land uses.

The CONSULTANT will discuss any local laws applying to construction noise.

Deliverables:

1. Noise Model Data files,

2. Record of field measurements and traffic counts,

3. Noise Analysis Technical Memorandum containing:

3.1. Tables of contents, figures and charts

3.2. A summary including the impacts of each alternative and mitigation recommended

3.3. A map showing centerlines, receptors, R/W lines, zoning, and relevant shielding factors.

3.4. Noise descriptors used in the report

3.5. Discussion of methodology used, including: abatement criteria, noise model, traffic data, speeds, vehicle type percentages and design hour volumes for existing and design year for each alternative.

3.6. Discussion of existing land use including areas of zoning and major terrain features.

3.7. Discussion of existing and future noise levels.

3.8. An impact analysis that includes a table comparing the noise levels at each receiver for existing conditions and the design year for each alternative as well as the number of sensitive residences or other sites represented by each receiver. Analysis and all information (as relevant to the project) as outlined in Section 1300.05 (3). The table should be presented with the type of format shown in Exhibit 1300-3.

3.9. A mitigation analysis that includes a discussion for each impacted area/receptor and proposed mitigation.

3.10. A construction noise section

3.11. Barrier & non-barrier checklists (Exhibits 1300-4, 13006-5)