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New MnDOT noise policy for Type I federal-aid projects

 

 

 

Implementation is triggered by the start of the NEPA process:

      1. Start of NEPA on or after June 1, 2011: Use the new noise policy.
      2. Start of NEPA prior to June 1, 2011: If noise analysis is started* prior to July 13, 2011 use old noise policy.
      3. Start of NEPA prior to June 1, 2011: If noise analysis is started** after July 13, 2011 use new noise policy.


*“Start of noise analysis” is indicated by the completion of at least one noise model run: i.e., there is (or is not) a feasible noise abatement measure for those impacted receptors that also meets the $3250/dB/residence cost effectiveness threshold.
**July 13, 2011: Implementation date of final Federal Rule.

 

 

 

Old MnDOT noise policy for Type I and Type II federal-aid projects as per 23 CFR 772

 

Purpose:

 

The document sets forth procedures for noise studies and noise abatement measures to help protect the public health and welfare, to supply noise abatement criteria, and to establish requirements for information to be given to local officials for use in the planning and design of Federal-aid highways approved pursuant to Title 23, United States Code (U.S.C.).

 

Authority: 23 U.S.C. 109(h), 109(I): 42 U.S.C. 4331, 4332; and 49 CFR 1.48(b).

 

Definitions:

 

Existing noise level The highest hourly noise level caused by existing conditions in a particular area.
Future noise level The highest hourly traffic noise level predicted using the noise model named "Minnoise", or a methodology approved by Mn/DOT. The traffic volumes used for the prediction shall be traffic volumes expected to occur 20 years after the completion of a new highway facility.
L10 The sound level that is exceeded 10 percent of the time (the 90th percentile) for the period under consideration.
L10(h) The hourly value of L10.
L50 The sound level that is exceeded 50 percent of the time (the 50th percentile) for the period under consideration.
L50(h) The hourly value of L50.
Noise barrier Any device, which reduces the transmission of highway traffic noise from a highway to an adjacent receptor, including, but not limited to, earth berms, walls made from timber, metal, concrete, or any combination thereof.
Noise level The sound level obtained through use of A-weighting characteristics. The unit of measure is the decibel (dB), commonly referred to as dBA when A-weighting is used.
Receptor An outdoor place where frequent human use occurs and a lowered noise level would be of benefit.
Residence The official location of a household.
Retrofit project A proposed project for the construction of noise barriers along an existing highway.
Type I Projects A proposed Federal or Federal-aid highway project for the construction of a highway on new location or the physical alteration of an existing highway which significantly changes either the horizontal or vertical alignment or increases the number of through-traffic lanes.
Type II Projects A proposed Federal or Federal-aid highway project for noise abatement on an existing highway. Essentially a retrofit project

 

Information and Clarification:

 

  1. Mn/DOT is in the position of having to deal with two sets of noise level limits that determine what noise levels are acceptable and what noise levels are unacceptable. Table 1 (pg. 4) lists Minnesota's noise level standards. Table 2 (pg. 5) lists the FHWA's noise abatement criteria. Also, no standards adopted by any state agency for limiting levels of noise in terms of sound pressure which may occur in the outdoor atmosphere shall apply to (1) segments of trunk highways constructed with federal interstate substitution money, provided that all reasonably available noise mitigation measures are employed to abate noise, (2) an existing or newly constructed segment of a highway, provided that all reasonably available noise mitigation measures, as approved by the commissioners of the department of transportation and pollution control agency, are employed to abate noise and (3) except for the cities of Minneapolis and St. Paul, an existing or newly constructed segment of a road, street, or highway under the jurisdiction of a road authority of a town, statutory or home rule charter city, or county, except for roadways for which full control of access has been acquired. On Federal-Aid Highways the FHWA noise abatement criterion for category C supersede Minnesota's noise level standards in industrial areas, as they're lower (FHWA NAC 75 dBA versus Minnesota's standard 80 dBA). The FHWA interprets their noise abatement criteria as guideposts for the need of noise abatement, rather than absolute and definite limits. Minnesota's noise level standards are regarded as absolute limits which carry the weight of law. Due to the guidepost interpretation of their criteria, the FHWA requires that states give numerical meaning to the phrase "approach the criterion". Mn/DOT defines a level as "approaching" the criterion level when it is 1 dBA, or less, below the criterion level

 

Applicability:

 

  1. The provisions of this policy shall apply to all Federal-aid highway projects under the jurisdiction of Mn/DOT.
  2. This policy is to be applied so as to avoid conflict with obligations of Mn/DOT to comply with criteria and standards of federal agencies for obtaining and using federal funds.
  3. Future development shall be considered as planned, designed and programmed on the date of Plat Approval, contingent on Mn/DOT having had ample opportunity to do a plat review in order to anticipate possible Federal-aid highway project noise impacts.

 

Noise Barrier Criteria and Policies:

 

  1. Noise barriers shall be designed to provide protection primarily to receptors located in outdoor areas.
  2. For Mn/DOT to consider constructing noise barriers (Type I) on new Federal-aid highway projects or projects where major reconstruction is planned, the following criteria shall be met:
    A) The receptors shall have predicted future noise levels which exceed the levels in Table 1 (except for Industrial areas where FHWA category C criteria in Table 2 apply) or exceed existing noise levels by 5 dBA or more.
    B) The cost effectiveness of the barrier shall not exceed $3250/dBA/residence in 1997 dollars for residential receptor's. A receptor's inclusion in the cost effectiveness calculation shall be contingent on the receptor receiving a minimum 5 dBA reduction due to the construction of the barrier. Mn/DOT may annually adjust this cost effectiveness figure up or down based on changes in the construction price index after 1997.
    C) The barrier project shall have been found feasible and reasonable using Mn/DOT's rating system. (See attachment 1)
  3. For Mn/DOT to consider a location for retrofit (Type II) noise barrier construction, the location shall meet the following criteria:
    A) The receptors shall be exposed to existing noise levels which exceed the levels in Table 1 (except for Industrial areas where FHWA category C criteria in Table 2 apply).
    B) The receptors shall have been ranked and included on Mn/DOT's retrofit barrier priority list (dated 2/1/97) compiled for the state legislature.
    C) The noise barrier(s) are proposed along lands where land development or substantial construction predated the existence of any Federal-aid 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 on new location.
    D) The cost effectiveness of the barrier shall not exceed $3250/dBA/residence in 1997 dollars for residential receptor's. A receptor's inclusion in the cost effectiveness calculation shall be contingent on the receptor receiving a minimum 5 dBA reduction due to the construction of the barrier. Mn/DOT may annually adjust this cost effectiveness figure up or down based on changes in the construction price index after 1997.
    E) The barrier project shall have been found feasible and reasonable using Mn/DOT's rating system. (See attachment 2)

 

Table 1

Minnesota Pollution Control Agency

State Noise Standards

Land Use Code

Day (7:00 a.m. - 10:00 p.m.)
dBA

Night (10:00 p.m. - 7:00 a.m.)
dBA

Residential NAC-1
L10 of 65*
L50 of 60
L10 of 55*
L50 of 50
Commercial NAC-2
L10 of 70
L50 of 65
L10 of 70
L50 of 65
Industrial NAC-3
L10 of 80
L50 of 75
L10 of 80
L50 of 75

* To see exceptions, refer to the Information and Clarification paragraph on page 2.

 

Table 2

Federal Highway Administration Noise Abatement Criteria
Category L10 dBA Land Use
A
60
Special areas requiring serenity
B
70
Residential and recreational areas
C
75
Commercial and industrial areas
D
NA
Undeveloped areas
E
55*
Residential, hospitals, libraries, etc.*

 

(* Applies to interior noise levels. All other land uses are exterior levels)

 

Local participation:

  1. Mn/DOT shall ensure local participation in the locating of noise barriers through the following:

    A) Public notification of proposed Federal-aid highway construction be sequent to the NEPA process being completed, that a public hearing has occurred or municipal approval of a staff approved geometric layout has occurred.
    B) Mn/DOT shall hold one or more informational meetings in the municipality(s) affected by the proposed noise barrier, to provide an opportunity for local participation in the selection and development of the noise barrier installation project. Mn/DOT shall give the highest consideration to the concerns and noise reductions of persons owning or leasing residences in the 1st row and possibly, if determined necessary by Mn/DOT, the 2nd row of affected residences.
    C) For a proposed noise barrier project to be considered for construction, the local government, prior to completion of the final design of a proposed noise barrier, shall furnish Mn/DOT with:
    1. A formal city council resolution supporting the proposed barrier project or a city council approval of a staff approved layout.
    2. Documentation of its land use controls which:
      a) Apply to land adjacent to Federal-aid highways,
      and

      b) Would reasonably eliminate the need for state-funded noise barriers in highway rights-of-way adjacent to future developments.

    Informing of Local Officials:
    1. Mn/DOT informs local officials of the best estimation of future noise levels for both developed and undeveloped lands or properties in the immediate vicinity of a project by means of the environmental documentation process (EIS, EA, Plat reviews), public hearings, public information meetings and direct contact.

    2. Mn/DOT informs local officials of anticipated highway traffic noise levels that will be useful in keeping future land development from becoming incompatible with existing and future highways because of traffic noise by means of the environmental documentation process (EIS, EA, Plat reviews) and direct contact.

    3. Mn/DOT informs local officials of the eligibility requirements of Mn/DOT (See Attachment 2) and the FHWA whenever a Type II project is being considered on a Federal-aid highway.

 

Program:

 

Mn/DOT, upon receiving an individual's/community's request for construction of a retrofit noise barrier, shall check to see if the location appears on the legislative priority list (dated 2/1/97). If the location is on the list it will be dealt with in the order of its ranking and as available funding allows. If the location is not on the priority list, Mn/DOT will decide whether or not to evaluate and rank the noise barrier project. Mn/DOT's decision of whether or not to evaluate and rank a location will depend on several factors. Factors considered in this decision include, but are not limited to, safety considerations, access control, available right-of-way, highway type, construction feasibility, estimated cost of the project, date of adjacent development along the proposed location, traffic noise levels, number of benefiting receptors, community acceptance of the proposed noise barrier, and predicted noise level reduction.