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REPORT TO SHASTA COUNTY RTPA

RECOMMENDATION
It is recommended the RTPA request that Caltrans develop soundwall projects for future RIP funding consideration.

SUMMARY
Recently the RTPA and Caltrans received several complaints about vehicle traffic noise originating from Interstate 5. Complaints have been received from an area generally running north from Bonnyview to Twin View Blvd. The first step to addressing this issue is to direct Caltrans to develop soundwall projects for funding consideration.

DISCUSSION
Generally, soundwalls are a form of a noise barrier that are used in areas that exceed certain noise thresholds as a way to reduce the impacts of this noise in the areas surrounding the freeway. They can be solid obstructions built between the highway and the homes along the highway. Effective noise barriers can reduce noise levels by ten to fifteen decibels, cutting the loudness of traffic noise in half. Barriers can be formed from earth mounds along the road (usually called earth berms)or from high vertical walls. Soundwalls can be built out of wood, stucco, concrete, masonry, metal, and other materials.

Under SB 45 guidelines RTPA's may request that Caltrans develop projects for Regional Improvement Program (RIP) funding consideration. Soundwalls are considered an eligible project for this funding source. To ensure that soundwall projects receive due consideration from the Agency it is recommended that the RTPA make this request to Caltrans.

SOUNDWALL FUNDING SCENARIOS
Historically, soundwalls have been constructed by Caltrans under six basic programs for residential areas:

1. As part of a new freeway project;
2. As part of a freeway widening project;
3. Under the School Noise Abatement Program;
4. Under the Community Noise Abatement Program.
5. Under the State Highway Operation and Protection Program (SHOPP); and
6. As part of the State Transportation Improvement Program (STIP)

In regards to items 1 and 2 above, they are not part of this discussion as the comments received do not pertain to construction of a new freeway or freeway widening project.

The School Noise Abatement Program is required based upon Streets and Highway Code Requirements Section 216. It requires Caltrans to mitigate noise that intrudes into specified areas within public and private, elementary or secondary schools when that noise is generated by freeway traffic or by the construction of the freeway. The areas eligible for protection from the noise are those which are used as classrooms, libraries, multipurpose rooms and spaces used for pupil personnel services. When the levels within these areas exceed 52 dBA, Leq., Caltrans is required to reduce the excessive noise. The Code establishes qualifying criteria that include the time of school construction and current use of the school. According to Caltrans Project Development Procedures Manual Chapter 30, Section 4; "Projects under these criteria should be proposed as SHOPP projects, as there is no longer a program specifically for school noise abatement. Noise abatement options include construction of a noise barrier, acoustical treatment of the school structure, or a combination of both."

The Community Noise Abatement Program funds most of the construction of soundwalls using STIP funding sources. This program is designed, for the most part for the construction of soundwalls along existing freeways in residential areas where three criteria are met. The three criteria are:

1. The noise level must exceed a threshold of 67dBA (Leq). In an area frequently used by people.
2. Noise Mitigation must be designed to reduce the noise level at least 5 decibels.
3. Projects must be cost-effective. Projects costing no more than $35,000 per residential unit protected by the barrier are considered cost- effective.

In regards to 5 and 6 above, SHOPP and STIP are the funding mechanisms used to program the improvements to correct the problem.

CURRENT CONDITIONS
Recently, complaints from the public were received regarding noise levels specific to areas adjacent to I-5. I-5 is considered Caltrans jurisdiction. The comments received from the public, for purposes of this report, are categorized as the South and North areas. These study areas can be best described as South area, Churn Creek/Bonnyview to Cypress, and the North area, Highway 299 interchange north to Twin View Blvd. The southern comments also expressed concern about noise on behalf of Parson School.

SOUTH AREA CONDITIONS
Based upon the complaints reported, Caltrans prepared a special study on six segments of I-5 in January 2002. The segments and test results in the South study included;

• Segment 1, North Bound I-5 from Churn Creek Road overcrossing (OC) to Loma Vista. The average noise level in segment 1 is Leq 75 dBA
• Segment 2, South Bound from Hartnell overcrossing to Loma Vista OC. The average noise level for this segment is Leq 72 dBA
• Segment 3, North bound I-5 from Loma Vista OC to Hartnell OC. The average noise level for this segment is Leq 70 dBA
• Segment 4, South Bound I-5 from Cypress Undercrossing (UC) to Hartnell OC. The average noise level for this segment is Leq 73 dBA
• Segment 5, North Bound I-5 from Hartnell OC to Cypress UC. The average noise level for this segment is Leq 70 dBA
• Segment 6, South Bound I-5 from Loma Vista OC to Churn Creek OC, per the report there are no sensitive receptors adjacent to the freeway in Segment 6.

The test results indicate the level of noise is greater than the 67 dBA standard. Soundwalls in these segments would be eligible for funding. Assuming adoption of the Staff recommendation, it is expected that Caltrans will nominate eligible soundwall projects in this area for RIP funding consideration

Additionally, based upon a request from the Prettymans' (letter attached) in the south study area, Caltrans performed a special study at their location to derive measurements of the "adjusted worst-hour noise level." The study results indicated readings from a low of 44 dBA to a high of 58 dBA at their home which is approximately 1,000 feet from the freeway in segment one.

NORTH AREA CONDITIONS
At this time the most recent data related to noise in this area is a study conducted in 1993. In order to better define the noise in the North study area, the RTPA could request that Caltrans conduct a study to collect noise measurements between the interchange of Highway 299 and Constitution Way. The noise study may not be needed as we can infer that the noise levels in the adjacent segments speak for the more northern segments and the 1993 Caltrans study indicates a dBA level of 70 for that segment. Funding for the region is scarce, so the use of funds for the sake of measurement of a known problem may not be the best use of resources.

Given the results of the 1993 noise study it is clear that this area also qualifies for soundwall funding. Assuming adoption of the Staff recommendation, it is expected that Caltrans will nominate eligible soundwall projects in this area for STIP funding consideration

A concerned citizen in this area, Vivian Brant has expressed some safety concerns in this area unrelated to noise. She also presented to the Agency at the February a petition signed by about 100 neighbors requesting attention to their perceived safety problems. The concern is that there is an unsafe condition from the northbound on ramp at SR 299 to the northbound off-ramp on I-5 at Twin View Blvd. Recent correspondence from Caltrans to Mrs. Brant indicated a review of the accident history along the segment was undertaken. Based upon that analysis the segment of freeway studied is not a candidate for placement of guardrail or other means of a safety barrier at this time.

ALTERNATIVES
An identified alternative to the Staff recommendation would be to not request that Caltrans develop projects for future RIP funding consideration. This is not recommended because these areas meet the standards for noise mitigation.

OTHER AGENCY INVOLVEMENT
This matter was discussed with Caltrans personnel, in particular the RTPA should recognize Mr. Mark Miller, Chief of Advanced Planning for sharing his knowledge of the situation and leading the special studies that defined the problem and ensured the accuracy of the study results. This matter was also discussed at the April 9, 2002 TAC meeting with all agency members.

Caltrans has indicated that these projects can be developed easily for future funding consideration.

FINANCING
With the exception of soundwalls near schools all other soundwall projects are generally funded from the RIP program. If the Staff recommendation is adopted then it is expected that Caltrans will nominate soundwall in these areas for funding consideration the next time the RTPA issues a call for projects. Funding for soundwall near schools may originate from the SHOPP program. Since a complaint specific to the School Noise Abatement Program has not been received, it is uncertain if these would qualify for funding at this time. In any event projects of this type are the sole responsibility of Caltrans as the owner-operator of the system.

________________________________
Daniel J. Kovacich, Executive Officer

tlh/jac

Attachments:

1) Letter from Mr. and Mrs. Prettyman dated February 20, 2002 to Dan Kovacich
2) Letter from Dan Kovacich dated March 5, 2002 to the Prettymans
3) Letter from Brian Crane dated March 21,2002 to the Prettymans
4) Letter from Vivan Brant dated Feb. 22, 2002 to Mark Miller
5) Letter from Caltrans dated April 2, 2002 to Vivan Brant
6) Letter from Mark Miller dated January 31, 2002 to the Prettymans