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HomeMy WebLinkAbout60-05 • Ili 1 1 60-05 RESOLUTION NO A RESOLUTION OF THE CITY COUNCIL OF THE TOWN OF LOS ALTOS HILLS AUTHORIZING EXECUTION OF AN AGREEMENT WITH THE TOWN OF LOS ALTOS HILLS, CITY OF LOS ALTOS AND THE SANTA - CLARA VALLEY WATER DISTRICT FOR NOISE MITIGATION NORTH OF THE WEST EDITH AVENUE BRIDGE AS PART OF THE ADOBE CREEK REACH 5 RESTORATION PROJECT WHEREAS, the City Council of the Town of Los Altos Hills has read and considered that certain Agreement between the Town of Los Altos Hills, City of Los Altos, and Santa Clara Valley Water District to equally fund noise mitigation work as part of the Adobe Creek Reach 5 Restoration Project; NOW THERFORE, the City Council of the Town of Los Altos Hills does hereby authorize the City Manager on behalf of the Town to execute the Agreement between the Town of Los Altos Hills, City of Los Altos, and Santa Clara Valley Water District to equally fund noise mitigation work as part of the Adobe Creek Reach 5 Restoration Project for the 2006-2007 fiscal year. REGULARLY PASSED AND ADOPTED this 7th day of July, 2005. By: 4By: — -- I Mayor ATTEST: .,, � - k _ _ a L:\engineering\COUNCIL ITEMS\2005\0705\Reno Edith Noise Mitigation Agreement 7-7-5.doc • • AGREEMENT FOR SOUND ATTENUATION FROM EDITH AVENUE BRIDGE This Agreement is for the purpose of establishing the terms and conditions for mitigation of sound at the Millar Property located at 400 Cypress Drive, Los Altos, California. This Agreement is between Pauline Lemp Millar (Millar),Peter and Anne Astiz(Astizs),the City of Los Altos (City),the Town of Los Altos Hills (Town) and the Santa Clara Valley Water District (District) collectively referred to as the Parties. RECITALS A. The West Edith Avenue Bridge over Adobe Creek was replaced in 1985 to increase the vehicular capacity, add a pedestrian/bike path and increase the hydraulic capacity. The bridge was raised approximately one foot during construction. B. Under the Cost Sharing Agreement for the construction of the bridge, the Town, City and District shared equally in the costs. The Town was the lead agency for CEQA compliance and for construction of the bridge. C. West Edith Avenue Bridge is within the Town of Los Altos Hills and is maintained by the Town. The District is responsible for maintaining the channel of the watercourse crossed by the bridge. D. The property owner (Millar) north of the bridge at 400 Cypress Drive, Los Altos has indicated that there are noise impacts to her propertyresulting from theloss of trees and raising of the street that occurred during the 1985 bridge project. She has requested that the noise be mitigated. E. A'Noise Impact and Mitigation Study (Study), prepared by H. Stanton Shelly under contract by the District, evaluated the noise conditions and developed noise solutions and mitigation measures. The Study, included as Attachment 1, was presented to the Parties at a special Adobe Creek Collaborative Group meeting on November 30, 2004. During that meeting, a consensus between Millar and the staff of the Town, the City and the District was reached on a noise mitigation alternative. The mitigation includes construction of approximately 143 lineal feet of wood sound attenuation wall for the Millar property. The wall would be located along the back property line adjacent to Adobe Creek and northerly adjacent to West Edith Avenue as shown in Exhibit 3 of Attachment 1. Other sound attenuation work would include removal of the bumps in the asphalt pavement next to the Edith Avenue Bridge approaches. F. On December 16, 2004 the City Council of the Town of Los Altos Hills approved in concept this agreement and authorized the City Manager to fund the Town's contribution. G. On February 8, 2005 the City Council of the City of Los Altos approved in concept this agreement and authorized the City Manager to fund the City's contribution. • Page 1 of 4 AS-r1x- • • H. The Chief Executive Officer of Santa Clara Valley Water District under Board Policy EL-5.7 has the authority to enter into this agreement and authorize funding. Millar and Astizs have dedicated flood protection easements to District and District has proceeded to produce conceptual design alternatives for the Adobe Creek Upper Reach 5 Restoration Project. In consideration of the above,the Parties agree to the terms and conditions as follows: TERMS AND CONDITIONS 1. A wood sound attenuation wall will be built in the Millar's backyard along Adobe Creek and sideyard along West Edith Avenue as recommended in the Study in the same location as the existing fence. The wood sound attenuation wall shall be constructed of double layers of 5/8" or 3/4"redwood, layers offset so there are no cracks after aging,treated with a waterproofing sealer or exterior paint as approved by Millar. Subject to variance approval granted by the City of Los Altos Board of Adjustments to allow the wall heights to exceed 6 (six) feet in height as regulated by the zoning ordinance, the wall heights shall be as follows: A. Along Adobe Creek in the backyard the wall shall be 11 (eleven) feet high at West Edith Avenue rising to 13 (thirteen) feet high at the Levis property line. The length of this section of wall is approximately 68 (sixty-eight) feet. B. Along West Edith avenue in the sideyard the wall shall be 11 (eleven) feet high at Adobe Creek decreasing to 7 (seven) feet high within approximately 17 (seventeen) feet and continuing further for approximately 43 (forty-three) feet at 7 (seven) feet high. C. The wall shall be extended approximately 15 (fifteen) feet northerly to meet the side of the house at 7 (seven) feet high. A gate shall be constructed in this section D. Millar may have more wall constructed than is prescribed in A, B, and C above at her own expense and as long as the wall is in compliance with local, state, regional and federal requirements. 2. The Town, City and District shall share equally the cost for the removal of the existing fence and construction of the wood sound attenuation wall and associated work as noted in Items 1, 3, and 7 as modified, if needed, by Item 11. The total cost shall not exceed $30,000.00 (thirty thousand dollars); $10,000.00 each. 3. The Town shall remove the bumps in the asphalt pavement next to the Edith Avenue Bridge approaches subject to available funds. The bumps shall not be removed until the construction of the sound wall is completed and in consideration of Item 11. Upon removal of the bumps, if performed,the Town shall invoice the City, up to the City's remaining cost share amount established in Item 2, for 1/2 (one half) of the construction cost for removal of the bumps in the asphalt. Payment shall be made to the Town within 90 days. Page 2 of 4 410 • 4. The sound wall maybe built whenever Millar wishes, however payment bythe Cityand p Ym Town shall not be made until the construction of the Adobe Creek Upper Reach 5 Restoration project has been awarded to a contractor by the District. City and Town agree to make payment within 90 days of receiving an invoice from Millar and in accordance with Item 5. 5. Invoices submitted by Millar shall have a breakdown showing the material costs, labor costs and the items constructed that are included for payment by that invoice. Millar shall cooperate with the City and Town with verification of the invoiced items including field confirmation of the wall construction. 6. The City shall process a variance application prepared by Millar for consideration by the Board of Adjustments, as needed, to construct the wall and shall not charge Millar for any City application fees and permit(s) required at time of application. The estimated c)1A4------ application fee are $652 and estimated permit and plan check fees are $645, or$1,297 in total. The cost for application, permit, and plan check fees associated with this Item shal /(t 9 /a: -: :.- .. : :-- - waived by the City of Los Al os. v - e/Vi p� 7. The Study as described in Recital E above has been paid for by the District in the amount Cv Q- of$3,400.00. This amount shall be considered part of the cost-sharing amount for the District established in Item 2. The remaining portion of the District's cost share amount ($6,600) may be paid prior to the construction of the wall upon being invoiced by Millar. 8. The Astizs grant permission to remove theexisting fence and construct a wood sound attenuation wall, as describe herein, subject to the following: (i)by their execution of this agreement, Millar agree to indemnify and hold the Astizs harmless from all costs and liabilities of whatever kind or nature relating to construction of the fence and their use of the portion of the Astizs property on the east side of Adobe Creek that is adjacent to the Millar property. 9 Millar is responsible for all aspects of the construction of the wall and once built is the sole owner of the wall and shall be responsible for its maintenance and replacement as needed. Millar is also responsible for obtaining all permits needed for the construction of the wall. 10. Millar shall obtain 2 bids from licensed contractors for the construction of the wall. The low bid will be the bases for payment of invoices by the City and Town per Item 4. 11. This Agreement does not have any bearing on the ownership of any land nor establishes any permanent easements. However, Millar and the Astizs agree that should they sell their properties prior to completion of the wall,they will notify the buyers in writing about the existence of this Agreement, and obtain a written acceptance from the buyers of the terms of the Agreement. 12. If in the event that the construction bid cost for the wall plus the cost sharing items as mentioned in Items 3, 6 and 7 exceed$30,000,Millar will, at her option, consider Page 3 of 4 1 1 " • • reducing the size of the project, not removing the bumps as described in Item 3, paying for the amount exceeding$30,000 or any combination of any of these options. The Parties, in agreement with the above Items, show their commitment and agreement by signing below: r1VCS 7-27-- � aureen Cassingham ' Date Philip Rose Date City Manager City Manager Town of Los Altos Hills City of Los Altos 26379 Fremont Road One North San Antonio Road Los Altos Hills, CA 94022 Los Altos, CA 94022-3088 3 City A orney a e Jo" ouston Date Town of Los Altos Hills City Attorney City of Los Altos A4\CDC Pauline Lemp Millar, 400 Cypress Drive Los ltos, CA 94022 4: ( Petr Astiz Dat Anne Astiz / Date 13901 W. Edith Avenue 13901 W. Edith Avenue Los Altos, CA 94022 Lo Altos Hills, CAc94022 Williams Date Di s nct Counsel Date Ihief Executive Officer Santa Clara Valley Water District anta Clara Valley Water District 5450 Almaden Expressway San Jose, CA 95118-3614 Page 4 of 4 scvw1) Ac t 'CA 193M • • Attachment 1 Noise Impact and Mitigation Study by S. Shelly • • Environmental Consulting Services 18488 Prospect Road—Suite 1, Saratoga, CA 95070 Phone: (408) 257-1045 stanshe1199@toast.net FAX: (408) 257-7235 NOISE IMPACT AND MITIGATION STUDY Adobe Creek Bridge at Edith Avenue -Traffic Noise Wall 400 Cypress Drive Los Altos, California November 29, 2004 Submitted to Santa Clara Valley Water District San Jose CA Prepared by H. STANTON SHELLY Principal Consultant Adobe Creek/West Edith TratNoise Study-Los Altos I Page.1 of 6 I. Project Description The Santa Clara Valley Water District has a plan for improvements along Adobe Creek in Los Altos near the West Edith Avenue bridge. This project may provide an opportunity make modifications near the bridge and the adjacent Millar property at 400 Cypress Avenue to reduce noise from traffic on West Edith. The bridge was constructed in 1985 and was a joint project of the Town of Los Altos Hills • (Town),City of Los Altos(City), and the Santa Clara Valley Water District(District). Design and construction of the bridge, as well as CEQA review,was completed by the Town of Los Altos Hills. Funding for bridge construction was primarily provided by a federal grant. The remaining cost was shared equally between the City,Town and District. Bridge construction required the removal of large eucalyptus trees. The existing wooden fence on the Millar property next to the creek and the road is about 9 feet high relative to the lowest part of back yard,but because the elevation of the base is very low,the effective height of the fence relative to the roadway is only about 3 feet. From the backyard patio of 400 Cypress vehicles on West Edith can be seen above the top of the fence, so this also indicates a direct path from vehicles to the patio and very little noise reduction. In addition,the present wood wall has cracks and openings that allow noise to penetrate. Hence a key element in reducing the traffic noise level on the Millar property is a taller and more substantial wooden wall. This and other methods of reducing traffic noise levels are discussed in the following sections of the report. II. Existing Setting Noise Sources in the Area The primary source of noise at the project site is traffic on West Edith Avenue, a two-lane arterial that crosses Adobe Creek adjacent to the Millar property(see accompanying Exhibit 3 map). Typical vehicle passby noise levels are in the 55-60 dBA range at on back patio of the property. Trucks, buses,motorcycles, and poorly muffled vehicles produce peak levels 5 to 15 dBA higher on passby. There are no other significant noise sources in the project area. The area is predominantly single family residential in the area, except there is a Los Altos Hills community park located across West Edith Avenue and the creek. Ambient Noise Monitoring Field noise measurements,about 20 minutes at each location,were made between 8:30 and 9:30 am on October 21, 2004,with a CEL-440 Precision Noise Meter and Analyzer, calibrated with a B &K Model 4230 Sound Level Calibrator. The measurement locations were chosen to represent the key sensitive receptor locations on the Millar property, as described below: See accompanying description of typical noise sources and sound levels in Exhibit 4. Noise Monitoring Locations Project noise measurement locations were as follows: • Location 1 —.on the back patio of the residence at 400 Cypress Avenue, approximately 80 feet from the roadway • Location 2—at the low point of the back yard(about 6 feet below road level), and about 25 feet from the 9-foot fence, approximately 60 feet from the roadway. Existing Noise Levels Noise levels were measured and are reported using percentile noise descriptors, as.follows: L90 (the background noise level exceeded 90 % of the time),L50 (the median noise level exceeded 50%of the time),L1 (the peak level exceeded 1%of the time), and Leg(the average energy-equivalent noise level). Measured noise levels are presented in Exhibit 1 on the next page. The CNEL/Ldn noise levels were Environmental Consulting Services * Saratoga Adobe Creek/West Edith Tra•oise Study—Los Altos S Page 2 of 6 computed asthe long-term average of the Leq using typical daily traffic distribution in the area,with standard weighted penalties for the nighttime hours,and modeled with an enhanced version of the National Cooperative Highway Research Board traffic noise model [3]. The noise levels at the second location are lower because of the increased protection of the wall; that is,there is no direct noise transmission to this location as there is on the patio. Bumps in the road around the bridge cause noticeable noise when a vehicle passes,-particularly larger vehicles such as trucks. Exhibit 1 —Existing Noise Levels (dBA) 400 Cypress Avenue—Los Altos Location L90 L50 Leq L1 CNEL 1.Patio 45 52 54 63 56 2.Low part of back yard '41 48 51 59 52 Los Altos Land Use Standards for Noise Compatibility Exhibit 2 presents the general noise planning guidelines adopted in the General Plan of City of Los Altos(revised 2002). Comparing the site noise monitoring described in Exhibit 1 and the Exhibit 2 Planning Guidelines,the site meets the general noise guidelines for residential use,with CNEL values in ' the 50-60 dBA range,and is typical of many residences in Los Altos adjacent to an arterial road,at least in an unprotected location such as a front yard without a fence. Exhibit 2—City of Los Altos Land Use Compatibility Standards [2] Land Use • Normally Acceptable Community Noise Exposure dBA,CNEL Residential 60 Motels,Hotels 60 Schools,Libraries,Churches 60 Playgrounds,Parks 70 Office, Commercial _ 65 Industrial,Manufacturing,Utilities .70 The.Millar property is in direct line of West Edith traffic coming from the west,but it is without protection offered by a fence with an effective height of at least 6 feet. III. Recommended Traffic Noise Mitigation Measures Because background noise levels in the project area are relatively low,while noise levels in the Millar backyard are relatively high that is,without the typical protection from traffic noise in a backyard environment,the following mitigation measures are suggested to reduce noise impacts associated with West Edith Avenue traffic. The following mitigation measures are independent and so the reductions are cumulative. In general, a noise level reduction of 3 dB in this situation would be equivalent to moving the road awayfrom the receptor by50 feet, and a 6 dB reduction would be equivalent to moving the road 100 P feet. Environmental Consulting Services Saratoga Adobe Creek/West Edith Tra Noise Study—Los Altos S Page 3 of 6 1. Replace Existing Fence. Remove existing poor quality fence and install a new wood wall that is higher and thicker. Location: along Adobe Creek and West Edith Avenue—in the same location along south side of Millar back yard,400 Cypress Drive,Los Altos. Possible extension: 85 ft along creek on south border of adjacent Levis property. This extension would reduce theamount of noise from the roadway that goes around the end of higher wall section and reaches the backyard of subject property. Construction: Double layers of 5/8"Redwood The main part of the new wall on the Millar property line would provide a traffic noise reduction.of 3-4 dBA at the key patio location,and the Levis extension could provide another 1-2 dBA. 2. Fix Roadway. Smooth a number of bumps in the roadway around the bridge and resurface the bridge surface and street surface with quiet rubberized materials within at least two hundred feet in each direction.. This surface modification could provide a reduction of 2-3 dBA in tire/surface noise. 3..Trim Broadleaf Foliage. Cut back any broadleaf trees and bushes that extend above the top of the noise wall to prevent tire/surface noise being reflected over the wall by the leaves. Thinner foliage of evergreen trees and bushes do not reflect tire/surface noise significantly and can remain in place. This measure insures that the benefit of the wall is not compromised by noise reflecting over it. IV. Estimated Wall Costs Description of Recommended Wall The following is a more detailed description of the recommended wall project as submitted to several local wall and fence contractors,requesting that they provide an estimate of the construction costs. The wall would completely replace the existing wood fence with a new wood wall that is higher by at least four feet along the roadway and is double thickness to minimize noise transmission through it. • new gate at side of Millar house • 40 ft. section along the side of Millar house—7 feet high • 20 ft. section from side of Millar house down to low back yard elevation—7 to 11 feet high • 70 ft. section along creek on Millar property to Levis property line— 11 to 13 feet high • Possible extension: 85 ft. section along creek,rear of Levis property— 13 feet high • Construction: double layers of 5/8"Redwood, layers offset so there are no cracks after aging Contractor Estimates Four key San Jose fence and wall contractors and one general contractor that works a lot in Los Altos were contacted to provide an estimate of the costs to remove the existing fence and construct a new double wood wall. It was made clear that without an engineering design and specs for the wall we did not expect detailed bids,but merely general estimates of the costs of construction,both for the Millar property and also an extension along the rear of the neighboring Levis property to the west. Two major fence contractors responded, as shown below,while two other fence contractors and the general contractor declined to submit estimates at this time. The wall estimates are as follows: 1. Squires Lumber and Fence—809 N. 13th Street, San Jose, CA 95112; (408) 971-9663, CA License: 567277 Environmental Consulting Services Saratoga Adobe Creek/West Edith Tra•Noise Study—Los Altos • Page 4 of 6 • Estimate: Primary Millar portion: $12,000. Levis extension: $11,000. 2. Sierra Lumber and Fence— 1711 Senter Road, San Jose, CA 95112; (408)286-7071, CA License:299832 Estimate: Primary Millar portion: $38,000. Levis extension: $30,000. V. _REFERENCES 1. Project Site Drawing—"Adobe Creek—Reach 5", SCVWD, San Jose, Sept.30,2004. 2. "Land Use Compatibility Guidelines-Noise",City of Los Altos General Plan,November 2002. 3. Highway Noise-A Design Guide for Highway Engineers,National Cooperative Highway Research Program Report 117,Highway Research Board,National Academy of Sciences, Washington,D.C., 1971 (model enhanced and field validated by ECS). • Environmental Consulting Services * * • Saratoga • i, .Adobe Creek/West Edith Traffic Noise Study—Los Altos Page 5 of 6 Exhibit 3-Project Map(1"=20') '� s2 � 1 I \� `... • • - • i \\ ftp \ t \ �� . / \ • op : � ss • V •• '• \ _i..........••...............•.••.•.••....—.....-.-..•.•.••.•..•...•- ..............Retaining -ii'y/ �o F�•J�4.c� ._. i�G- ';0;ON' Retaining Conc Wall •\ .,.il .. ' Z _,r '...��uf//ham.\ r _ - " ��,� �_ . tt' • -'/ 1�1111 ..4. -.41P --•,---- � 1 .1i„.:, w � s Gu 'te . X340 J�� Sd �F! �����.,:,. Qty p ��1. - �*L; - .� ' i ti\ `: 530 • �e/� •O„ Ill\�' t.G'.,, 9 ',no' /111111.--41111161111'; --"'vta �I� "•i•C�;;/. / r . :4:i 0 ,,:t• I • ' k :i.- .fig,..-..-- \ -2...- ' ,, / t •ape ___�_•-.._ 1 ,l Oil -} %� D\ *it 1' 4_ et ! . . .41.116 itt (fiIIID,4;Z. 11Ali\ / 1 _ ✓. / -I• a ,�� < , �:sj iii\': i r` .. �- i • ' ' 110 Adobe Creek/West Edith TraiNoise Study—Los Altos Page 6 of 6 Exhibit 4 Typical Noise Levels Noise Sources Continuous Noise Human Response or Impact Level(dBA) Jet aircraft takeoff(50') 130 Auto horn(3') 120 Deafening Rock music in a night club 110 105 Single-event possible permanent hearing damage Motorcycle accelerating,no 100 muffler(25') 95 Temporary hearing loss Motorcycle accelerating, stock 90 muffler(25') Food blender(3') 80 Very disturbing to most activities Power lawn mower(20') Steady urban traffic(25') 70 Normal conversation(3') 60 Communications difficult Daytime street,no nearby traffic 50 45 Sleep disturbance Quiet office 40 Inside quiet home. Soft whisper 30 Very quiet (10') Movie or recording studio 20 Seldom-experienced ambient 10 Barely audible to good hearing Threshold of hearing 0 Environmental Consulting Services Saratoga