RDA Reso 2000-004 - Laserfiche WebLink

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• NOISE STUDY FOR THE CREEKSIDE CENTER DEVELOPMENT AT SAN LEANDRO BOULEVARD AND DAVIS STREET, SAN LEANDRO INTRODUCTION Environmental Science Associates (ESA) prepazed this noise study to assess the' potential noise impacts of the proposed commercial Creekside Center Development at Davis Street and San Leandro Boulevazd. Assessment of potential noise impacts aze based on noise measurements,. modeling, and attenuation calculations. The proposed development would be located at the northeast corner of San Leandro Boulevard and Davis Street (see Figure 1) on a lot that is currently undeveloped (the project site). The project would include a retail shopping center, totaling 80,904 square feet. Shopping center tenants aze indicated by the city to consist of a 36,000 squaze foot grocery store, up to 14,000 square feet of restaurants/food service, 13,904 square feet of drug store and other miscellaneous tenants. The grocery sore would include an enclosed loading dock. The proposed retail center tenants could operate seven days per week and could potentially operate into the nighttime hours. A drive though window of the proposed pharmacy could operate 24-hours a day. AMBIENT NOISE SOURCES AND LEVELS Environmental noise usually is measured in A-weighted decibels (dBA).1 Environmental noise typically fluctuates over time, and different types of noise descriptors are used to account for this variability. Typical noise descriptors include the energy-equivalent noise level (I..eq) and the day-night average noise level (Ldn).2 The Ldn is commonly used in establishing noise exposure guidelines for specific land uses. 1 A decibel (dB) is a unit of sound energy intensity. Sound waves, traveling outwazd from a source, exert a sound pressure level (commonly called "sound level") measured in dB. An A-weighted decibel (dBA) is a decibel convected for the variation in frequency response of the typical human ear at commonly encountered noise levels. 2 All noise levels reported herein are "A-weighted" decibels. L the energy equivalent noise level (or "average" noise level), is the equivalent steady-state continuous noise lev~l which, in a stated period of time, contains the same acoustic e-+ergy as the time-varying sound level actually measured during the same period. Ld ,the day-night average noise level, is a weighted 24-hour average noise level. With the L descriptor, noise revels between 10:00 p.m. and 7:00 a.m. are adjusted upwards by ten dBA to take into account ~e greater annoyance of nighttime noise as compared to daytime noise. Other descriptors used herein include the maximum noise level (Lm x) and the noise-level-exceeded-X-percent-of--the-time (L ). Two Lx descriptors include the L2 (noise level exceeded two percent of the time) and the L50 (noise level excee~ed 50 percent of the time). ~~~