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UNIVERSITY OF CALIFORNIA, BERKELEY BERKELEY DAVIS IRVINE LOS ANGELES MERCED RIVERSIDE SAN DIEGO SAN FRANCISCO SANTA BARBARA SANTA CRUZ FACILITIES SERVICES BERKELEY, CALIFORNIA 94720-1380 September 26, 2011 TO: City of Berkeley Landmarks Preservation Commission FR: Jennifer McDougall, Principal Planner, UC Berkeley re: Information Item: Hearst Greek Theatre Seismic Safety Corrections Project Background: The Hearst Greek Theatre is one of a very few remaining seismic safety projects to be addressed at the UC Berkeley campus. The Hearst Greek Theatre was designed by John Galen Howard. It opened in 1903, was remodeled in 1957, and was placed on the National Register of Historic Places as part of a multiple listing of significant campus resources in 1977. A 1997 seismic study rated the colonnade structure as seismically very poor. A 2009 feasibility report evaluated two seismic strengthening schemes: a concealed scheme, and an external steel frame exposed scheme. In 2010, UC Berkeley began working with Chris Wasney of Cody Andersen Wasney Architects to complete an historically sensitive seismic design solution. The work has been substantially informed by an historic structure report for the Greek Theatre, completed in 2007 and posted on the web at http://tinyurl.com/ucbgreek. The proposed design has been reviewed with the State Office of Historic Preservation, and meets criteria for an historical resource restoration/rehabilitation. Design Overview: The project will upgrade the seismic rating of the colonnade, and improve life safety and accessibility within the area of work. The project will implement a concealed seismic strengthening scheme, strengthening the colonnade and the retaining walls that confine the western edge of the seating bowl. The area of work does not include the majority of the amphitheater seating bowl, and none of the upper bowl spectator areas and support spaces. The Greek Theatre Seismic Safety Corrections Project will address the structural, fire/life safety, and accessibility deficiencies of select portions of the Greek Theatre. The work will include the following: 1. The end walls of the amphitheater bowl will be seismically braced using tie‐backs and new reinforced concrete footings. 2. The sub‐foundation of the colonnade will be accessed by cutting through the east retaining wall of the existing subterranean structure, new underpinning structure added, and the retaining walls repaired to match the original condition. 3. The existing stage slab will be removed, new foundations with piers installed, and a new stage slab poured back to make the installation match the original condition. 4. The colonnade will be seismically braced using existing voids in the structure to introduced reinforced structural concrete that will tie to new foundation elements under the stage. 5. The colonnade will have the standing seam copper roof removed, a new reinforced concrete tie beam installed, and new standing seam copper roofing installed to match the original condition. 6. The north, west, and south surfaces of the colonnade structure will have a layer of fiber‐wrap reinforcing added to structurally tie the existing concrete infill panels to the existing concrete UNIVERSITY OF CALIFORNIA BERKELEY HEARST GREEK THEATRE SEISMIC SAFETY CORRECTIONS PROJECT columns. 7. All surfaces affected by the structural modifications will have the existing plaster parge coat removed and a new plaster coat applied to match the original condition. Other areas where minor modifications occur will receive a skim coat of plaster. All surfaces of the colonnade backdrop and amphitheater bowl end walls will receive 2 coats of elastomeric paint. 8. The existing two‐stop freight elevator will be removed, the pit waterproofed, and a new double telescoping ram two‐stop passenger/service elevator installed in the existing shaft. 9. The toilet rooms and showers at the subterranean structure will be gutted and rebuilt as fully access compliant toilet rooms and showers. 10. The existing fire sprinkler system will be modified to meet current codes including a new riser system and point‐of‐connection to the high‐pressure water main, seismic bracing, and added lines and heads. 11. The existing fire alarm system will be modified to meet current codes including additional pull stations and horn/strobe devices. 12. The existing mechanical system will be modified to accommodate the structural work. 13. The exterior north ramp and portions of the west plaza will be rebuilt to correct slopes and paving system installed to maintain the historic character of the existing paving. 14. Existing exterior lights will be modified and recircuited and new lights added to provide code compliment exit lighting levels at the north exit stairs and ramp and the south exit stairs and ramps. 15. The existing metal gates and supports at the north and south entry points to the amphitheater will be removed and new code compliant metal gates installed that match the original design. 16. Emergency exit lights and illuminated signs will be upgraded and supplemented to meet code requirements at backstage above grade and subterranean areas. 17. Accessible drinking fountains will be added at backstage above grade and subterranean areas. 18. Associated upgrades to lighting, electrical power, and plumbing to support the above described work. 19. Add alternates will be part of the bid package to address additional scopes of work for added power and data feeds, upgraded mechanical system, additional structural slab reinforcing for anchoring stage production equipment, additional stage lighting, and replacing existing changing room walls with new full height partitions. 20. All work is undertaken equivalent to a LEED/CI Certified construction project but certification will not be pursued. Sustainable aspects of the work include minimization and recycling of construction waste, recycled content in construction materials, water efficient fixtures, energy efficient lighting, indoor air quality preservation, and low VOC coatings and sealants. CEQA Review: The seismic work is consistent with the UC Berkeley 2020 Long Range Development Plan and is exempt from CEQA under Class 31, because it consists of repair, stabilization, rehabilitation, restoration and reconstruction of the Greek Theatre in a manner consistent with the SOI standards. Preliminary schedule: We anticipate construction to begin in November 2011 and last for 150 days. Further questions: Please contact Jennifer with any questions or concerns at (510)642‐7720 or [email protected] Page 2 .