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Home My WebLink About08/03/1993, C-6 - SEISMIC SAFETY CORRECTIONS TO THE 955 MORRO BUILDING ,111111IVIIIII1II�I�� city of San 1�.:b- o81Spo fiffieffiftoda COUNCIL AGENDA REPORT Seismic Safety Corrections to the 955 Morro Building page 2 postponed indefinitely, the 955 Morro Building will house the Public Works and Utilities staffs for several more years and is subject to seismic hazard mitigation under the City's unreinforced masonry ordinance. Also, brainstorming sessions with Stup's project engineer revealed that structural corrections would probably not require vacating the building and would probably cost between $100,000 and $150,000 -- much less than Degenkolb's estimate. With this in mind, staff asked Stup to submit a proposal for analyzing the 955 Morro Building and preparing construction documents for any corrections recommended. Working from this proposal, staff drafted an amendment to the existing agreement for engineering services, and on September 1, 1992, the Council approved that amendment. Proposed Building Improvements. Stup prepared a design based on the 1991 Uniform Code for Building Conservation, which the City adopted without amendments as its standard in January 1993. The construction documents call for three major building improvements: 1. Installing steel frames to reinforce two of the wooden post-and-beam structures which span the building interior. 2. Attaching steel columns to the south and east unreinforced masonry walls to prevent deformation. 3. Anchoring the roof framing system to the exterior walls in order to limit movement of the unreinforced masonry walls. For three reasons the proposed design serves as a positive example for compliance with the City's unreinforced masonry ordinance. First, it shows that corrective work can be esthetically unobtrusive and may not radically alter unreinforced masonry buildings with open storefronts. It also shows that construction activity can be accomplished without extended disruption to building occupants. And finally, it demonstrates that required seismic safety improvements can be built at reasonable cost. The estimated construction cost is about $17.00 per square foot, which is below the $20.00 per square foot average estimate reported by owners of other unreinforced masonry buildings in San Luis Obispo. Consequences of Not Taking the Recommended Action. Without the recommended corrections, the 955 Morro Building would probably suffer severe structural damage in a major earthquake, with devastating consequences for the community. If the building were occupied, there would probably be injury and loss of life. Valuable equipment and vital records would be damaged or destroyed. Also, because the existing building would probably not be safe to occupy after a major earthquake, the Public Works and Utilities staffs could not provide essential services during and after the disaster, like coordinating infrastructure repairs and issuing needed permits. Two cases from the 1989 Loma Prieta earthquake illustrate the danger of not preparing for a c-6- �u►i��H►IVllllll�l�h ��l� city of San t; 3 osispo COUNCIL AGENDA REPORT Seismic Safety Corrections to the 955 Morro Building page 3 major earthquake. In the first instance involving the City of Oakland, several city offices located in an unreinforced masonry building were severely damaged by the earthquake. Fortunately, no employees were killed or injured since the earthquake struck after working hours. But the destruction of records and equipment and the relocation of staff delayed relief and repair efforts for months after the original disaster, because legal documents could not be drawn up and checks could not be issued. In the second example, the Ford department store chain lost two large unreinforced masonry stores in Santa Cruz County, and two customers were killed. Trying to reconstruct these buildings and fight lawsuits started a series of events which led to Ford's decline and bankruptcy. CONCURRENCES: The Acting Utilities Director, whose staff occupies the 955 Morro Building, concurs with the recommendations of this report. The Chief Building Official finds that the design concept follows the technical standards in the unreinforced masonry mitigation plan, and he concurs with the recommendations of this report. FISCAL EMPACT: Budget. The Capital Improvement Plan of the 1991/93 Financial Plan (pages E-10 and E- 23) designated $424,000 for the Seismic Safety Corrections project. Beginning Budget $424,000 Design (62,873) City Hall Basement Construction (35,338) Fire Station 2 Construction (56,622) Fire Station 3 Construction (13,300) Budget Remaining $255,867 Cost Estimate: 955 Morro Building Construction $100,000 Contingencies 7.000 Total $107,000 Project Feasibility. Does it make financial sense to spend $107,000 on seismic safety corrections for the 955 Morro Building? Answering that question requires examining the costs of three general options: 1) constructing the seismic safety corrections 2) building 6,000 square feet of new office space and 3) renting 6,000 square feet of equivalent office space. This line of reasoning assumes that if the seismic safety corrections were not completed, then C-�-3 1111 ih$llllf N1111 city of San IL-S OBISpo Hia; COUNCIL AGENDA REPORT Seismic Safety Corrections to the 955 Morro Building page 4 the 955 Morro Building would have to be vacated eventually, and there would be no existing City facilities suitable for the Public Works and Utilities Departments. (The existing Fire Station No. 1 has extensive seismic safety problems that would not be cost-effective to repair. The retail portion of the Marsh Street Parking Garage, formerly occupied by Riley's, brings in a minimum of$120,000 annually in rental income, which would be lost if the City evicted the tenants.) The following calculations show the annual costs of the three options mentioned. These calculations do not consider opportunity cost or inflation, which would only compound the the simple cost differences. Assuming the City will use the 955 Morro Building for 15 more years, the annual amortized cost of constructing the seismic safety improvements would be $7,100 ($107,000 divided by 15 years). Building 6,000 square feet of new office space on City-owned property would cost about $600,000 (6,000 square feet X $100.00 per square foot). Assuming such construction would be debt-financed, the annual debt service would be $43,300 ($600,000 plus $30,000 financing costs @5.5% for 30 years). The annual cost of renting 6,000 square feet of equivalent office space would be about $797200 (6,000 square feet X $1.10 per square foot per month X 12 months). Building the seismic safety corrections is by far the least expensive way to provide safe and convenient quarters for the Public Works and Utilities staffs. Plans and specifications are available in the Council Office for inspection. G:1WP511sE1sMIC6 C-�O-