THE LAND BENEATH San Francisco's financial district, which is regularly shaken by earthquakes, was at one time under the waters of San Francisco Bay. Thus the district, jammed with high-rise office buildings, hotels, commercial buildings and people, is built on loose fill dotted with random debris. By the 1980s, transportation in the area had become problematic: despite service by MUNI busses, MUNI Metro, and the Bay Area Rapid Transit (BART) system, vehicular traffic was congested, public transportation was filled, and there was a bottleneck at the end of the MUNI Metro line.
The City launched the MUNI Metro Turnback Project (MMT) in 1985 to increase the capacity of the MUNI Metro at the existing terminus and provide for future Metro expansion at street level beside the Bay. The project consisted of design and construction of twin steel-lined tunnels 840 feet long and 18 feet in diameter, extending from the Embarcadero Station under Market Street and Justin Herman Plaza, to connect with a concrete box structure 1,120 feet long by 55 feet wide by 23 feet high, constructed under the Embarcadero roadway. The box structure houses three simple Y crossovers and three storage tracks that provide an improved turnback and storage facility to service the entire MUNI Metro subway and streetcar system. At the south end of the box structure, a retaining-wall structure 386 feet long and a surface track section 154 feet long bring the system to the surface, to connect with a future Metro extension. (See Exhibit 1.)
Before the MUNI Metro Turnback (shown here under construction) was completed, traffic and public transportation along San Francisco's historic waterfront had become severely congested.
Construction under Market Street and the Embarcadero (downtown San Francisco's busiest streets) was challenging, with possible disruption to traffic, business, annual events and tourism. Specific construction risks and challenges included:
■ The proximity of the MMT tunneling to BART tunnels, in loose fill and soft Bay mud. These tunnels are the major transportation link for thousands of commuters every day. Tunneling directly above them, below the water table, in precarious soil conditions, required extraordinary monitoring and safety measures.
■ Wooden pilings that had supported wharves and piers in the project area had been buried when the area was landfilled. Excessive force in cutting the pilings would have damaged the BART tunnels.
■ The proximity of excavation work to a row of high-value buildings along the Embarcadero roadway. At its nearest point, excavation was only 35 feet from a National Register of Historic Places building constructed in 1889.
■ The proximity of the project to San Francisco Bay. Because of the high water table along the project alignment and potential for intrusion of groundwater at the tunnel face, the tunneling work was done under compressed air.
Exhibit 1. A major construction project under downtown San Francisco's busiest streets, through unstable, soggy landfill dotted with archeological artifacts, and within 4.5 feet of exisiting subway tunnels was carried out under budget and with only two months' slippage in an 11-year schedule.
■ Seismic activity. Just at the end of conceptual design, the 1989 Loma Prieta earthquake (7.1 magnitude) shook the area, elevating the seismic safety requirements.
Bechtel Corporation for San Francisco Public Transportation Commission (SFPTC) performed the MUNI Metro Turnback Project, with Tutor-Saliba-Perini JV the general contractor. The project team was comprised of the client, engineering manager, construction manager, subconsultants, general contractor and subcontractors and a special board of consultants.
Through a series of stringent controls, innovative procedures, and integrated management, the project was completed without disturbance to BART or damage to adjacent structures. Moreover, despite design changes that were initially expected to create a five-month delay and cost overruns, the 11-year MMT Project was completed within two months of the original schedule, and $22 million under budget.
Scope Management
The MMT Project had several key objectives, including providing underground train turnback and storage facilities east of the Embarcadero Station for a 20 percent increase in rush hour ridership by year 2007. Train capacity in the existing MUNI Metro subway was planned to increase from 20 to 30 trains per hour, while the time between trains was planned to decrease from three to two minutes, or one minute with automatic train control. The project also provides a surface extension of MUNI Metro to the CalTrain depot at Fourth and Townsend, and to Mission Bay. A Metro station at the CalTrain depot will provide connecting service to BART and thus provide a new regional rail link.
The Work Breakdown Structure subdivided the total project into manageable units of work for effective planning and control. As the fundamental linkage between cost and schedule information, the WBS facilitated efficient migration of data among cost estimates, cost control budgets, project cost forecasts, project schedules, and the corresponding management reports developed from these data. The WBS, along with the Cost Code of Accounts (a breakdown of cost data into commodity and bid item categories), formed the Project Code of Accounts. Standardization of the use of the account codes provided the construction manager (CM) with a logical and uniform structure for schedule and cost data for reporting and monitoring.
Management Plan and Control Systems. The Management Plan and Control Systems identified the control functions, the associated tools, and the deliverables. These systems were designed to support completion of the project construction within the contract budget and schedule by providing a quantified basis for timely monitoring of actual progress and performance; early warning and claim avoidance of potential impact trends in scope, cost, and schedules; analysis to anticipate problem areas; and input for corrective actions.
Engineering Management. The engineering manager integrated the activities of a team formed by Bechtel and 15 local subconsultant firms to complete a design that met both the operational requirements of the MUNI system and industrial codes and standards and that was professional, cost-effective, and in conformance with established quality standards.
Construction Management. Personnel from Bechtel and 10 other subconsultant firms in the San Francisco area formed the construction management team. The CM maintained daily contact with the City and the general contractor to plan work, coordinate interface, resolve conflicts, and negotiate changes and claims, as well as to assure the quality of construction and to explore innovative ideas for reducing cost.
Bechtel established a project management and controls program to provide a disciplined framework. The program provided cost and schedule control tools and entailed timely reporting of status, trends, and critical items. The intent was to ensure that all project control needs were identified and to provide the means to monitor and report data necessary for the project team to make informed decisions.
Budget and Scope Control. To control the total contract costs, a control budget was established with quantities, costs, and job-hour allocations based on the project code of accounts. The control budget was the original budget (contractor's awarded bid amount) and any approved scope changes. Budgeted items were allocated over time (monthly basis) to allow tracking of planned contract expenditure rates. Expenditure rates were estimated until the contractor's resource-loaded schedule was approved.
Records of scope changes throughout the contract period were maintained in a scope change log. The identification of scope changes was tracked by a trend program, then entered in the scope change log. As these trends were resolved the log was updated to reflect either scope change approval or disapproval by the City.
The trending program also provided the cost data necessary for project forecasting, provided management with early warning of any potential cost/schedule impacts, and assisted in mitigating claims. Trends that had been reviewed and resolved for inclusion into the project forecast were included in the Estimate-at-Completion cost projection.
Monthly progress reporting included a cost summary by facility, a summary of proposed contract changes, and a summary of contractor claims. All variances between forecast and committed costs were explained and all approved change orders summarized.
Project Schedule Control. The goal of this system was to provide an efficient means of accomplishing the design and construction on or ahead of schedule. Because the funding process largely dictated the design phase schedule, the Project of the Year application focused on construction schedule controls.
During construction, schedule control was maintained through a hierarchy of tools that placed specific management emphasis with the construction management team and contractor personnel. Construction-detailed work plans and schedules provided day-to-day working-level schedules that included critical information on workforce, installed quantities, construction plant, and equipment. Overall schedule progress and performance was measured and analyzed against the contractor's work plans. The contract established contractor schedule update requirements for weekly and monthly meetings. The CM or designated representative chaired the meetings and prepared the agenda. The tools used are discussed under Time/Schedule Management.
Quality Control. Bechtel established a quality program, discussed in more detail under Quality Management, that encompassed both quality assurance and quality control, and which covered the entire project from design phase through construction.
Time/Schedule Management
Conceptual design began in 1985 and completed in 1989. This phase produced train operation studies, an environmental impact statement, geotechnical investigation reports, and the conceptual design report. The final design phase, 1990–1992, included a construction contract package. This was followed by prequalification of construction contractors, bid evaluation, and selection of the general contractor.
The project had been designed to code, but after final design, the Fire Department mandated more stringent requirements. After start of construction, 17 new design tasks were released, most stemming from the San Francisco Fire Department. Changes were executed concurrent with construction and integrated into the contract.
Although completion of the three-year construction phase was delayed by two months, this was an achievement because the design changes alone were initially expected to create a five-month delay. With the coordination and full cooperation of the City, engineering, construction management, and the contractor, the funding authorization and design schedule were integrated with the construction and procurement schedule and the potential delay was reduced by three months.
In December 1994, one of the most interesting schedule challenges surfaced when the tunnel excavation crew encountered the bow of a 19th century sunken ship. To develop a strategy for continuing tunnel excavation and resolving archaeological issues, the project management, engineering, and construction management team worked closely with the contractor. The excavated materials were examined, sorted, and screened as required by the field archaeologist.
Tools used for schedule control included:
Contractual Milestone Summary Schedule (CMSS). The CMSS was established by the contract and was the plan for the total construction scope. All subsequent lower-level schedules and plans were dictated by the overall schedule parameters established in the CMSS. Presented in a bar chart time-phased format, this schedule was issued monthly, and showed current status relative to the approved plan. Every month, analysis was made of the critical and near-critical paths, the basis for activity durations on the critical path, an indication of the level of confidence in overall project duration, the identification of areas of high risk, and opportunities for schedule improvements.
Construction Schedule. The construction schedule was used as the definitive scheduling and planning tool for coordination with the general contractor. It was a critical path (schedule using Primavera Project Planner, which tracked construction and related project activities, including lead times for fabrication and procurement.
Three-Week Rolling Construction Schedule. This schedule showed all activities completed in the week past, those scheduled on a daily basis for the current week, and those scheduled for the upcoming week. This rolling three-week schedule was based on the overall construction plan depicted in the construction schedule, and was used to monitor in detail the progress against the baseline construction schedule.
Project Cost/Resource Management
The initial budget for the MUNI Metro Turnback Project was $202.3 million. The construction cost component went through several changes. The changes, primarily additional requirements by the San Francisco Fire Department, increased the cost by $10,201,000. Altogether, the changes could have resulted in a five-months-or-more delay, which could have added significantly to the costs, through teamwork and integration of efforts, delay was held to two months, and final construction cost of the project was held to $106,654,000.
Cost Management. The conceptual study of the MMT Project started in 1985, continued through the conceptual design, and the final design was completed in October 1992. Various train turnback schemes and construction methods were evaluated in the early stage of the project. Cost estimates were developed for each scheme and concept, then evaluated to select the lowest-cost option that also satisfied other conditions such as environmental constraints. The final MMT configuration was a product of this process.
As design and construction progressed, a rigorous trend program was maintained. This program identified any potential cost impact due to new changes, ideas, directions, or requirements. Project management used this tool to make logical cost/benefit decisions, which kept the cost under control.
The control and containment of costs was directly related to the early participation of project personnel in the identification, analysis and mitigation of potential cost impact items. Bechtel's cost control program included building a “cost control” mental attitude and approach within the management team; early identification of potential construction cost impacts; exploring design alternatives and initiating value engineering to identify potential cost; and close monitoring and rigorous adherence to the project management cost control philosophy.
A monthly contract cash flow schedule reflected the expenditures by month, based on the resource-loaded CPM schedule. An analysis compared the contractor invoice (incurred costs) earnings with the expenditure schedule and any noted deviations were reported to the CM for review and action.
Quality Management
Quality management was a team effort, employing a system of checks and balances in a disciplined progression, to ensure the implementation of design and construction according to established criteria, within constraints of project requirements, environmental sensitivities, agency criteria, and professional and regulatory standards.
First, the prescriptive detailed design was specified in the contract. Then, prior to bidding the MMT Project, it was decided that, to achieve the project's overall quality-control goal, the construction contract would clearly delineate separate Quality Control and Quality Assurance responsibilities for the contractor and for construction management.
Bechtel established a quality assurance program to ensure that the design met the City's objectives. Design calculations, drawings, specifications, and the study report went through a rigorous review process that included internal checking and coordination, off-project independent review, review by a special consultants board, and review by the City's organization.
The project management maintained a master control log of design drawings, specifications, general contractor's submittals and other documents on computer to ensure that only the latest issue was used in design and construction. The construction issues of drawings were reviewed, signed and stamped by a registered professional engineer. After completion of each design and construction phase, all project documents were sequentially archived so they could be retrieved easily and quickly.
Bechtel inspectors worked with the contractor in the field, discussing need for corrections as the work proceeded. Bechtel construction management conducted between four and eight quality surveillance reviews per month, approximately 180 in all. The success of the total effort and excellence of Quality Control was evident in the numbers. Despite the three-year time span, the design changes, pilings, sunken ship and resulting archeological complications, the team efforts resulted in issuance of less than 30 Contractor's Nonconformance Reports and Corrective Action Reports.
Human Resource Management
During both the design and construction phases of this project, Bechtel was fortunate to enlist the services of a number of outside firms and individuals that had worked extensively in the City of San Francisco. Their collective experience, familiarity with the history and specific technical challenges of the site, with the local community concerns, and with the political climate proved invaluable.
City, state and federal ordinances providing for nondiscriminatory employment and contracting practices were incorporated into both the design and construction contracts. Bechtel also implemented an apprenticeship-training program during both the design and construction phases. Most apprentices were young minorities or new immigrants, and each was part of the team for one year. After completion of the program, each trainee was able to secure a position in the engineering field.
By its very nature, the MMT Project depended on implementation of an integrated team approach, where Bechtel personnel worked on a continuing basis with staff members from various subconsultants as well as a number of individuals from the City of San Francisco's engineering staff.
The design and construction of the MMT Project was administered by the MUNI Capital Projects division of the City of San Francisco, but operation of the facility would be the responsibility of MUNI Operations division. Rather than waiting until the end of the project to involve the operations group in the day-to-day construction details, key members of MUNI Operations were kept advised as work progressed. Other City agencies such as the Department of Parking and Traffic, Department of Public Works, and the San Francisco Fire Department were involved in the project's day-to-day operations as design concerns and/or construction issues pertinent to their responsibilities were encountered. These working relationships were instrumental in ensuring the success of the project.
To further augment the project's integrated team, a board of special consultants was created to assist in and review key aspects of the design of the project on an as-needed basis. With the many technical challenges inherent in constructing a driven-tunnel/cut-and-cover facility in a busy and constricted urban waterfront location, the board members' combined experience and expertise was instrumental in the successful completion of the project.
Communication Management
During the construction of the MMT Project, daily personal contacts between the construction manager, engineering manager, contractor, and the City's project manager played an important role in identifying potential issues, developing strategies and plans and resolution of problems. The high level of personal communication among the team members made it possible to maintain the overall budget and schedule of the project, which underwent many changes from the original scope.
Interagency Coordination and Community Relations. The SFPTC project manager and project engineer and their staff were responsible for coordination with BART, MUNI, the Department of Parking and Traffic, the Department of Public Works, San Francisco Fire Department, and utility companies. SFPTC engineers were in constant contact with these agencies to coordinate restricted working hours, traffic routing, fire and domestic water, sewer, electric power and other utilities. Representatives of each organization were invited to the weekly project meetings, pre-activity meetings and special coordination meetings with the contractor.
Closing the Embarcadero, the City's only waterfront roadway, was a major concern, as was minimizing noise disruption to the adjoining commercial businesses. Other challenges were more political, such as how to coordinate with various parties so that the annual Bay-to-Breakers race could still start at the waterfront.
A number of tools were used to keep local businesses and property owners informed about the project. Periodic fact sheets were prepared, informing property owners and businesses of major activities that would affect their lives. Biweekly construction updates were provided in the immediate vicinity, describing what to expect on the construction site over the upcoming weeks (nighttime work, pile driving). A point of contact was established for property owners so they could receive hands-on attention and answers to their questions. Cooperative agreements were also executed with building owners along Steuart Street, which laid out specific roles and responsibilities in the event of any problems due to construction.
Immediately after the Notice-To-Proceed was issued to the contractor, a formal early action letter was sent from the CM to the contractor. The early action letter addressed the requirements, the time frame, and specific forms for implementation for each article of the general provisions, special provisions, and general requirements of the construction contract. It gave specific instructions for communication and correspondence with the CM.
Team-Building and Partnering Program. The City incorporated into the contract a partnering program to improve communications and establish mutually beneficial, achievable project goals and objectives. The program established the working relationship between the key entities and the procedures for equitable and timely resolution of issues and disputes. The project manager, construction manager, and contractor held quarterly follow-up meetings to monitor progress and identify actions for continuing the partnering program. Partnering proved to be very helpful in maintaining the schedule, and resolving disputes during MMT project execution.
In addition, a variety of recognition events and special celebrations were held, which included informal project recognition ceremonies and celebrations of major milestones, such as a groundbreaking ceremony, tunnel breakthrough ceremony, and project opening ceremony.
Risk Management
MMT project management employed innovative planning, design, and construction strategies to minimize construction risks and reduce costs.
A special consultants board of five world-renowned experts in tunneling, grouting, geotechnical instrumentation, seismic design, and slurry wall and cut-and-cover construction was impaneled in the conceptual design phase and used through the completion of construction. The consultants provided special guidance in the design, review of design details, and resolution of questions during construction.
The MMT tunnels were excavated directly above the existing BART tunnels under Market Street through a mixed face of fill and Bay mud and buried timber pilings, some of which bear upon the BART tunnel linings. The MMT tunnels were manually excavated through an open-face shield under compressed air and the timber encountered was manually cut by hydraulic chainsaws to minimize the disturbance to the ground and potential damage to BART tunnels. Contingency plans and alternative tunneling methods were prescribed in the contract documents and implemented to deal with adverse conditions and to control excessive deformation of the BART tunnels. Electronic tilt meters were installed in the BART tunnels to monitor the tunnel behavior. Construction was completed without disturbance to BART.
The MMT cut-and-cover excavation was conducted within 35 feet of a row of adjacent buildings. Several measures were implemented in order to complete the project without damage to the structures. For example, geomechanical instrumentation including settlement points, tilt gages, vibration monitors and crack gages were installed in the buildings and monitored daily to ensure that the building deformations were within acceptable limits.
The 7.1-magnitude Loma Prieta earthquake struck the San Francisco area in 1989, just at the end of conceptual design. As a result, Em-barcadaro Freeway (which would have required support during construction) was dismantled, simplifying construction. However, seismic requirements were increased, adding to the project. Rather than designing the MMT permanent facilities to withstand collapse in a magnitude 8.3 earthquake on the San Andreas Fault, it was also required that any damage from this maximum credible earthquake would be minor and readily repairable—the most stringent criteria for a transit project.
The Designer as Construction Manager. The SFPTC project manager evaluated various options for the construction management of the project and selected the designer (Bechtel) as construction manager, gaining the benefits of continuity of knowledge and experience on the unique requirements of the MMT; detailed knowledge of the construction of the BART facilities affected by MMT construction (Bechtel was project manager on BART); the ability to effectively integrate engineering support services with construction management services and provide single-point responsibility for project implementation; and intimate knowledge of the project that would reduce costs in the construction management contract.
Contract/Procurement Management
The City's public contracting code stipulates that contract awards be made to the “lowest responsible bidder.” Due to the high risk of damage to BART and adjacent buildings in construction of the MMT Project, the City decided to prequalify prospective contractors so that only qualified contractors were invited to submit price bids on the construction contract. Four key qualification criteria were developed: technical experience and capabilities, organization and personnel requirements, financial condition and capacity, safety experience and rating. Seven firms, prequalified by a panel of experts, submitted bids. The construction contract was awarded to low-bidder Tutor-Saliba-Perini JV.
The MMT Project anticipated certain changes to the work, and the bid documents contained provisions allowing for several different categories of changes. Project management required early identification of potential changes, wherever generated, and timely cost-schedule impact assessments. The MMT Project Procedures anticipated that changes would occur and detailed how changes were to be identified, monitored and processed, and how disputes over changes and pricing of changes were to be administered. The City, engineering manager, construction manager, contractor including subcontractors, and others (utilities, agencies) initiated proposed changes.
Upon execution of each Contract Change Order by all parties, the CM prepared a final change order package. It included the executed change order form, estimates, records-of-negotiation, correspondence, and a detailed indexing of all pertinent documentation relative to the scope-development and pricing of the change. This was submitted to the City for signature and issued to the contractor. A total of 144 change orders were negotiated and issued for $18,188,769.
Claims. Periodic meetings were scheduled by the CM at which all pending changes and outstanding claims were discussed with representatives of the City, CM, and contractor. Action items were identified and meeting minutes issued. Six claims were settled by the CM and contractor for $715,000. Five could not be settled at the field level and were duly referred to the Disputes Review Board, which was modeled after the ASCE standard specification. The DRB met quarterly to review construction progress and to hear disputes.
A key feature of the DRB experience on this project was that most DRB decisions were, in effect, a suggestion that the parties continue to negotiate to seek an equitable settlement rather than a “he's right/you're wrong” ruling. As the contract did not specify any particular procedure for handling claims that could not be resolved directly by the DRB, the City, contractor, and Bechtel CM handled each of the approximately half-dozen such claim issues on an ad hoc basis. As a result, all of the claim disputes brought before the Board have to date been settled without resort to litigation.
AT THE OPENING CEREMONIES for the project in December 1996, San Francisco Mayor Willie Brown displayed the client's satisfaction with the project by proclaiming it a contributor to “one of the safest and most efficient systems of public transportation … in the world.” ■
Ching L. Wu served as engineering project manager for the MMT. Gail Harwell is a communications consultant with BCIV Marketing and Communications.
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