BOARD AGENDA MEMORANDUM
SUBJECT:
Title
Update on the Anderson Dam Seismic Retrofit Project; and Amendment No. 6 to Agreement No. A3676A with URS Corporation, for Design Services for a Not-To-Exceed Fee of $6,001,293, Resulting in a Total Not-To-Exceed Fee of $23,387,219, for the Anderson Dam Seismic Retrofit Project, Project No. 91864005 (Morgan Hill) (District 1).
End
RECOMMENDATION:
Recommendation
A. Receive an update on the Anderson Dam Seismic Retrofit Project; and
B. Approve Amendment No. 6 to Agreement No. A3676A with URS Corporation for design services for the Anderson Dam Seismic Retrofit Project, for a not-to-exceed fee of $6,001,293, resulting in a total not-to-exceed fee of $23,387,219 and extend the Agreement term.
Body
SUMMARY:
The purpose of this agenda item is to present an update on the Anderson Dam Seismic Retrofit Project (Project) construction schedule as compared to the other dam retrofit construction schedules; to present an update on the Project’s environmental documentation and permitting strategy; and to recommend Board approval of an amendment to the design services agreement with URS Corporation (Consultant) to incorporate scope changes and level of effort required to complete the Project design.
Project Background
In 2011, the District completed a seismic study of Anderson Dam, which indicated that material at the base and foundation of the dam embankment would weaken due to liquefaction in a 7.25 magnitude earthquake [the maximum credible earthquake (MCE)] on the Calaveras Fault, located approximately 1.2 miles from the dam. This could significantly deform the dam embankment, risking an uncontrolled release from the Reservoir. The 2011 study also indicated that an MCE could trigger fault offset on the Coyote Creek-Range Front fault zone located in the vicinity of the dam, which would damage the existing outlet pipe, precluding safe drawdown of the reservoir.
The District initiated the Anderson Dam Seismic Retrofit Project in 2012 to address the seismic deficiencies at the dam and to meet the design requirements of the Federal Energy Regulatory Commission (FERC) and the California Department of Water Resources, Division of Safety of Dams (DSOD). The Project’s planning phase was initiated in 2012 and completed in July 2013. The design phase was initiated in August 2013. As Project design work proceeded, an administrative draft of an Environmental Impact Report (EIR) was prepared in 2014, as required by the California Environmental Quality Act (CEQA) for the Project.
Between 2014 and 2016, detailed geotechnical and geologic investigations were performed on and around the dam embankment to further inform the seismic retrofit design. On December 10, 2016, staff presented the findings from these investigations to the Board and recommended that deconstruction and replacement of most of the existing dam would be necessary to address the dam’s deficiencies. On January 23, 2018, staff informed the Board that the Project’s 30% design documents had been completed, and included embankment reconstruction, outlet works, temporary stockpiles during construction, construction sequencing, reservoir operations during construction, and a spillway condition assessment.
The Project’s 60% design was completed in April 2018, and in July 2018, the Board of Consultants (BOC), FERC, and DSOD reviewed the 60% design and requested supplemental geotechnical investigations and analysis be performed for the spillway, in-reservoir borrow and stockpiles areas, outlet works, and embankment reconstruction design before proceeding with further design of the Project. Amendment No. 6 to the design services agreement is recommended so that such additional scope can be added.
Construction Schedules for Dam Seismic Retrofit/ Improvement Projects
The Anderson Project team is proceeding with preparing the 90% design and continuing preparation of the Project’s environmental documents and permitting efforts. If all the necessary permits are secured in a timely manner, the Anderson Dam Project construction would be initiated in spring 2020. At the present time, the Calero Dam Seismic Retrofit Project is nearing completion of the 60% design and preparation of the CEQA document is underway. It is anticipated that Calero Dam construction would begin in spring 2021. However, because both Anderson and Calero reservoirs play a key role in the District’s raw water supply system, these reservoirs cannot be dewatered at the same time without seriously impacting local water supply reliability, as explained in the sections that follow.
Loss of Anderson Reservoir Emergency Storage. Anderson Reservoir’s operating rule curve requires 20,000 acre-feet (AF) be retained as emergency storage at all times. This emergency pool is used to provide water to treatment plants in the event of an emergency in the imported water supply system. During the planned 5-year construction of the Anderson Dam Project, the reservoir storage will be unavailable for a 2-year dewatering period during which the dam embankment will be deconstructed and re-built.
The only other local source of water that can supplement water to treatment plants during emergencies is Calero Reservoir. Current seismic restrictions on Calero Reservoir limit storage to 46% of its full capacity, or about 4,585 AF. When Anderson Reservoir is dewatered, staff has determined that it would be desirable to hold at least 20% of Anderson’s 20,000 AF emergency storage (or 4,000 AF) in Calero Reservoir for emergency purposes. Under current storage restrictions, Calero Reservoir would yield only 600 AF of active storage. With this limited storage, and an outlet capacity of about 50 cubic feet per second (cfs), Calero Reservoir would offer limited relief as a backup water supply to the treatment plants or in helping to mitigate water quality issues during the two years of a dewatered Anderson Reservoir.
Water Supply Reliability Risk Reduction. The risks of a dewatered Anderson Dam to raw water reliability could be partially mitigated by completing the construction of the Calero Dam Seismic Retrofit Project before dewatering Anderson Reservoir. This would restore the 9,934 AF capacity of Calero Reservoir and increase its outlet capacity from 50 cfs to 100 cfs. If an interruption in imported water deliveries were to occur when Anderson Reservoir is dewatered, a retrofitted Calero Dam/Reservoir, together with other sources, could provide sufficient flows for several weeks to meet treated water demands.
Staff Recommendation: Initiate Calero Dam Retrofit First. Based on water supply reliability analysis, staff recommends initiating the Calero Dam retrofit in advance of starting construction at Anderson Dam. Based on a 2021 start for the Calero Dam retrofit, Anderson Dam construction would be initiated in 2022. Since the first two years of Anderson Dam construction would be dedicated to building the new outlet tunnel, Anderson Reservoir would continue to operate while Calero Reservoir would be dewatered. The dewatered period for Calero Reservoir would end in early 2023, and the reservoir would be refilled in advance of the Anderson Dam dewatering, which would occur after two years of tunnel construction (early 2024). The current and proposed construction schedules for the two dams are presented in Attachment 1.
Attachment 1 also presents current and proposed construction schedules for the Guadalupe Dam Seismic Retrofit and the Almaden Dam Improvements projects. The current anticipated construction start for Guadalupe Dam is the same as that for Calero Dam (2021). However, per the Valley Habitat Plan (VHP), reservoirs located in the same watershed cannot be dewatered simultaneously. Since Guadalupe, Almaden, and Calero reservoirs are all in the same watershed, the construction schedules for Guadalupe and Almaden dams have also been updated.
Prior to initiating construction of the dam seismic retrofit projects, an interim emergency reservoir storage policy will be prepared for Board consideration.
Table 1 presents a summary of current and proposed construction start dates for the dam seismic retrofit projects (Anderson, Calero, Guadalupe) and the Almaden Dam Improvements project.
Table 1. Dam Seismic Retrofit/Improvement Projects
Current and Proposed Construction Start Dates
|
Project |
Construction Start Date |
|
|
Current |
Proposed |
|
Anderson Dam |
2020 |
2022 |
|
Calero Dam |
2021 |
2021 |
|
Guadalupe Dam |
2021 |
2023 |
|
Almaden Dam |
2022 |
2025 |
Environmental and Permitting Strategy Update
At the Board’s April 10, 2018 meeting, staff presented the Anderson Dam Project’s environmental and permitting strategy and anticipated schedule. At the time, the planned milestones for the Project’s Environmental Impact Report (EIR) were to release the Draft EIR for public review in Fall 2018, certify the EIR in Spring 2019, then secure the necessary permits in a 12- to 18-month timeframe.
Two Project developments have occurred in the past several months that will require a modification to the above-described plan.
1. The Project team initiated informal consultations with multiple environmental resource agencies in late April 2018, and continues to host bi-monthly multi-agency meetings to present Project developments and District considerations of mitigation projects to address the Project’s impacts. In these discussions, the environmental resource agencies have suggested that the permitting process would be more streamlined if the District’s Draft EIR includes detailed descriptions of not only the Project’s impacts, but the planned mitigation that will be undertaken to address these impacts.
2. In late July 2018, FERC, DSOD, and the BOC held a meeting with the Anderson Dam Project team to review the 60% design plans that had been completed in late April 2018. The outcome of the review included a BOC recommendation for additional geotechnical borings to inform certain aspects of the embankment retrofit design, and a request from DSOD that the District further evaluate possible modifications to the unlined channel immediately downstream of the Anderson spillway chute. The results of these additional efforts may change the Project footprint and Project description which must be fully described in the Draft EIR.
Responding to the BOC and DSOD 60% design review recommendations, and incorporating a more detailed description of proposed mitigation in the Draft EIR will extend its preparation period by 6 to 8 months. The certification of the Final EIR will be extended by the same amount of time. Greater detail of the proposed schedule changes is included in Attachment 1.
Table 2 presents a summary of current and proposed EIR and permitting milestone dates for the Project.
Table 2. Anderson Dam Seismic Retrofit Project
Current and Proposed EIR & Permitting Finish Dates
|
EIR & Permitting |
Finish Date |
|
|
Current |
Proposed |
|
Release Draft EIR for public review |
Fall 2018 |
Mid-2019 |
|
Certify Final EIR |
Spring 2019 |
Early 2020 |
|
Secure Permits |
Summer 2020 |
Spring 2021 |
Coordination of Anderson Dam Retrofit and Coyote Creek Flood Protection Projects
The Anderson Dam Retrofit will require reservoir dewatering for a period of 2 years while the embankment is deconstructed and rebuilt. During the dewatering period, all of the Coyote Watershed’s storm runoff that would normally be captured by Anderson Dam will be conveyed directly to Coyote Creek. Although these flows will be somewhat controlled by staff operations, a series of major storms may result in high volumes of discharge directly to Coyote Creek. Staff for the Anderson Dam Retrofit and Coyote Creek Flood Protection Projects are coordinating on the progress of both Projects and participating in flood potential analyses. The Coyote Creek Flood Protection Project team anticipates that some flood improvements to Coyote Creek may be completed prior to the Anderson Reservoir dewatering period.
Amendment No. 6 to URS (Consultant) Design Services Agreement
An amendment (Attachment 2) to extend the term of the subject Agreement and modify the scope of services to reflect the additional work requested by the BOC, FERC, and DSOD is recommended for the design services agreement with the Consultant.
The original Agreement with the Consultant for design services for the Anderson Dam Seismic Retrofit Project was approved by the Board on August 27, 2013 for a not-to-exceed fee of $11,384,761. Amendments Nos. 1, 2, 3, and 4 were administrative in nature (extending the Agreement term and updating the Agreement’s standard terms and conditions), and were executed on December 28, 2015; August 11, 2016; February 21, 2017; and May 17, 2017, respectively. Amendment No. 5 was approved by the Board on July 25, 2017 for a not-to-exceed fee of $6,001,165, resulting in a total not-to-exceed fee of $17,385,926. Amendment No. 5 expanded the scope of work to reflect the more extensive dam retrofit as determined from three years of geotechnical and geologic investigations, and extended the Agreement term.
Since July 2017, the Consultant completed the 30% design (November 2017) and the 60% design (April 2018). In July 2018, the BOC, FERC, and DSOD met with staff to review the 60% design and requested additional geotechnical investigations and analysis to design for the spillway replacement; confirm the soil structure in the “in-reservoir” stockpile areas; and provide additional information for the planned outlet works and embankment reconstruction. Another addition to the Consultant’s scope of work is development and design of restoration of County Parks lands that have been identified for construction staging and stockpiling.
Consultant Agreement Work Performed to Date
The Project’s design services agreement includes the following Consultant tasks:
Task 1 - Project Management Services
Task 2 - Data Collection and Investigations
Task 3A - Basis of Design (Approved for Design)
Task 3B - Basis of Design (Prior Approval Required)
Task 4 - 30% Design Document Preparation
Task 5 - 60% Design Document Preparation
Task 6 - 90% Design Document Preparation
Task 7 - Final Design Document Preparation
Task 8 - Bid and Award Services
Task 9 - Supplemental Services during Design
The Consultant’s work efforts to date have resulted in the firm substantially completing of Tasks 1 through 5. Task 9, Supplemental Services during Design, has been fully utilized to fund additional necessary site investigations and the preparation of revised and additional technical memoranda to develop the modified Project to a 60% design level by April 2018. The use of Supplemental Services for Tasks 1 through 5 have been carefully scoped by staff and the Project Management Consultant (PMC) and formalized in individual task orders. Budgets for these task orders have been closely monitored and deliverables have been reviewed for timeliness and completeness.
Budgets for future Tasks 6, 7 and 8 have not been utilized to date. To complete the design phase, Amendment No. 6 will allocate additional funds to these tasks to expand the scope of work to include additional geotechnical investigations and analysis recently requested by the BOC, FERC, and DSOD and design of restoration plans for County Parks lands.
Staff Management of Consultant Agreement
Staff and the Project Management Consultant (PMC) have been actively monitoring and managing the Consultant’s performance to meet the goals and terms of the Agreement. Monthly design meetings and frequent technical discussions are held with the Consultant to assess task progress. As generally required in all District consultant agreements, consultants are required to submit detailed monthly progress / status reports with their invoices. These reports are scrutinized by the PMC and staff before approval of any payment to the consultants.
Another general requirement in the District’s consultant agreements is the consultant’s preparation and implementation of an internal Quality Assurance and Quality Control (QA/QC) Plan for all deliverables transmitted to the District. As part of the deliverable acceptance process for this Project, the PMC and staff also perform QA/QC review of all deliverables received from the Consultant. The Consultant’s deliverables are also carefully reviewed by DSOD and FERC staff.
Additional Scope of Work for Amendment No. 6
Staff recommends amending the Consultant’s design services Agreement to expand the scope of work as described earlier, and to extend the Agreement term to allow sufficient time to perform the additional services. The following additional tasks will be required and are included in Amendment No. 6:
1. Additional project management time due to the extension of the Agreement term including meetings, progress reports and workshops;
2. Geotechnical investigation and analysis to design the spillway replacement;
3. Additional geotechnical investigation and analysis for in-reservoir borrow sources, stockpiles, staging, haul roads, outlet works, remnant core strength characterization, Coyote Creek improvements, and County Land restoration;
4. Updates to geotechnical baseline reports for the modified Project; and
5. Supplemental Services to allow for unanticipated costs potentially associated with necessary reservoir rim stability analysis and design, additional geotechnical investigations and reporting, updating ground motions, additional workshops and meetings, and other baseline memoranda.
Per the existing Agreement, supplemental tasks will require authorization by the District before execution.
The current Agreement with the Consultant expires on July 31, 2020. Staff’s recommendation is to extend the term of the Agreement to June 30, 2022 to attain 100% completion of the modified Project design. A summary of scope and fee-related amendments to date is presented in Table 3.
Table 3. Summary of Board-Approved and Staff-Recommended Scope and Fee-Related Amendments to Date
|
Task |
Description |
Original Agreement NTE* Fees |
Amend. No. 5 NTE Fees |
Amend. No. 6 NTE Fees |
Revised Total NTE Fees |
|
1 |
Project Management Services |
$877,668 |
$591,973 |
$199,873 |
$1,669,514 |
|
2 |
Data Collection and Investigations |
$2,555,092 |
$747,012 |
$1,485,127 |
$4,787,231 |
|
3A |
Basis of Design (Approved for Design) |
$1,571,579 |
$405,123 |
$170,253 |
$2,146,955 |
|
3B |
Basis of Design (Prior Approved Required) |
$428,816 |
$1,552,146 |
$290,465 |
$2,271,427 |
|
4 |
30% Design Document Preparation |
$1,361,525 |
$0 |
N/A |
$1,361,525 |
|
5 |
60% Design Document Preparation |
$1,408,868 |
$1,084,022 |
N/A |
$2,492,890 |
|
6 |
90% Design Document Preparation |
$787,007 |
$403,640 |
$1,881,747 |
$3,072,394 |
|
7 |
Final Design Document Preparation |
$336,182 |
$185,436 |
$335,871 |
$857,489 |
|
8 |
Bid and Award Services |
$160,564 |
$31,813 |
$108,129 |
$300,506 |
|
9 |
Supplemental Services During Design |
$1,897,460 |
$1,000,000 |
$1,529,828 |
$4,427,288 |
|
TOTAL |
$11,384,761 |
$6,001,165 |
$6,001,293 |
$23,387,219 |
* NTE = Not-to-Exceed
** Amendment Nos. 1, 2, 3, and 4 were administrative and did not increase Agreement scope/fees.
Next Steps
The Project work to be performed in the next several months includes:
1. The Project description will be revised to reflect potential environmental mitigation and effects to species impacted due to dewatering.
2. Staff and District’s Consultants will continue development of the detailed diversion operation plan for conveyance of watershed runoff during the 2-year dewatering period.
3. Anticipated release of the Draft EIR for public review mid-2019, with certification of the Final EIR in early 2020.
4. Submittal of 90% design plans - August 2019.
5. Anticipated acquisition of necessary permits - Spring 2021.
6. Anticipated start of construction - Spring 2022.
FINANCIAL IMPACT:
Amendment No. 6 to Agreement A3676A with URS Corporation for Design Services for the Anderson Dam Seismic Retrofit Project will add a not-to-exceed fee of $6,001,293, resulting in a total not-to-exceed fee of $23,387,219. There are adequate funds in the Project’s FY 2019 Board-Approved Budget to encumber the funds necessary for the Consultant’s work effort this fiscal year. Future fiscal years’ budgets will include the remaining fees for future encumbrances.
CEQA:
The recommended action does not constitute a project under CEQA because it does not have a potential for resulting in direct or reasonably foreseeable indirect physical change in the environment.
ATTACHMENTS:
Attachment 1: PowerPoint
Attachment 2: Amendment No. 6
UNCLASSIFIED MANAGER:
Manager
Katherine Oven, 408-630-3162