California High-Speed Rail
The California High-Speed Rail Authority is building a rail link from Los Angeles to San Francisco that will allow passengers to complete the journey in just 2 hours and 40 minutes. Work is underway in the Central Valley.
Tunnels will be required in the north across the California Coast Range between Gilroy and Merced; and in the south in the Tehachapi Mountains between Bakersfield and Palmdale, and the San Gabriel Mountains between Palmdale and Burbank.
The alignments currently under consideration involve between 45 to 50 miles of tunnels that range in length from several thousand feet to over 20 miles, some of which are over 2,000 ft underground. The target revenue service date for the Los Angeles to San Francisco segment is 2029, according to the authority’s Draft 2018 Business Plan.
As part of the effort to advance the Silicon Valley to Central Valley Line of the program, the California High-Speed Rail Authority (Authority), along with its geotechnical consultants Kleinfelder Inc. and Fugro Consultants, have conducted geotechnical explorations in the City of San Jose and Santa Clara County.
WSP is serving as the authority’s Rail Delivery Partner (RDP).
Clearwater Program Effluent Outfall Tunnel
The Clearwater Program’s Joint Water Pollution Control Plant (JWPCP) Effluent Outfall Tunnel Project is part of an extensive effort by the Sanitation Districts of Los Angeles County to analyze the needs of its Joint Outfall System to the year 2050. The Effluent Outfall Tunnel is envisioned to enhance the existing 8- and 12-ft tunnels with a new 37,000-lf, 18-ft ID post-tensioned concrete segmented lined tunnel. All tunneling work will be done from a single shaft located at the Districts’ JWPCP located in the City of Carson. Structures located at the start and end of the tunnel will connect to the existing Ocean Outfall System facilities. Bids are due Sept. 18, 2018, with award scheduled for Oct. 24, 2018. Construction is anticipated to start Q1 2019.
Mountain Tunnel Improvements
This project for the San Francisco Public Utilities Commission (SFPUC) involves 12 miles of rehabilitation of the 10-ft diameter, concrete-lined, horseshoe tunnel. Work includes concrete lining repairs, contact grouting, downstream valve control structure, large control valve installations, new tunnel adit, adit/portal improvements, tunnel siphon extension, water cut-off grouting, water discharge treatment, access roadway improvements, temporary staging area excavations and grading, and environmental mitigations. Most of the work will be 1,000 ft below ground surface and will be accessed via the downstream Priest Portal, and Adits 5/6 and 8/9 at intermediate locations along the alignment. Access will also be available 7 miles upstream via the 13.5-ft diameter unlined section of the tunnel from Early Intake. The project designer is McMillen Jacobs Associates (MJA) with AECOM as environmental consultant. Project design and environmental review has commenced, and both phases are anticipated to be completed at the end of 2019. Construction is scheduled for 2020 through 2026.
The Interlake Tunnel for the Monterey County Water Resources Agency comprises an 11,000-ft long, 10-ft diameter, gravity-flow tunnel and related structures that would divert water from Lake Nacimiento (Nacimiemto Reservoir) to Lake San Antonio (San Antonio Reservoir). The benefits of the project include increased surface water supply and reduced flooding downstream of Lake Nacimiento by diverting water into Lake San Antonio that would otherwise flow out to the ocean. The project also includes a spillway modification at Lake San Antonio to add an additional 45,000 acre-feet of water storage. The engineering firm EPC Consultants has been hired by the agency as Program Manager for the project. McMillen Jacobs Associates and GEI Inc. have been retained for preliminary engineering and design services for the projects. Design was 30 percent complete as of June 2018. Design-build SOQ is scheduled for Q4 2018. Construction is scheduled to begin in Q4 2019. The estimated project cost is approximately $80 million.
California Water Fix
The California Water Fix Program is a comprehensive effort to improve water conveyance in the Sacramento-San Joaquin Delta region. Key components of the program include a series of water conveyance tunnels that will allow for transport of up to 9,000 cfs of water directly from the Sacramento River to the major export pumping plants in the south end of the Delta. The components of this program will replace the current water diversion activities that rely on a series of improved channels and canals to move the water southward in the Delta. The program consists of three river intake structures, approximately 10 miles of 29-ft and 40-ft ID tunnels, and approximately 60 miles of 40-ft ID main conveyance tunnels, and a 9,000 cfs pumping facility located at the terminus of the main tunnels. The main conveyance tunnels will be configured in a parallel twin bore arrangement, with tunnel invert depth of averaging approximately 150 ft below ground surface. In addition to launching and receiving shafts, a series of ventilation/access shafts will be constructed along each tunnel reach. Current conceptual engineering efforts have been completed. Tunnel design is anticipated to commence in mid-2019 with the first tunnel contracts being advertised for construction bids in mid/late-2020. Subsequent tunnel construction packages will be advertised on approximate 6-month intervals following the first contract award. Approximately five to six tunnel construction contracts will be awarded under this program. It is currently anticipated the facilities will be operational by 2033.
BART Silicon Valley Extension
On June 4 the Federal Transit Administration issued a Record of Decision for the $4.7 billion, 6-mile BART Silicon Valley Phase II Extension into downtown San Jose. Five miles of the extension are planned to be underground, constructed by a single, large-bore TBM on the order of 45-ft in diameter. The extension includes four stations (three underground). The overall project is a 16-mile extension of the Bay Area Rapid Transit system in the San Francisco Bay area. Cost estimates are in the range of $5 billion. Project construction is planned to start by 2021 with passenger service by 2026. A joint venture of HNTB and WSP agreed to a four-year, $88.3 million program management contract with the owner, Santa Clara Valley Transportation Authority (VTA).
DISTRICT OF COLUMBIA
Potomac River Tunnel Project
The Potomac River Tunnel is a component of DC Water’s long-term control plan (LTCP), also known as the DC Clean Rivers Project. The Consent Decree establishes schedules for construction of the Potomac River Tunnel and other CSO control facilities under the DC Clean Rivers Project, including a 2025 deadline to implement the project in its entirety. The Potomac River Tunnel will be located approximately 100 ft below ground. CSOs captured by the Potomac River Tunnel would be conveyed to the Blue Plains Advanced Wastewater Treatment Plant.
Northeast Corridor Superconducting Maglev
The Environmental Impact Statement for the first leg of the Northeast Corridor Superconducting Maglev project is underway with the Record of Decision anticipated in 2019. Construction is planned for 2020. The first leg comprises 60 km from Washington to Baltimore, 75 percent of the alignment in tunnel, and three underground stations (Washington, Baltimore and BWI Airport). The total cost is over $10 billion. TBM tunneling is anticipated as a single bore with guideways (outside tunnel diameter approximately 15m). Five or six TBMs are anticipated. Owner: TNEM/BWRR; Prime Consultant: Louis Berger; Tunneling subconsultant: Gall Zeidler.
Project Clear Tunnels
Metropolitan St. Louis Sewer District (MSD) has begun an ambitious program called Project Clear, a multi-billion dollar investment addressing wastewater overflows. The system improvements include construction of nine tunnels to control sewer overflows.
Upcoming tunneling components of Project Clear include (Project, Construction Begin, Construction Cost Estimate, Tunnel Length, Tunnel Diameter):
- Lower & Middle Des Peres Storage Tunnel, 2020, $631,000,000, 9 miles, 30 ft dia
- University City Sanitary Storage Facility, 2018, $40,000,000, 1,250 ft, 30 ft dia
- Lower Meramec Tunnel, 2018, $170,000,000, 6.8 miles, 8 ft dia
- River Des Peres Tributaries CSO Tunnel, 2024, $375,000,000, 12,144 ft, 20 ft dia
- Upper River Des Peres CSO Storage Tunnel, 2028, $226,000,000, 8,976 ft, 24 ft dia
Flushing Bay CSO
The New York City Department of Environmental Protection has begun drafting an RFP for design of 2.5-mile long, 25 million gallon CSO tunnel in Queens as part of a Long-Term Control Plan. The tunnel is expected to be 18-20 ft in diameter an estimated cost of between $670 million $829 million for the preferred alternative. Preliminary plans envision construction occurring from 2026 to 2035. DEP expects to initiate design in 2019.
Hudson Tunnel Project/Gateway
The Hudson Tunnel Project is a new two-track heavy rail tunnel along the Northeast Corridor from the Bergen Palisades in New Jersey to Manhattan that will directly serve Penn Station New York. It consists of three major elements: the Hudson Yards right-of-way preservation project, the Hudson Tunnel, and the rehabilitation and modernization of the existing North River tunnel.
A joint venture of WSP, AECOM and STV has been awarded the design contract. The tunnel portion of the contract, estimated at $12 billion to $13 billion, is envisioned to be a design-build contract including the Palisades Tunnel and Hudson Tunnel. Construction was expected to begin in 2019 but uncertainties regarding funding may impact the schedule. The project was expected to receive a Final Environment Impact Statement in March 2018.
The Hudson Tunnel Project is part of the Northeast Corridor Gateway Program, a series of strategic rail infrastructure investments designed to improve current service and create new capacity. The Port Authority of New York and New Jersey (PANYNJ) currently serves as the project sponsor, but the project is a joint undertaking that also includes Amtrak and New Jersey Transit (NJ TRANSIT).
The existing North River Tunnel, opened in 1910, is owned by Amtrak. NJ TRANSIT and Amtrak operate approximately 450 trains each weekday through the tunnel that carry over 200,000 daily passenger trips. The North River Tunnel presents reliability challenges due to damage from Superstorm Sandy in 2012, as well as the overall age the tunnel and the intensity of its current use. Significant delays to a large number of trains occur when problems arise.
The benefits of the Hudson Tunnel Project are twofold. First, the new tunnel will enable the closure of the existing tunnel for reconstruction without causing a significant reduction of capacity. Second, once renovations on the North River Tunnel are complete, its reopening will provide greater operational flexibility and system redundancy in the event of malfunction.
Preparation of an Environmental Impact Statement is currently underway, and was expected to be completed in March 2018. The selection of a locally preferred alternative and its incorporation into the region’s fiscally constrained long-range plan was expected to occur in the first quarter of 2018. The original schedule projected both the new tunnel and the rehabilitated tunnel open for revenue service by 2028.
Second Avenue Subway – Phase 2
Design is underway for the Phase 2 of the second Avenue Subway. A joint venture of WSP and STV is working on the design for the project that extends the line northward from 96th Street to 125th Street – a total of 1.5 miles with three new stations. The alignment will use some existing tunnels originally built in the 1970s, in addition to new soft-ground TBM tunnels. The cost estimate for this phase of the project is $6 billion, with revenue service anticipated between 2027 and 2029.
NEORSD Project Clean Lake
Project Clean Lake for the Northeast Ohio Regional Sewer District (NEORSD) includes several major tunnel components to store and convey combined sewer overflows. The projects include:
- Westerly Storage Tunnel – 9,600 ft of 25-ft diameter tunnel. The design contract was awarded to a joint venture Mott MacDonald and MWH in fall 2015 and also includes a $28 million 46-ft diameter, 200-ft deep submersible Tunnel Dewatering Pump Station. The Westerly Storage Tunnel advertised for bid in Q4 2017, and in March was awarded to Jay Dee-Obayashi for $135 million. The Westerly Tunnel Dewatering Pump Station will bid in 2019;
- Shoreline Storage Tunnel – 15,300 lf of 21-ft diameter soft ground CSO tunnel. It is anticipated to bid in 2021;
- Shoreline Consolidation Sewer – 11,700 lf of 9.5-ft diameter soft ground tunnel. It is anticipated to bid in 2021;
- Southerly Storage Tunnel – 18,340 lf of 23-ft diameter CSO tunnel. It is anticipated to bid in 2024;
Big Creek Storage Tunnel – 22,400 lf of 18-ft diameter CSO tunnel. It is anticipated to bid in 2029.
ALCOSAN CSO Tunnels
The Allegheny County Sanitary Authority (ALCOSAN) is designing a tunnel program to control combined sewer overflows (CSOs) as part of a consent decree with EPA. The $2.8 billion system improvement program is expected to include tunnel segments to store and treat overflows. The improvements are slated to be complete by 2026. The tunnels include: Ohio River Segment (1.9 miles, 12-14 ft in diameter, $84 million); Allegheny River Segment (3.6 miles, 12-14 ft in diameter, $136 million); and Monongahela River Segment (4.5 miles, 12-14 ft in diameter, $152 million). Additionally, the program will include interceptor and consolidation sewers, dewatering pump station and treatment plant improvements. To date, a formal agreement has not been reached, so plans are not finalized.
The Narragansett Bay Commission (NBC) has begun conceptual design of the third and final phase of its Combined Sewer Overflow Program. Phase III includes the Pawtucket Tunnel, NBC’s second CSO storage tunnel. NBC completed the Providence Tunnel, a 16,500-ft long, 26-ft diameter CSO storage tunnel, in 2008 during Phase I of its CSO program.
The Pawtucket Tunnel will be approximately 13,000 ft long, 28 ft in diameter and located in bedrock about 200 ft below the ground surface. The contract to construct the Pawtucket Tunnel will include the launch and recovery shafts (which will become permanent access shafts), two to three drop shafts with connecting adits at existing outfall locations, and an underground shaft- or cavern-style tunnel pump station.
Mechanical fit out of the tunnel pump station will be performed under a separate contract. Construction of diversion structures, gate and screening structures and consolidation conduits at existing outfall locations will be performed under separate contracts as well.
The launch shaft and tunnel pump station will be located at NBC’s Bucklin Point Wastewater Treatment Facility in East Providence, Rhode Island. The alignment will be parallel to the Seekonk River and Blackstone River, and end near the border of Pawtucket and Central Falls, Rhode Island. An 8,800-ft long, 10-ft diameter conveyance tunnel, which will connect to the Pawtucket Tunnel, is planned to begin after the Pawtucket Tunnel is completed. The program/construction manager for Phase III is Stantec and its teaming partner Pare Corporation. Construction of the Pawtucket Tunnel is anticipated to begin in late 2020 or early 2021.
Phase 2 Lake Travis Deep Water Intake
The Brushy Creek Regional Utility Authority (BCRUA) has embarked on a multiple year program to increase capacity and manage concerns associated with recent historic low water levels of Lake Travis. The program includes: a multiple level-screen deep water intake assembly and shaft extending about 70-ft below lake bottom; approximately 10,000-ft of 96-in. diameter tunnel to convey water by gravity from the intake to a new on-shore pump station (with a subterranean forebay, multiple individual pump wells and a 30 ft diameter wetwell extending about 300 ft below grade); and 3,000-ft of 84-in. diameter pressurized transmission tunnel. Final design is anticipated to begin in 2019, and construction is anticipated to begin in 2021 or 2022. BCRUA is currently acquiring easements for the project.
Hampton Roads Bridge-Tunnel
The HRBT Expansion project will build another bridge-tunnel and widen the four-lane segments of I-64 in Hampton and Norfolk to ease daily congestion between the Peninsula and South Hampton Roads, a corridor vital to Virginia’s economy. The project owner, VDOT, announced that both short listed teams have opted to use the bored tunnel method as the basis for their proposals, which will be submitted in late 2018. The project cost is estimated between $3.3 and $3.8 billion, with contract award expected in early 2019.
Ship Canal Water Quality Project
Seattle Public Utilities is planning to build a tunnel jointly with King County to reduce the amount of combined sewer overflows into local waterways. Construction is expected to start the first half of 2019. The project includes a 2.7-mile long storage tunnel with a diameter of 18 ft, 10 in. excavated by PEB TBM 30 to 90 ft below grade. Estimated cost for the storage tunnel is $175 million to $225 million. The design-bid-build construction contract is scheduled to advertise in Q2 2019 with completion by Q4 2022.