SOUND TRANSIT EXPANSION AND CHALLENGES FOR SYSTEMS INTEGRATION Conrad Fawcett, Mott MacDonald and CMC Project Manager for Northgate / East Link Systems 1601, 5th Avenue, Seattle, WA, 98101 Telephone 206 370 5688 Email: conrad.fawcett@mottmac.com Ben Neeley, Principal Construction Manager, Sound Transit 401 S Jackson St, Seattle, WA, 98104 Telephone 206 903 7050 Email: ben.neeley@soundtransit.org NUMBER OF WORDS: 3002 ABSTRACT Sound Transit has started on its plan for a continuous series of system expansions to its network to five times its current size. This is to be achieved within the rapidly growing Puget Sound corridor, which includes Seattle, Bellevue, Redmond, Everett, and Tacoma. The expansion will strain construction resources, particularly in Rail Systems Engineering. Projects must be planned and executed in an integrated manner to avoid crisis efforts in the late construction and commissioning stages. In addition, Sound Transit will determine the most effective construction contract model for each project, be it Design Build, Design-Bid-Build, or GCCM (CM At risk), so the integration approach will need to be adapted to the contractual relationship. Sound Transit and its partners worked together to set up a rigorous interface identification, definition and resolution process prior to the Construction phase. The Contractor has now started the physical works which have highlighted areas in which the team has an opportunity to review and improve the established Systems Integration processes in the light of hard on-site construction experience. This presentation will provide an update on the status of Sound Transit's expansion, the status of design and construction, and some of the challenges the project teams face. We will also cover the re-evaluation of our Systems Integration processes and explain the deficiencies that led to some interface issues, and what we did to improve in readiness for the future. Finally, we will cover some of the challenges and opportunities that are presented by the differing contracting methods in relation to effective systems integration.

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Figure 1: Sound Transit light rail vehicles on Central Link, with Mount Rainier looking on

Sound Transit’s Central Link Light Rail system runs north/south through the city of Seattle, stretching about 20 miles from Angle Lake and the Seattle-Tacoma Airport in the South, through the downtown to the University of Washington in the north. The current line was constructed through a number of projects and extensions which incremented the alignment from 2003 to 2016. The current light rail system travels on a mixture of elevated and at-grade guideway south of the downtown, entering the Downtown Seattle Transit Tunnel in the downtown area, and newer twin-bore tunnels for the northern section between Capitol Hill and the University of Washington. The Light Rail Vehicles operated by Sound Transit and King County Metro are dual-articulated light rail vehicles running in sets of up to four cars, powered by an overhead contact system delivering 1500V dc.

Voters approved “ST2” funding for a package of further extensions in 2008, and Sound Transit is now well into the construction of the final phases of that package of extensions: the Northgate Link Project extends for four miles north, from the University of Washington to Northgate, and the East Link Project extends the network for 14 miles, for the first time to the east, across Lake Washington into the cities of Mercer Island, Bellevue and Redmond.

Figure 2: Northgate Link Extension

Northgate Link is mainly in twin bored tunnel, emerging through the portal just south of Northgate, which will feature an elevated station. Northgate Link has two underground stations at University District and Roosevelt. As of May 2019, the tunnels are now complete, the three stations’ structures and the trackwork are nearing completion, and installation of the Rail Systems commenced at the end of 2018. The Northgate Link is due to enter revenue operation in mid-2021.

Figure 3: East Link Extension

The East Link project is a largely at-grade and elevated guideway travelling along existing highway alignments. There is a short section of newly-constructed single tunnel dual track tunnel under downtown Bellevue. The extension travels for 14 miles through Mercer Island, Bellevue and Overlake and ends near the large and expanding Microsoft campus at Redmond Technology station. To cross Lake Washington the alignment runs on what were two lanes of Interstate 90, through two existing Department of Transport tunnels and the existing Homer M Hadley Memorial floating bridge: both of these features have offered some challenges to the designers with the need to fix the overhead contact system to the existing tunnel structure, and to accommodate the movement of the bridge. The East Link will feature ten stations, mainly elevated or at-grade, with one in a partially underground structure. A new Operations and Maintenance facility is under construction in the Spring District, which is about halfway along the alignment between Bellevue and Redmond. This past Spring the project advanced past the halfway mark for construction. Progress is particularly evident along the I90 corridor. In other areas the elevated structures are taking shape, and construction of the station structures is well underway. Rail systems works are about to commence with the installation of prefabricated traction substations and signal houses in the summer.

One integral feature of the East Link project work is the tie-in with the existing alignment at International District / Chinatown in downtown Seattle. Originally planned as an 8 week closure, with bus bridging, a facilitated Value Engineering workshop with our interfacing Civil and Systems contractors produced a plan which enables the same scope to be accomplished in a 10 week phased single-tracking effort starting in January 2020. A detailed schedule of weekend closures and single-tracking has been established to ensure that the various works can be done with minimal impact to the travelling public.

In November 2016, voters approved a large expansion of the Sound Transit light rail network that will expand the network by another 62 miles to 116 miles in total. “ST3” will bring further extension east to Redmond town center, Issaquah and Kirkland, north to Everett and a connection between West Seattle and Ballard through new tunnels under downtown Seattle.

Most of the development of the Sound Transit network has been characterized by the delivery of civil and structural contracts separate from the systems contracts. The exception to this has been the 1.6-mile extension from the Seattle-Tacoma Airport south to Angle Lake – this was delivered by a full-scope design-and-build contract and went into service in September 2016. The recently tendered Federal Way project, another eight miles south of Angle Lake is also a full-scope design-and-build package, as is the Downtown Redmond Link Extension, currently in the tendering process. So apart from these three projects, the general approach has been to deliver the Civil and structural elements separately from the Systems.

It may be worth explaining here that by Systems, we mean the train control, the electrification and the communications elements of the light rail system. The Civil Contracts look after the structures, the building management systems, elevators and escalators, access control and most fire life safety elements.

Taking this approach requires careful management of the interfaces between the Civil and the Systems scopes. Sound Transit has established requirements for the identification, detailing and documenting of interfaces. These requirements relate not only to the interfaces between the Systems and the Civil scopes, but also aim to manage interfaces within the Systems elements, and indeed within the Civil. The Sound Transit approach relies on the diligent application and management of three elements: a Systems

Under construction

Northgate 2021

University of Washington Overlake Transit

Center 2023

Lynnwood 2024

SeaTac Airport Angle Lake

Federal Way 2024

Bellevue Transit Center 2023

International District Station

Westlake

Redmond 2024

Northgate 2021

University of Washington Overlake Transit

Center 2023

SeaTac Airport Angle Lake

Bellevue Transit Center 2023

International District Station

Westlake

Everett 2036

Northgate 2021

University of Washington

Overlake Transit Center 2023

Lynnwood 2024

Alaska Junction 2030

SeaTac Airport Angle Lake

Federal Way 2024

Tacoma Dome 2030

Issaquah 2041

South Kirkland 2041 Ballard

2035

Bellevue Transit Center 2023 International

District Station Westlake

Redmond 2024

10 miles 10 miles 10 miles

ST2 Expansions ST3 Expansions

Figure 4: Expansion of Sound Transit network i l di ST3

Operational line

Integration Program (SIP), the Design Integration Plan (DIP) and the Coordinated Installation Program (CIP).

The SIP is the overall process through which interfaces are identified, design and construction inputs for the resolution of the interfaces are obtained, and the resolution of the interface is recorded. The DIP works within the SIP to ensure that design workstreams are aligned, that interfaces between design elements are fully identified and resolved. The CIP is a workstream which is required in both Civil and Systems Contracts that ensures regular communication and coordination of the Systems Contractor and the Civil Contractors’ schedules, encourages construction interfaces to be identified and resolved, and deals with physical interfaces such as access, methodologies and spatial layouts. The CIP also encourages the Systems Contractor and the Civil Contractors to identify risks that could exist due to the temporal separation of the two types of contract – where work done by the Civil Contractor, that interfaces with the Systems Contractor’s work, but will be completed long before the Systems Contractor arrives on site, for example.

Sound Transit and the Systems contractor have deployed a number of experienced systems integration staff to the project, and these staff are liaising regularly with the Civil contractor-appointed integration point of contact. Generally, the process has worked constructively, but there have been examples of interface problems arising that have caused the wider team to review some of the approaches that have been taken in systems integration.

At the Northgate Parking Garage schedule pressure meant that Civil contractor and Systems contractor had to share the space and work alongside each other, which is a familiar refrain. Civil contractor’s approach to installation of conduit was based on installing as much linear conduit as possible, leaving the more time-consuming ends of the conduit runs to be done later. The Systems contractor was left with mostly complete, but still unusable raceways with the substantial completion date looming. Communication with the Civil contractor through the CIP process enabled the Civil contractor to adjust their approach so that they would finish a section of conduit entirely before moving on to the next section, meaning an earlier start to cable pulling by the Systems contractor.

Figure 5: re-organized coordination markup of Station Signal Room

At the underground Roosevelt Station on the Northgate Link, the Civil Contractor was scoped to install various equipment including access control hardware and clean agent fire suppression equipment in the Signal room prior to the Systems contractor installing the train control cabinets and uninterruptible power supply. The layout of the room was agreed as part of the CIP. However, when the Systems contractor arrived at site to start installation it was found that the Civil contractor’s installation had diverged from the coordinated layout, and the train control equipment could no longer be installed as planned (see photo inserts in figure 5). The general layout of the room had been entirely revised. While the Systems equipment re-organization was relatively straightforward and no critical delay was suffered, it is interesting to understand how the failure in coordination occurred.

The Civil and Systems Contractors had diligently followed the CIP process and coordinated drawings had been produced on which both contractors’ equipment was laid out. Prior to the installations starting, the Civil designers suggested that an improved layout may be achieved if the equipment layout were rotated through 90 degrees. The request was circulated to interfacing parties including the Civil and Systems designers and the Systems contractor. In this case the Systems contractor advised that they had completed their engineering according to the original coordinated layout and so the request to rotate the layout was refused. In the meantime, however, the Civil designers had proceeded with the change, and this had already been communicated to the Civil contractor. The Systems team’s rejection of the rotation proposal was not communicated to the Civil designers or the Civil contractor, nor was the fact that it was not communicated fed back to the Systems team. So, the Civil contractor proceeded with the rotated design and the Systems contractor assumed that the design had not changed.

Figure 6: Roosevelt Station MVSS room showing installation clashes

At Roosevelt Medium Voltage Substation (MVSS) room, the Civil contractor had installed the air-handling equipment and ductwork before the Systems contractor arrived on site to install the MVSS equipment. The layout had been coordinated using a digital BIM space-planning and clash-detection software and adjustments had been made to ensure everything could be accommodated. Yet when the Systems contractor installed the MVSS equipment the clashes above were identified. In figure 6 on the left, there is a clear clash between the ductwork and the MVSS cabinet door opening. In figure 6 on the right, the rear doors of the equipment are impeded by an air-handling unit. On investigation it was identified that the input provided to the BIM model by the Systems contractor comprised only the dimensions of the MVSS equipment – the contractor had not established at that stage exactly where in the room the equipment had to be located. It is assumed that the operators of the BIM model placed the equipment a location where it appeared to fit and that concluded the coordination process! In this case, a simple re-positioning on site was effected in the days following the initial installation.

On the East Link project the Civil work scope is divided into five separate packages, plus a tunneling contract. E130 spans the tie-in to the existing System at IDS, across the I90 floating bridge and Mercer Island and ends in South Bellevue. E320 then resumes the elevated and at grade alignment in South Bellevue, ending just before E335 assumes the work to transition into the tunnel under downtown Bellevue, emerging at the Transit Center and crossing I405, a major north/south artery running through downtown Bellevue, bypassing Seattle. E335 then ends between two at-grade stations, where E340 assumes the street-running potion of the alignment through the Spring District into Bel-Red, where our design build contract, E360 finishes the extension at the terminus station in Overlake on the Microsoft campus. Due to the number of different contractors, OCS foundations issues were identified as a possible risk.

Figure 7: examples of OCS pole foundation installation problems

The Civil Contractors responsible for the construction of the guideway structures have been scoped to provide the foundations for the poles for the Overhead Contact System for the electrification system. Overall there are approximately 1500 poles in the electrification system and in the vast majority of cases the quality of the installed foundations is excellent, with very few problems encountered. The above two examples are exceptions to the rule, where a misunderstanding of the function of the foundations, and of the methods used in installing the poles has led to clear interface problems. The photograph to the left in figure 6 shows an anchor foundation: these are used to anchor a guy wire that is under high tension to keep the overhead wire taught. In this case, the installed permanent security fence would clearly interfere with the guy wire. In the example in figure 7 on the right, a concrete wall has been installed immediately behind the pole foundation. In order to install it, the pole is suspended by a track-based crane while the base is bolted to the foundation. In this case the presence of the wall around the back of the foundation would make this a very difficult operation, especially considering how the rear nuts should be adjusted and torqued.

While the percentage of Overhead Contact System foundations on East Link with issues is reasonably low and the ones that have critical defects are fewer still, these problems and those described on Northgate persist despite the SIP/DIP and CIP efforts. Given the status of construction and the potential for more issues, with larger ramifications as we get closer to completion and pre-revenue operations, the construction management team and contractor have looked at ways of improving these coordination processes through the remainder of the projects.

A good start to this endeavor is to understand why these interface issues occur. Is it timing, such as our coordinated installation drawings being agreed while they are too conceptual and the overall design is not mature enough? Is it lack of follow-up by interfacing contractors to monitor and control changes to our coordinated drawings and BIM models? Is it that when both interfacing contractors have the same or similar contract requirements to lead a coordination effort, one assumes the other will take the lead and in

the end neither takes that role? The answer is likely “all of the above” and more. In our discussions with the Systems contractor on how to improve the process on East Link, by mutual agreement the Systems contractor will be taking the lead of the Coordinated Installation Program, setting the agenda and bringing their lessons learned to inform the task of coordination installations in the stations and on the guideway. The process will continue to be led by the Civil contractors on Northgate, as it’s an established and improved process, taking lessons from the Northgate parking garage.

As for the Owner and Construction Management Consultant team, we will be ensuring that the established processes are followed, and more emphasis is placed on the quality and completeness of the design information that is used as input to the integration analysis, and we will ensure continual review of established, agreed coordinated designs to catch diversions from those agreements as the interfacing designs mature and possibly adjust. It seems clear that a threat to successful coordination is diverging designs making prior agreements on integration out-of-date or invalid. Further, it is imperative that communications are improved such that any decisions to diverge from a coordinated design are communicated to those interfacing parties who need to know, so that the overall grand design can be brought back in to a coordinated, integrated state.

How is success defined for these efforts? What is the expectation of perfectly coordinated interfaces? The difficulty in measuring this success is that a properly coordinated design, successful contractor-led design and construction integration or a high-functioning coordinated installation process have no measurable indicators – only that everything went as planned. The only thing that is quantifiable is the cost of coordination errors, omissions and lack of coordinated work planning.

LIST OF FIGURES:

Figure 1: Sound Transit light rail vehicles on Central Link, with Mount Rainier looking on

Figure 8: Northgate Link Extension

Figure 9: East Link Extension

Figure 10: Expansion of Sound Transit network including ST3

Figure 11: re-organized coordination markup of Station Signal Room

Figure 12: Roosevelt Station MVSS room showing installation clashes

Figure 13: examples of OCS pole foundation installation problems

Sound Transit Expansion and challenges for Systems Integration

Conrad Fawcett – Mott MacDonald

Ben Neeley – Sound Transit

2

Link light rail• University of Washington,

Capitol Hill, Downtown Seattle,Sea-Tac Airport, Angle Lake

• Tacoma Dome to Theater District

Sounder rail• Everett to Seattle• Lakewood/Tacoma to Seattle

ST Express bus• 28 regional bus routes

Current service

3

Link light rail – Northgate Link• U District, Roosevelt, Northgate – under construction

Sounder rail• Sumner and Puyallup stations parking and access

improvements

2021

4

2023Link light rail• Mercer Island, Bellevue, Spring District, Redmond

(Overlake) – under construction

Sounder rail• Kent and Auburn stations parking and access

improvements

5

2024Link light rail• Shoreline, Mountlake Terrace, Lynnwood – in procurement• SE and Downtown Redmond – in procurement• Kent/ Des Moines, Federal Way – procurement finalized,

contract awarded

Sounder rail• Sounder north added parking and access improvements

Bus Rapid Transit• I-405 BRT – Lynnwood to Burien• SR 522 BRT – Shoreline to Bothell

Bus improvements• North Sammamish Park & Ride

6

2030Link light rail• Alaska Junction, Avalon, Delridge – concept stage• South Federal Way, Fife, East Tacoma, Tacoma Dome –

concept stage

7

2035Link light rail and new downtown tunnel• Ballard, Interbay, Smith Cove,

Seattle Center, South Lake Union, Denny, Midtown –concept stage

8

2036Link light rail• Everett, SR 526/Evergreen,

SW Everett Industrial Center, Mariner, Ash Way, West Alderwood – concept stage

Sounder rail• DuPont and Tillicum• Sounder south capacity and access improvements

completed

9

2039Link light rail• Tacoma Link Extension to Tacoma Community College

10

2041Link light rail• South Kirkland, Richards Road, Eastgate / Bellevue

College, Issaquah

11

Currently under ConstructionNorthgate Link (NG)• 3.5 miles, two stations, mostly tunnel• From UW to Northgate on map

East Link (EL)• 13.5 miles, • From Downtown Seattle to Overlake on map

Contracting approach (current)• NG/EL Systems let as a single

contract for both lines

• GC/CM Contract form, heavy civils variant

• Lynnwood Link included as an option• To be determined in 2020

All Civils and Stations works let separately

• Blend of GC/CM, Bid-Build, and Design Build

Owner(Sound Transit)

Contractor

Construction Management

Consultant(MM & STV)

Current status of construction

• Overall 15% complete (Systems)• Most engineering submittals already in place• Interface definition is in place (never complete!)• Subcontracts for all major works are awarded• Work on site started end 2018 on Northgate Link

• First station transformers energized June 2019

• Started in August 2019 on East Link

Systems Integration on the project

Run three processes:• Systems Integration ProgramIntegration of hardware and software in both new and existing

Systems within the Systems contractor scope as well as the interfacing Civil Contracts

• Design Integration PlanEngineering management plan to ensure that all elements of design

are fully compatible and integrated• Coordinated Installation ProgramProgram where interfacing contracts are required to meet and review

coordinated installation drawings and develop coordinated schedules

Current Integration Efforts

4-Car Consists Modifications – now through Nov 2019• Make tunnel ventilation modifications • Enable currently disabled fans at terminal station• Allows for higher train capacity during increased headways.

Connect 2020 – now through March 2020• 10 week Single-Track Operation (replaces planned shutdown of

portion of System)• Allows phased tie-in work of major civil and track construction for

East Link Extension.• Early Signal upgrades and reconfiguration along with eventual OCS

and Traction Electrification modifications.

Systems Integration on the project

Run three processes:• Systems Integration Program• Design Integration Plan• Coordinated Installation Program

Focus on SIP and CIP

Systems Integration Program• Standard approach from start of project• Interfaces identified and tracked on a matrix• For each, Interface Definition Document

Coordinated Installation Program• Focus on schedule and space coordination• Coordination and collaboration mandated by Contract

Is it working?

Many important benefits have accrued• Safety of site operations through collaboration• Access for systems equipment has been provided smoothly• Installation and energization of 26kV gear involved local utility,

Systems Contractor and Stations Contractor – intensive collaboration

• Energization procedures ran safely and smoothly, involved Systems and Civils

• Interface Definitions are largely in place• Interface problems have been identified early

Systems Integration: is it working?

It’s complicated:• Underground stations – space at a premium; pressure on

accommodating all the equipment• Effective coordination at design stage is only part of the

solutionWhat is success?

• It’s difficult to assess what future problems are avoided by successful integration efforts

• Yet some problems will persist, so where the cumulative benefit of a good SIP is hard to quantify, the failures in that program will be quantifiable in changes, delays, etc.

Spatial Coordination

What happened?

Coordinated BIM model was produced, but…certain position parameters were not requested, provided, entered

• BIM operators made assumptions that transferred on to coordinated drawings

• When equipment cabinets installed…problem

• In this case, not much time wasted

Spatial coordination

What happened?

Coordinated drawings were produced and signed off early in design/engineering processStations contractor proposed a change in orientation

• Stations team accepted change, but…• Systems team rejected change. Rejection was not

communicated.• Stations team proceeded with the re-oriented layout• Systems Contractor arrived on site…problem

• Coordinated drawings were not maintained!

Construction coordination

What happened?

Overhead Contact System pole foundations –constructed by Civils Contractor• CIP meetings focused on the position of bolts

and location of foundation relative to track• No-one asked about other constraints• Constructability of the OCS was not understood• Other constraints (eg. proximity of wall / fence)

were not understood

A learning experience?

With hindsight• Interface definition needs to be wider, to look at potential

interfaces as well as actual interfaces• Need to adjust to a more risk-based approach, such as

when looking at hazards. • The “what if” questions

A learning experience?

Some foresight:• Focus and emphasize the communication of interfaces

• Contractors need to discuss the construction of their side of the interfaces – run through the means and methods of construction

• Definition and coordination of interfaces need to be maintained to keep them up to date with developing design / engineering – a continuing process!

• Contract language needs to make both sides accountable for interfaces, if not accountable to each other