State Route 99 (SR 99), also known as the Pacific Highway, is a

state highway A state highway, state road, or state route (and the equivalent provincial highway, provincial road, or provincial route) is usually a road that is either Route number, numbered or maintained by a sub-national state or province. A road numbered ...

in the

Seattle metropolitan area The Seattle metropolitan area is an urban conglomeration in the U.S. state of Washington (state), Washington that comprises Seattle, its surrounding Satellite city, satellites and suburbs. The United States Census Bureau defines the Seattle–T ...

, part of the U.S. state of

Washington Washington most commonly refers to: * George Washington (1732–1799), the first president of the United States * Washington (state), a state in the Pacific Northwest of the United States * Washington, D.C., the capital of the United States ** A ...

. It runs from

Fife Fife ( , ; ; ) is a council areas of Scotland, council area and lieutenancy areas of Scotland, lieutenancy area in Scotland. A peninsula, it is bordered by the Firth of Tay to the north, the North Sea to the east, the Firth of Forth to the s ...

to Everett, passing through the cities of

Federal Way Federal Way is a city in King County, Washington, United States and part of the Seattle metropolitan area. One of the most recently incorporated cities in the county, its population was 101,030 at the 2020 census. Federal Way is the 10th most p ...

, SeaTac,

Seattle Seattle ( ) is the most populous city in the U.S. state of Washington and in the Pacific Northwest region of North America. With a population of 780,995 in 2024, it is the 18th-most populous city in the United States. The city is the cou ...

Shoreline A coast (coastline, shoreline, seashore) is the land next to the sea or the line that forms the boundary between the land and the ocean or a lake. Coasts are influenced by the topography of the surrounding landscape and by aquatic erosion, su ...

, and

Lynnwood Lynnwood is a city in Snohomish County, Washington, United States. The city is part of the Seattle metropolitan area and is located north of Seattle and south of Everett, near the junction of Interstate 5 and Interstate 405. It is the four ...

. The route primarily follows arterial streets, including Aurora Avenue, and has several

freeway A controlled-access highway is a type of highway that has been designed for high-speed vehicular traffic, with all traffic flow—ingress and egress—regulated. Common English terms are freeway, motorway, and expressway. Other similar terms ...

segments, including the tolled

SR 99 Tunnel The State Route 99 tunnel, also known as the Alaskan Way Viaduct replacement tunnel, is a bored highway tunnel in the city of Seattle, Washington, United States. The , double-decker tunnel carries a section of State Route 99 (SR 99) unde ...

Downtown Seattle Downtown is the central business district of Seattle, Washington. It is fairly compact compared with other city centers on the U.S. West Coast due to its geographical situation, being hemmed in on the north and east by hills, on the west by ...

. SR 99 was officially named the William P. Stewart Memorial Highway by the state legislature in 2016, after a campaign to replace an unofficial moniker honoring Confederate president

Jefferson Davis Jefferson F. Davis (June 3, 1808December 6, 1889) was an American politician who served as the only President of the Confederate States of America, president of the Confederate States from 1861 to 1865. He represented Mississippi in the Unite ...

. SR 99 was originally a section of U.S. Route 99 (US 99), which was once the state's primary north–south highway before the construction of I-5. US 99 was created in 1926 and replaced earlier local roads that date back to the 1890s and state roads designated as early as 1913. The highway was moved onto the

Alaskan Way Viaduct The Alaskan Way Viaduct ("the viaduct" for short) was an elevated freeway in Seattle, Washington, United States, that carried a section of Washington State Route 99, State Route 99 (SR 99). The double-decked freeway ran north–south along the ...

in 1953, replacing a congested stretch through Downtown Seattle, and other sections were built to expressway standards in the 1950s. US 99 was ultimately replaced by the Tacoma–Everett section of

Interstate 5 Interstate 5 (I-5) is the main north–south Interstate Highway System, Interstate Highway on the West Coast of the United States, running largely parallel to the Pacific coast of the contiguous U.S. from Mexico to Canada. It travels thro ...

(I-5), which opened in stages between 1965 and 1969. The route was decertified in 1969, and SR 99 was created to keep segments of the highway under state control. After decades of crime on some sections of SR 99, various city governments funded projects to beautify the highway and convert it into a

boulevard A boulevard is a type of broad avenue planted with rows of trees, or in parts of North America, any urban highway or wide road in a commercial district. In Europe, boulevards were originally circumferential roads following the line of former ...

. A section of the highway in Tukwila was transferred to city control in 2004, creating a gap in the route between the interchanges of SR 518 and SR 599. The Alaskan Way Viaduct was closed on January 11, 2019, and was replaced with a downtown bored tunnel that opened on February 4, 2019. The replacement project was spurred by the 2001 Nisqually earthquake, which damaged the viaduct and left it vulnerable to further damage, as well as city plans to revitalize the Seattle waterfront. The $3 billion

megaproject A megaproject is an extremely large-scale construction and investment project. A more general definition is "Megaprojects are temporary endeavours (i.e. projects) characterised by: large investment commitment, vast complexity (especially in org ...

was mired in planning delays for several years before construction began in 2011 with the partial demolition of the viaduct. The tunnel was constructed using

Bertha Bertha is a female Germanic name, from Old High German ''berhta'' meaning "bright one". It was usually a short form of Anglo Saxon names ''Beorhtgifu'' meaning "bright gift" or ''Beorhtwynn'' meaning "bright joy". The name occurs as a theonym, s ...

, the world's largest

tunnel boring machine A tunnel boring machine (TBM), also known as a "mole" or a "worm", is a machine used to excavate tunnels. TBMs are an alternative to drilling and blasting methods and "hand mining", allowing more rapid excavation through hard rock, wet or dry so ...

at the time of its launch in 2013, which had a two-year halt and completed its bore in 2017. The viaduct was demolished in 2019, leaving room for an expanded park promenade on

Alaskan Way Alaskan Way, originally Railroad Avenue, is a major north-south street in Seattle, Washington, that runs along the Elliott Bay waterfront from just north of S. Holgate Street in the Industrial District—south of which it becomes East Marginal ...

that is planned to be completed in 2024.

Route description

SR 99 follows a section of former

U.S. Route 99 U.S. Route 99 (US 99) was a main north–south United States Numbered Highway on the West Coast of the United States until 1964, running from Calexico, California, on the Mexican border to Blaine, Washington, on the Canadian border. It w ...

(US 99) within the

, from

to southern Everett. It is officially designated as the William P. Stewart Memorial Highway, but is commonly known as the Pacific Highway or by one of its local names. The entire highway is listed as part of the National Highway System, a national network of roads identified as important to the national economy, defense, and mobility. A section of the highway from Tukwila to

is also designated as a Highway of Statewide Significance by the

state legislature A state legislature is a Legislature, legislative branch or body of a State (country subdivision), political subdivision in a Federalism, federal system. Two federations literally use the term "state legislature": * The legislative branches of ...

. The

Washington State Department of Transportation The Washington State Department of Transportation (WSDOT or WashDOT, both ) is a governmental agency that constructs, maintains, and regulates the use of transportation infrastructure in the U.S. state of Washington (state), Washington. Establi ...

(WSDOT) estimates that average traffic volumes on SR 99, measured in terms of

annual average daily traffic Annual average daily traffic (AADT) is a measure used primarily in transportation planning, transportation engineering and retail location selection. Traditionally, it is the total volume of vehicle traffic of a highway or road for a year divided ...

for 2016, range from a minimum of 17,000 vehicles on Everett Mall Way to a maximum of 97,000 at the

First Avenue South Bridge The First Avenue South Bridge is a pair of double-leaf bascule bridges built between 1956 and 1998 that carry State Route 99 over the Duwamish River about three miles (5 km) south of downtown Seattle, Washington. The present day northb ...

in Seattle.

Fife to SeaTac

SR 99 begins in Fife as an extension of 54th Avenue East at a

partial cloverleaf interchange A partial cloverleaf interchange or parclo is a modification of a cloverleaf interchange. The design has been well received, and has since become one of the most popular freeway-to-arterial interchange designs in North America. It has also bee ...

with

. Immediately north of the interchange, SR 99 turns east onto Pacific Highway and passes the

Emerald Queen Casino The Puyallup Tribe of Indians ( ; ; commonly known as the Puyallup Tribe) is a federally-recognized tribe of Puyallup people from western Washington state, United States. The tribe is primarily located on the Puyallup Indian Reservation, altho ...

, a gambling and hotel facility operated by the

Puyallup Tribe The Puyallup Tribe of Indians ( ; ; commonly known as the Puyallup Tribe) is a federally-recognized tribe of Puyallup people from western Washington state, United States. The tribe is primarily located on the Puyallup Indian Reservation, altho ...

, and a commercial district at the outskirts of Fife. The highway makes a gradual turn to the north, parallel to Interstate 5 and the West Fork of Hylebos Creek, and enters Milton. SR 99 travels north along a ridge and crosses into

King County King County is a county located in the U.S. state of Washington. The population was 2,269,675 in the 2020 census, making it the most populous county in Washington, and the 12th-most populous in the United States. The county seat is Seattle ...

, turning northeast and entering the city of

. The road cuts through a forested part of the Hylebos basin near West Hylebos Wetlands Park and reaches a commercial district surrounding Kitts Corner. At Kitts Corner, the highway intersects the western section of State Route 18, which continues east to an interchange with I-5 and onto a freeway traveling towards Auburn and Covington. SR 99 continues due north through Federal Way's main commercial strip and passing Celebration Park,

The Commons at Federal Way The Commons at Federal Way (formerly SeaTac Mall) is a regional shopping mall located in Federal Way, Washington, and is the only indoor shopping center in the city. Steadfast Commercial Properties changed the mall's name to The Commons at Feder ...

, and Steel Lake. The highway gains a set of

high-occupancy vehicle lane A high-occupancy vehicle lane (also known as an HOV lane, carpool lane, diamond lane, 2+ lane, and transit lane or T2 or T3 lanes) is a restricted traffic lane reserved for the exclusive use of vehicles with a driver and at least one passenger, ...

s that are also open to right turns into parking lots and side streets. From northern Federal Way to the Redondo area of

Des Moines Des Moines is the List of capitals in the United States, capital and List of cities in Iowa, most populous city in the U.S. state of Iowa. It is the county seat of Polk County, Iowa, Polk County with parts extending into Warren County, Iowa, Wa ...

, SR 99 is

concurrent Concurrent means happening at the same time. Concurrency, concurrent, or concurrence may refer to: Law * Concurrence, in jurisprudence, the need to prove both ''actus reus'' and ''mens rea'' * Concurring opinion (also called a "concurrence"), a ...

with SR 509, which continues southwest to Dash Point State Park and northwest to downtown Des Moines, for . The two highways pass

Saltwater State Park Saltwater State Park is a plot of second-growth timber on Puget Sound in the city of Des Moines, Washington, United States. The main attraction is of saltwater beachfront, including a sandy swimming beach in the southwest corner, and rocky tidef ...

and the former Midway

landfill A landfill is a site for the disposal of waste materials. It is the oldest and most common form of waste disposal, although the systematic burial of waste with daily, intermediate and final covers only began in the 1940s. In the past, waste was ...

before splitting near

Highline College Highline College is a public community college in Des Moines, Washington. Highline was founded in 1961 as the first community college in King County, Washington. The main campus covers . , there were approximately 17,000 students and 350,000 al ...

at an intersection with Kent Des Moines Road ( SR 516). SR 99 then enters the city of SeaTac and continues north as International Boulevard, passing a federal detention center and light rail station on the southwest side of Angle Lake. The highway runs along the east side of

Seattle–Tacoma International Airport Seattle–Tacoma International Airport is the primary international airport serving Seattle and its surrounding metropolitan area in the U.S. state of Washington. It is in the city of SeaTac, which was named after the airport's nickname Se ...

and its expressway, serving the airport's terminals, parking garage, light rail station, and nearby hotels. SR 99 terminates at an interchange with SR 518 in southern Tukwila, near the airport's consolidated

rental car A car rental, hire car or car hire agency is a company that rents automobiles for short periods of time to the public, generally ranging from a few hours to a few weeks. It is often organized with numerous local branches (which allow a user to ...

facility and the Tukwila light rail station. A section of International Boulevard in Tukwila forms the gap between the two segments of SR 99.

Seattle and Aurora Avenue

SR 99 resumes at the north end of Tukwila International Boulevard and supersedes SR 599, a short freeway connecting to I-5, near the

Duwamish River Edmonds plans to add widened sidewalks with planted buffer zones, new crosswalks, and turn lane pockets to its section of SR 99 beginning in 2022. The city of Seattle also plans to improve its section of Aurora Avenue North, but funding shortages and the timing of WSDOT repaving projects have led to a lack of sidewalks along some sections of the street. The Move Ahead Washington package, passed in 2022, includes $50 million in funds to rebuild sections of Aurora Avenue to include sidewalks, bicycle lanes, and landscaping. The Aurora Bridge, part of the expressway linking Aurora Avenue to downtown Seattle, was the site of frequent suicide jumps until a set of

emergency phone An emergency telephone is a public telephone provided for making calls to emergency services. Roadside emergency telephones Although it is difficult to determine when and where the earliest highway emergency phones were developed, undoubtedly ...

s and new fences were installed in 2011 at a cost of $4.6 million to deter would-be jumpers. The bridge and its

expansion joint A expansion joint, or movement joint, is an assembly designed to hold parts together while safely absorbing temperature-induced expansion and contraction of building materials. They are commonly found between sections of buildings, bridges, s ...

s underwent a major

seismic retrofit Seismology (; from Ancient Greek σεισμός (''seismós'') meaning "earthquake" and -λογία (''-logía'') meaning "study of") is the scientific study of earthquakes (or generally, quakes) and the generation and propagation of elastic ...

that was completed in 2012 at a cost of $5.7 million; the retrofit was followed by a repainting and repaving project that was completed in two stages between 2016 and 2018 at a cost of $35 million. On September 24, 2015, a collision between an amphibious

Duck tour Duck tours (or, more formally, amphibious tours), are tours that take place on purpose-built amphibious tour buses and (modified) surplus amphibious military vehicles, like DUKWs (''"Ducks"'') and LARC-Vs. They are often offered as tourist at ...

vehicle and a

charter bus A bus (contracted from omnibus, with variants multibus, motorbus, autobus, etc.) is a motor vehicle that carries significantly more passengers than an average car or van, but fewer than the average rail transport. It is most commonly used ...

on the Aurora Bridge killed four people and injured 50 more. The incident raised questions regarding the safety of Aurora Bridge, which lacks a median barrier and is the narrowest six-lane bridge in the state, with a lane width of . Other sections of Aurora Avenue were retrofitted to install median barriers in 1973, and the state government considered a 2003 plan to put barriers on the bridge and relocate the sidewalks to compensate for the additional weight but ultimately deferred any improvements. In the aftermath of the crash and its three-year-long court case, WSDOT and the

Seattle Department of Transportation The Seattle Department of Transportation (SDOT) is a municipal government agency in Seattle, Washington that is responsible for the maintenance of the city's transportation systems, including roads, bridges, and public transportation. The agenc ...

have disagreed over whether to install a center barrier or median zipper system, and which agency would be responsible for funding either option.

Viaduct replacement and tunnel project

Proposals and earthquake studies

Proposals to replace the Alaskan Way Viaduct date back to the 1970s during attempts to revitalize the city's waterfront for tourism and recreation rather than traditional industrial uses. A similar double-decker freeway, the

Cypress Street Viaduct The Cypress Street Viaduct, often referred to as the Cypress Structure or the Cypress Freeway, was a , raised two-deck, multi-lane (four lanes per tier) freeway constructed of reinforced concrete that was originally part of the Nimitz Freeway ( ...

Oakland, California Oakland is a city in the East Bay region of the San Francisco Bay Area in the U.S. state of California. It is the county seat and most populous city in Alameda County, California, Alameda County, with a population of 440,646 in 2020. A major We ...

, collapsed during the

Loma Prieta earthquake On October 17, 1989, at 5:04 p.m. PST, the Loma Prieta earthquake occurred at the Central Coast of California. The shock was centered in The Forest of Nisene Marks State Park in Santa Cruz County, approximately 10 mi (16 km) ...

in 1989 and killed 42 people, leading to intensified calls to replace the viaduct due to the realized earthquake risk. A 1995 study commissioned by the state government after the

Kobe earthquake The Great Hanshin Earthquake (, ) occurred on January 17, 1995, at 05:46:53 JST in the southern part of Hyōgo Prefecture, Japan, including the region of Hanshin. It measured 6.9 on the moment magnitude scale and had a maximum intensity of 7 o ...

found vulnerabilities in the Alaskan Way Viaduct's design that could cause severe damage and collapse during a major earthquake, along with

liquefaction In materials science, liquefaction is a process that generates a liquid from a solid or a gas or that generates a non-liquid phase which behaves in accordance with fluid dynamics. It occurs both naturally and artificially. As an example of t ...

risks due to the underlying

reclaimed land Land reclamation, often known as reclamation, and also known as land fill (not to be confused with a waste landfill), is the process of creating new land from oceans, seas, riverbeds or lake beds. The land reclaimed is known as reclamatio ...

that the highway was built on. The study estimated that it would cost $118 million (equivalent to $ in dollars) to demolish the viaduct, $344 million (equivalent to $ in dollars) to retrofit the structure for earthquake resistance, and $530 million (equivalent to $ in dollars) to build a new elevated freeway to replace it; other options included replacing the freeway with a tunnel or a surface boulevard with

public transit Public transport (also known as public transit, mass transit, or simply transit) are forms of transport available to the general public. It typically uses a fixed schedule, route and charges a fixed fare. There is no rigid definition of wh ...

on Alaskan Way, similar to

San Francisco San Francisco, officially the City and County of San Francisco, is a commercial, Financial District, San Francisco, financial, and Culture of San Francisco, cultural center of Northern California. With a population of 827,526 residents as of ...

's Embarcadero. On February 28, 2001, the Nisqually earthquake struck the Seattle area with strong shaking that caused signs of visible damage on the Alaskan Way Viaduct. The freeway was shut down for inspections, which found small cracks and other minor damage to non-structural elements that allowed it to reopen within 26 hours. Four more closures were ordered later in March and April due to pieces of concrete dropping onto the streets below, requiring emergency repairs to add steel rods to reinforce the columns. The first repairs were completed in November at a cost of $1.8 million and a set of new vehicle weight restrictions were implemented; in total, $14.5 million was spent on various repairs due to earthquake damage. Annual inspections and continued monitoring found that the earthquake had caused settling of up to into the soil and weakened connections between the columns and highway decks. Additional investigations also found unrelated damage to the underlying

seawall A seawall (or sea wall) is a form of coastal defense constructed where the sea, and associated coastal processes, impact directly upon the landforms of the coast. The purpose of a seawall is to protect areas of human habitation, conservation, ...

, which would need to be rebuilt to prevent a resulting collapse of the viaduct. An ongoing state study investigating a viaduct replacement strategy was accelerated by the state legislature using $5 million in funds, while a separate engineering study suggested immediate demolition of the structure due to a 1-in-20 chance of collapse in an earthquake within the next decade. In late 2001, WSDOT began work on an

environmental impact statement An environmental impact statement (EIS), under United States environmental law, is a document required by the 1969 National Environmental Policy Act (NEPA) for certain actions "significantly affecting the quality of the human environment". An E ...

(EIS) for the viaduct replacement project using emergency funds from the state legislature and consulted the city government and community leaders to generate concepts. By the following year, a set of 76 concepts organized into four general alternatives were presented for public feedback. Among the options were an elevated freeway similar to the current viaduct and several tunnel concepts, including a bored tunnel, a two-level

cut-and-cover A tunnel is an underground or undersea passageway. It is dug through surrounding soil, earth or rock, or laid under water, and is usually completely enclosed except for the two Portal (architecture), portals common at each end, though ther ...

tunnel, and a mined tunnel carrying one direction of traffic. Five finalist options were paired with the seawall replacement and evaluated in June 2002, with costs ranging from $3.5 billion for a rebuilt viaduct to $8.8–$11.6 billion for various tunnel designs.

Tunnel concept, advisory votes, and subprojects

The tunnel plan was endorsed by WSDOT and the city council based on public support for waterfront revitalization, but design changes would be needed to bring down its cost. After voters rejected a statewide

gas tax A fuel tax (also known as a petrol, gasoline or gas tax, or as a fuel duty) is an excise tax imposed on the sale of fuel. In most countries, the fuel tax is imposed on fuels which are intended for transportation. Fuel tax receipts are often dedica ...

referendum that would have funded a portion of the project's cost, WSDOT and the city government drafted new cost-saving concepts for a shorter tunnel and a surface boulevard that were included in the five options evaluated by the draft EIS in 2004. The six-lane, $4 billion tunnel option was chosen as the preferred alternative by WSDOT in late 2004, despite backlash from activists groups who favored a rebuilt viaduct or a waterfront boulevard. The state legislature passed an $8.5 billion gas tax program in 2005, allocating $2 billion in funding for the viaduct replacement. A supplemental EIS was prepared in 2006 to include new project requirements for the Battery Street Tunnel area and evaluate the cut-and-cover tunnel and elevated options. A pair of advisory, non-binding

ballot measure A referendum, plebiscite, or ballot measure is a Direct democracy, direct vote by the Constituency, electorate (rather than their Representative democracy, representatives) on a proposal, law, or political issue. A referendum may be either bin ...

s was held in March 2007 to find a consensus between the $2.8 billion elevated replacement supported by Governor

Christine Gregoire Christine Gregoire (; née O'Grady; born March 24, 1947) is an American attorney and politician who served as the List of governors of Washington, 22nd governor of Washington, from 2005 to 2013. A member of the Democratic Party (United States), D ...

and a smaller four-lane tunnel with surface public transit improvements that would cost $3.4 billion and was supported by Mayor

Greg Nickels Gregory James Nickels (born August 7, 1955) is an American politician who served as the 51st mayor of Seattle, Washington. He took office on January 1, 2002, and was reelected to a second term in 2005. In August 2009, Nickels finished third in t ...

; Nickel's "hybrid tunnel" proposal was rejected by Gregoire and state legislators prior to the vote based on operational and safety problems identified by WSDOT. Both options were rejected by voters, with 70 percent opposed to the tunnel and 55 percent opposed to the elevated concept. The governments of Washington state, King County, and Seattle agreed to re-evaluate the planning process for the viaduct replacement and split the main proposals from essential safety and traffic improvements that would be included in all alternatives. A $915 million package of projects was approved for immediate construction, beginning with work to strengthen sinking columns in late 2007 and repairs to the Battery Street Tunnel the following year. Although the column strengthening project was declared successful, further inspections found that the Columbia Street onramp had sunk an additional during the nearby construction. The southernmost stretch of the viaduct, between Holgate and King streets, was demolished in October 2011 and replaced with a six-lane elevated freeway that opened the following year at a cost of $115 million. Seattle voters approved a

bond measure A municipal bond, commonly known as a muni, is a bond issued by state or local governments, or entities they create such as authorities and special districts. In the United States, interest income received by holders of municipal bonds is often ...

in 2012 to replace the Alaskan Way Seawall; the project began construction in 2013 and was completed in 2017 at a cost of $410 million, running 21 percent overbudget.

Deep-bored tunnel approved and contested

The state government announced a new timeline for the project in January 2008, with Governor Gregoire declaring her intention to demolish the viaduct by 2012 regardless of Seattle's approval. Eight new concepts for a four-lane replacement were developed by June from a set of priorities developed for SR 99, I-5, and public transit in downtown. The eight options included two surface boulevards with transit improvements, a

one-way couplet A one-way pair, one-way couple, or couplet refers to that portion of a bi-directional traffic facilitysuch as a road, bus, streetcar, or light rail linewhere its opposing flows exist as two independent and roughly parallel facilities. Descriptio ...

, a set of two elevated freeways, an elevated freeway with a rooftop park, and three tunnels: a cut-and-cover tunnel, a lidded trench, and a deep-bored tunnel. Several early concepts, including a bridge across

Elliott Bay Elliott Bay is a part of the Central Basin region of Puget Sound. It is in the U.S. state of Washington, extending southeastward between West Point in the north and Alki Point in the south. Seattle was founded on this body of water in the 1850s ...

and a complete rebuild of the double-decked viaduct, were rejected by the panel of public officials. The final decision was delayed until after the

gubernatorial election A governor is an administrative leader and head of a polity or political region, in some cases, such as governors-general, as the head of a state's official representative. Depending on the type of political region or polity, a ''governor'' ma ...

, but would have to meet an end-of-year deadline imposed by the state legislature. In December 2008, two finalists were chosen for further study and consideration by the state legislature: a $2.3 billion elevated freeway and the $2.2 billion surface-transit option. While the deep-bored tunnel was not chosen as one of the two finalists, it remained popular with tunnel activists and was considered separately due to its $4.25 billion cost (equivalent to $ in dollars). On January 13, 2009, Governor Gregoire signed an agreement with Mayor Nickels and King County Executive

Ron Sims Ronald Cordell Sims (born July 5, 1948) is the former deputy secretary of the United States Department of Housing and Urban Development, having served in the position from May 8, 2009 to July 2011. He is also a former King County executive. Sims r ...

to ratify the deep-bored tunnel as the replacement for the Alaskan Way Viaduct, to be completed by 2015. $2.8 billion would be covered by state gas taxes and federal funds, leaving a $1.4 billion shortfall to be filled by the local government and potential

toll Toll may refer to: Transportation * Toll (fee) a fee charged for the use of a road or waterway ** Toll road, a type of road which for which payment is required for passage ** Road pricing, the modern practice of charging for road use ** Road to ...

s. The state legislature passed a bill in April 2009 to commit $2.8 billion in state funding for the tunnel project, which Governor Gregoire signed the following month. In total, more than 90 alternatives were considered before the final agreement was reached in 2009. The tunnel project received $300 million in funds from the Port of Seattle in exchange for design input on the surface boulevard that would replace Alaskan Way. Neighborhood and environmental activist

Mike McGinn Michael McGinn (born December 17, 1959) is an American lawyer and politician. He served as mayor of the city of Seattle, Washington, and is a neighborhood activist and a former State Chair of the Sierra Club. In what was characterized as a "s ...

was elected mayor in 2009, largely on an anti-tunnel platform, and threatened to veto project agreements until the state took responsibility for cost overruns that would fall upon Seattle. The city council approved a non-binding resolution to authorize the tunnel project, pending the outcome of contract bidding, which was completed in December 2010 with the selection of Seattle Tunnel Partners (STP), a consortium led by Dragados USA. STP presented a $1.09 billion plan to use a

, the world's widest, to complete the tunnel by late 2015. WSDOT signed the tunnel construction contract in January 2011, sending a set of contractor agreements to the city council for approval. The state's agreements were approved by the city council in February 2011, shortly before being symbolically

veto A veto is a legal power to unilaterally stop an official action. In the most typical case, a president (government title), president or monarch vetoes a bill (law), bill to stop it from becoming statutory law, law. In many countries, veto powe ...

ed by Mayor McGinn; the veto was overridden by the end of the month—the 10th anniversary of the Nisqually earthquake—with an 8–1 city council majority. McGinn joined other tunnel opposition groups to file a referendum questioning whether the city council had the authority to approve the state and federal agreements. The referendum was initially blocked by a lawsuit filed by the city, but was approved and placed on the August 2011 ballot by a county judge. The referendum was approved by 58 percent of voters on August 16, 2011, authorizing the city's agreements with WSDOT. The

Federal Highway Administration The Federal Highway Administration (FHWA) is a division of the United States Department of Transportation that specializes in highway transportation. The agency's major activities are grouped into two programs, the Federal-aid Highway Program a ...

completed its analysis of the project's final EIS and issued its record of decision with WSDOT later that month, allowing pre-construction activities to begin.

Tunnel boring and viaduct closure

After the demolition of the viaduct's southernmost stretch and its lanes were realigned onto an adjacent bypass in 2012, crews began excavation of a launch pit to house the tunnel boring machine. Local officials, with the notable absence of Mayor Mike McGinn, participated in a ceremonial

groundbreaking Groundbreaking, also known as cutting, sod-cutting, turning the first sod, turf-cutting, or a sod-turning ceremony, is a traditional ceremony in many cultures that celebrates the first day of construction for a building or other project. Such cer ...

was held for the tunnel on June 20, 2012. The tunnel boring machine was manufactured by Hitachi Zosen in

Osaka is a Cities designated by government ordinance of Japan, designated city in the Kansai region of Honshu in Japan. It is the capital of and most populous city in Osaka Prefecture, and the List of cities in Japan, third-most populous city in J ...

, Japan, and named "

" in honor of Mayor

Bertha Knight Landes Bertha Ethel Knight Landes (October 19, 1868 – November 29, 1943) was the first female mayor of a major American city, serving as mayor of Seattle, Washington from 1926 to 1928. After years of civic activism, primarily with women's organization ...

. Bertha arrived in Seattle on April 2, 2013, and its 40 pieces were assembled in the launch pit before tunnel boring began on July 30—setting a record for the world's largest tunnel boring machine. Tunnel boring was halted at near South Main Street in December 2013 after the machine encountered an unknown object that caused it to overheat. The object was found to be a steel pipe and well casing that was left behind by a

groundwater Groundwater is the water present beneath Earth's surface in rock and Pore space in soil, soil pore spaces and in the fractures of stratum, rock formations. About 30 percent of all readily available fresh water in the world is groundwater. A unit ...

research crew for the project in 2002. The pipe caused extensive damage to Bertha's cutterhead and main bearing seal, requiring the excavation of a rescue pit for repairs. Bertha reached the completed excavation pit in March 2015 and the machine's front end was disassembled and lifted to the surface to repair the damage, which was found to be more extensive than previously thought. The repaired cutterhead was lowered into the access pit in August 2015 and tunnel boring resumed on December 22, 2015, reaching past the pit the following month. During the two-year halt in tunnel boring, public officials considered alternative plans to accelerate demolition of the viaduct while awaiting tunnel completion. The project was named one of the worst

boondoggle A boondoggle is a project that is considered a waste of both time and money, yet is often continued due to extraneous policy or political motivations. Etymology "Boondoggle" was the name of the newspaper of the Roosevelt Troop of the Boy Sco ...

s in the United States by several transportation groups and critics, due in part to the stoppage and its high cost. Tunnel boring was halted by Governor

Jay Inslee Jay Robert Inslee ( ; born February 9, 1951) is an American politician and lawyer who served from 2013 to 2025 as the 23rd governor of Washington. A member of the Democratic Party, he served from 1993 to 1995 and again from 1999 to 2012 as a ...

in January 2016 due to the appearance of a sinkhole in Pioneer Square, but resumed the following month. The machine passed under the Alaskan Way Viaduct in April 2016, requiring a closure while the structure was monitored for movement, and reached the halfway mark in October. Bertha completed its bore on April 4, 2017, arriving at the north portal near Aurora Avenue for disassembly, which was completed in August. The tunnel portals and their maintenance areas were completed while work on the double-decker freeway inside the tunnel progressed behind the machine. The Alaskan Way Viaduct permanently closed on January 11, 2019, beginning a three-week realignment of ramps at the portals as ramps were prepared for the opening of the tolled

downtown tunnel The Downtown Tunnel on Interstate 264 (Virginia), Interstate 264 (I-264) and U.S. Route 460 Alternate (Chesapeake–Norfolk, Virginia), U.S. Route 460 Alternate (US 460 Alt.) crosses the Southern Branch Elizabeth River, Southern B ...

on February 4, 2019. The remaining section of the viaduct was demolished in stages between February and November 2019, with some of the of rubble deposited into the Battery Street Tunnel as it was filled and sealed. A three-block section of Aurora Avenue between Denny Way and the new tunnel portal was raised and reconnected to cross-streets in 2019. The Alaskan Way promenade and boulevard project is planned to cost $668 million and will be completed in 2024. The new boulevard will be eight lanes wide in some sections due to requirements placed by WSDOT for

Colman Dock Colman Dock, also called Pier 52, is the primary ferry terminal in Seattle, Washington, United States. The original pier is no longer in existence, but the terminal, now used by the Washington State Ferries system, is still called "Colman Dock ...

access and the Port of Seattle for truck access. The viaduct replacement megaproject is estimated to cost $3.3 billion, with $200 million of construction costs and additional funds for ongoing maintenance to be raised through tunnel tolls that began to be collected on November 9, 2019.

Future projects

In 2022, community activists from the South Park neighborhood proposed removing a freeway section of SR 99 between SR 599 and SR 509 to improve local air quality. A federal grant was announced the following year to study the impact of a possible removal or redesign of the highway through South Park.

Names and designations

The name of SR 99 differs from city to city, with several sections named the Pacific Highway and International Boulevard, a moniker invented by SeaTac for the

1990 Goodwill Games The 1990 Goodwill Games was the second edition of the international multi-sport event created by Ted Turner, which was held between July 20 and August 5, 1990. Following an inaugural edition in Moscow, the second games took place in Seattle, Unit ...

hosted by King County. In Seattle, the highway is known as East Marginal Way and Aurora Avenue North; in Everett, it uses Evergreen Way and Everett Mall Way. A four-block section of former SR 99 between Denny Way and the new tunnel portal was renamed to 7th Avenue North and Borealis Avenue in early 2019 as part of the reconfiguration of Aurora Avenue. The

United Daughters of the Confederacy The United Daughters of the Confederacy (UDC) is an American neo-Confederate hereditary association for female descendants of Confederate Civil War soldiers engaging in the commemoration of these ancestors, the funding of monuments to them, a ...

unsuccessfully lobbied the state legislature in 1939 to designate the entirety of US 99 within the state as part of the national "

Jefferson Davis Highway The Jefferson Davis Highway, also known as the Jefferson Davis Memorial Highway, was a transcontinental highway in the United States in the 1910s and 1920s that began in Arlington County, Virginia, and extended south and west to San Diego, Cali ...

". A pair of

granite Granite ( ) is a coarse-grained (phanerite, phaneritic) intrusive rock, intrusive igneous rock composed mostly of quartz, alkali feldspar, and plagioclase. It forms from magma with a high content of silica and alkali metal oxides that slowly coo ...

markers were installed the following year in Blaine and Vancouver to commemorate the highway, allegedly to recognize Davis's contributions to the territorial development of Washington as U.S.

Secretary of War The secretary of war was a member of the U.S. president's Cabinet, beginning with George Washington's administration. A similar position, called either "Secretary at War" or "Secretary of War", had been appointed to serve the Congress of the ...

. The two markers were removed in 1998 and 2002, and are now located at the privately owned Jefferson Davis Park in Ridgefield. The State House of Representatives unanimously approved a bill in 2002 that would have removed Davis' name from the road, but it was deferred by a State Senate committee. The attempted renaming, led by Snohomish representative Hans Dunshee, generated political controversy and

death threat A death threat is a threat, often made anonymously, by one person or a group of people to kill another person or group of people. These threats are often designed to intimidate victims in order to manipulate their behaviour, in which case a d ...

s against legislators from people opposed to the bill. The bill was revived in May 2016 and was passed unanimously by both houses of the legislature, renaming SR 99 for William P. Stewart, an

African-American African Americans, also known as Black Americans and formerly also called Afro-Americans, are an American racial and ethnic group that consists of Americans who have total or partial ancestry from any of the Black racial groups of Africa. ...

Civil War A civil war is a war between organized groups within the same Sovereign state, state (or country). The aim of one side may be to take control of the country or a region, to achieve independence for a region, or to change government policies.J ...

veteran and early settler in Snohomish. New highway signs for the William P. Stewart Memorial Highway were installed the following year, amid a new wave of Confederate monument removals.

Public transit

SR 99 is a major regional public transit corridor and carries several bus rapid transit routes and a

light rail Light rail (or light rail transit, abbreviated to LRT) is a form of passenger urban rail transit that uses rolling stock derived from tram technology National Conference of the Transportation Research Board while also having some features from ...

line in SeaTac. The highway features

bus lane A bus lane or bus-only lane is a lane restricted to buses, generally to speed up public transport that would be otherwise held up by traffic congestion. The related term busway describes a roadway completely dedicated for use by buses, whilst ...

s and business access and transit lanes (BAT lanes) in several locations to give buses traffic priority while retaining access to right turns.

Pierce Transit Pierce Transit, officially the Pierce County Public Transportation Benefit Area Corporation, is an operator of public transit in Pierce County, Washington. It operates a variety of services, including fixed-route buses, dial-a-ride transportatio ...

route 500 runs on the SR 99 and Pacific Highway corridor between

Tacoma Dome Station Tacoma Dome Station is a train station and transit hub in Tacoma, Washington, United States. It is served by Amtrak trains, the S Line of Sounder commuter rail, the T Line of Link light rail, and buses on local and intercity rout ...

and

Federal Way Transit Center Federal Way Downtown station is a future light rail station at the site of the Federal Way Transit Center, a bus station in Federal Way, Washington, United States. The bus station opened in 2006 and has 1,190 parking spaces available in its par ...

. Through Federal Way and SeaTac, the highway is served by the RapidRide A Line, an rapid bus route that debuted in 2010 and features enhanced bus stops and

transit signal priority Bus priority or transit signal priority (TSP) is a name for various techniques to improve service and reduce delay for mass transit vehicles at intersections (or junctions) controlled by traffic signals. TSP techniques are most commonly associa ...

Sound Transit Sound Transit (ST), officially the Central Puget Sound Regional Transit Authority, is a public transit agency serving the Seattle metropolitan area in the U.S. state of Washington (state), Washington. It manages the Link light rail system in Se ...

Link light rail Link light rail is a light rail system with some rapid transit characteristics that serves the Seattle metropolitan area in the U.S. state of Washington (state), Washington. It is managed by Sound Transit in partnership with local transit pro ...

trains on the 1 Line run along elevated tracks above or near SR 99 from Angle Lake station to Tukwila International Boulevard station at the SR 518 interchange. The Alaskan Way Viaduct carried several non-stop routes connecting Downtown Seattle to

West Seattle West Seattle is a conglomeration of List of neighborhoods in Seattle, neighborhoods in Seattle, Washington, United States. It comprises two of the List of neighborhoods in Seattle, thirteen districts, Delridge, Seattle, Delridge and Southwest, ...

(including the RapidRide C Line) and

Burien Burien ( ) is a suburban city in King County, Washington, United States, located south of Seattle on Puget Sound. As of the 2020 census, Burien's population was 52,066, which is a 56.3% increase since incorporation in 1993, making it the 25th m ...

. Aurora Avenue is served by the

RapidRide E Line The RapidRide E Line is one of eight RapidRide lines (limited-stop routes with some bus rapid transit features) operated by King County Metro in King County, Washington. The E Line began service on February 15, 2014, running from Aurora Village ...

, which carried 18,000 passengers daily in 2017 and is the busiest bus route in the

King County Metro King County Metro, officially the King County Metro Transit Department and often shortened to Metro, is the public transit authority of King County, Washington, which includes the city of Seattle. It is the eighth-largest transit bus agency in t ...

system. The E Line debuted in 2014, replacing Route 358—itself the successor to Route 359, which was retired in 1999 after a Metro bus was involved in a shooting and crashed off the Aurora Bridge. The E Line terminates in Downtown Seattle and near the county line at the Aurora Village Transit Center, where

Community Transit Community Transit (CT) is the public transit authority of Snohomish County, Washington, United States, in the Seattle metropolitan area. It operates Public transport bus service, local bus, paratransit and vanpool service within Snohomish Count ...

's route 101 and Swift Blue Line begins. Swift features off-board fare payment and longer spacing between stops, and runs from Shoreline to Everett Station via Evergreen Way. The Everett Mall Way section of SR 99 is served by Everett Transit route 7, which connects the Everett Mall to Downtown Everett and Everett Station.

Major intersections

References

External links

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Highways of Washington StateSR 99 Alaskan Way Viaduct Replacement Program
{{DEFAULTSORT:Washington State Route 099 State highways in Washington (state), 099 Transportation in Pierce County, Washington Transportation in King County, Washington Transportation in Snohomish County, Washington Seattle metropolitan area U.S. Route 99