15.265 - SR 99 Bore Tunnel Response

Effective Date: 07/29/19

This SR 99 Bore Tunnel Response Plan was developed by the Seattle Police Department (SPD), the Seattle Fire Department (SFD), and the Washington State Department of Transportation (WSDOT). It is meant to provide guidance in the event there is a traffic incident in the tunnel (collision, disabled vehicle, etc.).

The new SR 99 Bore Tunnel is a limited access roadway that replaces the Alaskan Way Viaduct as an alternate north/south route through Seattle. It is a bored road tunnel that is approximately 2 miles long and travels approximately 250 feet under ground at its lowest point. It is a double-decker highway with two lanes in each direction and an 8-foot west shoulder and a 2-foot east shoulder.

The northbound lanes are below the southbound lanes. There are only 4 entry points for vehicles to access the tunnel:

- northbound and southbound portals at S. Royal Brougham St.

- northbound and southbound portals at Harrison St (approx).

More information on the SR 99 Tunnel and its safety features can be found on WSDOT’s website.

15.265-POL-1 Definitions

1. With Flow Entry – Responding police vehicles will enter the bore tunnel to an incident with the normal flow of traffic in the lanes affected by the incident. For example, a disabled vehicle in the northbound bore will have responding units enter the northbound tunnel with the traffic flow.

2. Opposite Direction Entry – Responding police vehicles will respond above or below the incident via the opposite direction roadway, but with the flow of that traffic for that portal. They will access the scene on foot via the emergency exit pedestrian corridors. For example, officers responding to a crash in the northbound bore will most likely not be able to get to the crash entering the northbound portal, With Flow. Instead, they will have to enter the southbound portal, stop at the location provided by dispatch and walk down the emergency egress corridor to the northbound lanes.

3. Wrong Way Entry – Due to certain emergent circumstances, responding officers and SFD personnel will have to enter the bore tunnel the wrong way, against oncoming traffic, to access the incident. However, Wrong Way Entry will not be made until a firefighter or police officer has made access to the scene utilizing the opposite direction entry and has visually verified that no vehicles can get through the incident and that all vehicles beyond the incident are clear from the tunnel.

Note: Simple visual confirmation by WSDOT’s Traffic Management Center (TMC) camera’s DOES NOT constitute verification that all is clear. It is imperative that a Seattle police officer or Seattle firefighter, in conjunction with WSDOT’s TMC cameras, physically confirm that there is a physical barrier halting traffic and that no traffic is still in the roadway downstream from the incident prior to any police or fire vehicles entering the tunnel the wrong way.

4. Standby Locations – There are two designated standby locations for units awaiting deployment into the tunnel for a Wrong Way Entry:

- South Portal Standby Location (for NB travel) – 1st Ave. S. and S. Royal Brougham Way

- North Portal Standby Location (for SB travel) – 6th Ave. N. between Harrison St. and Mercer St.

5. Fire Zone – The SR 99 Bore Tunnel has been divided into 109 Fire Zones, which are marked on the walls of the tunnel. The Fire Zones are stacked so that, whether the incident occurs in the northbound lanes or southbound lanes, the Fire Zones remain the same, either above or below each other.

6. Emergency Doors / Egress Doors – There are 16 Emergency/Egress doors in the tunnel that allow access into the emergency pedestrian corridors. These doors are located every 650 feet and the lead to emergency escape refuge areas that lead to the north and south portals. Again, the Emergency Doors are clearly numbered and are stacked so that they are in the same location whether they are in the northbound lanes or southbound lanes.

7. Deluge System – The SR 99 Bore Tunnel is equipped with a water deluge system in the event of a fire in the tunnel. It is an automatic detection and activation system that can be manually overridden by the TMC. It only releases water, not foam or any other chemicals. However, the amount of water released creates poor visibility and may cause standing water of up to 6 inches on the roadway.

Warning: Officers should not walk under or through the deluge system while it is activated.

8. Ventilation System – The SR 99 Bore Tunnel is equipped with a combination positive and negative pressure ventilation system that extracts smoke through louvers located in each Fire Zone. In the event of a fire, there are 8 fans capable of extracting smoke along with positive pressure jet fans forcing smoke into the louvers and out of the tunnel.

9. WSDOT Incident Response Team (IRT) – WSDOT will have staffed trucks that can assist with temporary traffic control, signage or incident mitigation. They are dedicated to the tunnel during commuting hours but are not 24/7.

10. SDOT Serious Incident Response Teams (SIRT) – City-owned emergency response vehicles staffed similarly to WSDOT IRT that will provide assistance with incidents in the tunnel during off-hours or at the request of an SPD Commander.

11. Traffic Management Center (TMC) - The WSDOT statewide roadway management center located in Shoreline on Dayton Ave. N. They operate 24/7.

12. SDOT Traffic Operations Center (TOC) – Located on the 37th floor of Seattle Municipal Tower. They manage all traffic incidents on our surface streets and can assist in the SR 99 Bore Tunnel.

13. North Operations Building (NOB) – Located at 330 – 6th Ave. N. It is the SPD/SFD designated Unified Command Post for appropriate incidents. It contains the “Operations Center” on the second floor, which contains CCTV monitors of the tunnel cameras and a direct line to the TMC. It also has the North Portal pedestrian exit from the emergency exit corridors. The NOB is the primary location for Unified Command.

14. South Operations Building (SOB) – Located at 90 – S. Dearborn St. It also has the South Portal pedestrian exit from the emergency exit corridors. The SOB will act as a secondary Unified Command Center in the event the NOB is somehow unavailable.

15. Headhouse – Street level exiting location for people exiting the lower roadways. There is one headhouse at the NOB, SW corner of the building and one at the SOB across Alaskan Way S. on the west side.

15.265-POL-2 General Policy

1. The Seattle Police Department is the Primary Responding Agency to Non-Fire or Non-Medical Emergency Incidents in the SR 99 Bore Tunnel

Both the WSDOT incident Response Team (IRT) and SDOT’s Serious Incident Response Team (SIRT) shall be utilized, when available, to assist with:

- Temporary Traffic Control

- Tunnel Signage

- Incident Mitigation

Note: Both WSDOT IRT and SDOT SIRT trucks have the capability to push vehicles out of the road way to clear traffic lanes, per TIM’s protocols, and shall be utilized as such whenever possible.

2. The Seattle Fire Department is the Primary Responding Agency to Fire or Medical Emergency Incidents in the SR 99 Bore Tunnel

Seattle Fire will respond under their Standard Operating Guideline for SR 99 Tunnel

3. The Washington State Department of Transportation Traffic Management Center Monitors and Maintains Primary Facilities Control of the SR 99 Bore Tunnel

Each of the following may be called upon to assist WSDOT for Variable Message signage activations and/or confirmation they are working.

- Seattle Police & Fire Operations Personnel


- Seattle Police Dispatch

- Seattle Fire Dispatch


15.265-POL-3 Types of Responses

1. With Flow Response

The primary strategy for most incidents will be a “With Flow” approach. Deviations may be made based on information received either through the SPD Communications Section or the Seattle Fire Alarm Center (FAC).

Officers will respond to an incident and determine the best course of action, keeping in mind that the objective is life safety first, then clearing the roadway as quickly as possible. If there are no injuries and the vehicles are drivable, direct the involved parties to a safe location (Steer It and Clear It) where they can either exchange information or a report can be taken. If it is a call of a disabled vehicle, call for a private tow (if it already hasn’t been done) and see if WSDOT IRT can respond to push the vehicle out of the tunnel to a safe location.

If officers cannot access the scene due to congestion and traffic is at a stand-still, the officer should request an Opposite Direction Entry from another unit to enter the tunnel from the opposite direction and travel up or down the stairway to the incident based on the Fire Zone or Egress Door location provided on the call and check for injuries and report on the status of the incident.

Note: SPD Communications dispatchers may have already dispatched as an Opposite Direction Entry based on 9-1-1 calls, reports from the TMC from camera views of the incident or from SFD’s Fire FAC. A unit should still respond With Flow to mitigate any congestion upstream from the incident.

2. Opposite Direction Response

If With Flow is not possible, respond from the opposite direction and travel up or down one level to access the incident based on the Fire Zone number and/or the Emergency/Egress Door number. Park on the 8-foot shoulder for safety reasons.

If SFD is also responding to an Opposite Direction Response, keep in mind that they may already be on scene and may be occupying the 8-foot shoulder plus one lane of travel. Their objective is to leave one lane of travel open for a transportation corridor or apparatus access.

Irrespective of whether SFD is on scene or not, always assess the scene prior to entering the roadway that the incident is on. If it is not safe to access the scene, request additional units to respond utilizing the Opposite Direction Response. Units should also be dispatched to a With Flow response to be able to stop traffic from entering the incident scene or to access the scene itself. Officers should provide continual updates via radio as to arrival, access locations, incident location, traffic or lane clearance or movement, or where units may be needed to make the scene safe.

3. Wrong Way Entry

There are only three instances where SFD will start an automatic response to a Wrong Way Entry and will dispatch units to the standby location in addition to dispatching Fire Units to an Opposite Direction Response:

- Major Fire

- Rescue Extrication

- Hazmat

In those three instances, SPD Dispatchers should also dispatch units to the standby location to meet SFD, as well as dispatching units to an Opposite Direction Entry and a With Flow Entry. Units responding to the standby location shall not enter the tunnel, that the incident is in, the wrong way until they receive confirmation it is safe to do so either by SPD Communications, another SPD Unit that has “eyes on” the actual incident and can verify that it is safe to enter or by an SFD Firefighter/Chief that has “eyes on” the scene and can verify that it is safe to enter the wrong way and against the normal flow of traffic. SPD will then proceed cautiously and escort the SFD Units at the standby location.

SPD Communications Dispatchers will still dispatch units With Flow in order to clear out the tunnel upstream from the incident and to open up additional lanes of traffic for more SFD Units, if needed.

SPD Communications Dispatchers will also dispatch units to respond from the Opposite Direction to be able to accompany the SFD Units also responding from the Opposite Direction and to travel up or down to the scene to assess the incident and report back.

Note: No SPD personnel will enter the scene of a hazmat spill until the Seattle Fire Department has rendered it safe to enter. The TMC has the capability to view the scene via their tunnel cameras and can provide visual updates to responding personnel.

In the event of a Wrong Way Entry response, the Seattle Police Communications Dispatcher will also dispatch a Supervisor to the scene and dispatch a Lieutenant to the NOB to be part of Unified Command.

4. Role of the TMC

WSDOT’s Traffic Management Center will be monitoring all incidents in the tunnel. They have the ability to isolate the incident utilizing their cameras and can provide information to both SFD and SPD personnel responding to the incident. They can also manually override any system in the tunnel and extend any existing safety protocols (Deluge System and Ventilation System).

The SR 99 Bore Tunnel has three different types of fans to keep fresh air flowing in the tunnel and remove fumes from engines or fires. Under normal operations, vehicles traveling through the tunnel act like pistons, pushing fresh air into and through the tunnel. When environmental monitoring stations inside the tunnel detect increasing particulates in the air, jet fans automatically activate and supplement the air flow. In the event of a vehicle fire, the tunnel’s eight large extraction fans pull smoke out via vents in the tunnel wall while the jet fans push fresh air inside. The extraction fans push the smoke out the tunnel’s yellow ventilation stacks, located atop the operations buildings at both ends the tunnel. The TMC can also override the automatic sensors and activate the ventilation system.

Each emergency door leads to a refuge area/exit. The enclosed emergency walkways have an independent ventilation and fire control system. The pedestrian refuge areas have concrete walls and fire-resistant doors that separate it from the tunnel’s road way. Pedestrians can either shelter-in-place in the refuge areas or make their way to the exits at either the NOB or SOB. Responding SPD officers shall verify that there are no victims in the refuge areas prior to clearing the scene.

The TMC will activate overhead dynamic messaging signs in the tunnel and broadcast emergency instructions over loudspeakers in the tunnel to direct drivers and pedestrians in the event of an incident in the tunnel.

There are emergency push-to-talk phones inside the tunnel that connect directly to the Seattle Police Communications Section, if needed.

The TMC will also activate their overhead lane closure signs to warn drivers that a lane is closed or both lanes are closed. They will also activate their dynamic messaging signs upstream from the incident to warn drivers that the tunnel is closed. At the request of the Seattle Police Department, the TMC can also drop the roadway gates preventing cars from entering the tunnel.

15.265-POL-4 Responsibilities of the Communications Section

1. The Communications Section will Refer to Their Internal Manual

The Seattle Police Communications Center responses to incidents in the SR 99 Bore Tunnel have been outlined in their internal Policies and Procedures Manual under Section 5.201 – SR 99 Tunnel Responses.

Officers are reminded that the chief of police gives Communications dispatchers the authority and responsibility to manage field unit resources.

15.265-POL-5 Responsibilities of the Primary and Secondary Officers

1. Officer Responding to Minor Blocking Collisions, with no Injury Reported, or Disabled Vehicles will Respond to the Incident With Flow

Upon arriving, if possible, officers will attempt to clear the roadway as soon as possible utilizing either WDSOT IRT or SDOT SIRT.

If neither are available, then a tow should be called as soon as practical to clear the roadway.

There are “landing areas” just outside each portal entrance where vehicles can be pushed to clear the roadway while the vehicle owner is awaiting a private tow.

Officers will complete the necessary paperwork or clear the call with a “union” if no paper is written.

Whenever the roadway is blocked, once the roadway is clear, update that on CAD. If both lanes are blocked and one lane is able to get open, please note that time also.

2. Officers Responding to Unknown Injury Collisions or Other Incidents Involving Complete Lane Closures in One Direction will Respond Both With Flow and an Opposite Direction Entry

The units responding to the incident With Flow will assess the traffic flow and determine if re-routes need to be implemented to prevent additional vehicles from entering the tunnel.

The units responding with the Opposite Direction Entry will approach the scene from the tunnel either above or below the incident and will access the incident by traveling on foot through the pedestrian corridors.

An SPD supervisor will also be dispatched to any call involving an Opposite Entry Response.

SPD Communications will provide all responding personnel with the direction that the incident is in, the Fire Zone Number and Egress Door number.

Note: The numbers are the same whether the incident is in the northbound or southbound tunnel.

The units responding via the Opposite Direction Entry will most likely be the first units on scene and can update the call accordingly.

Seattle Fire will also be responding to most injury collisions with the Opposite Direction Entry and will stage their rigs either above or below the incident and then proceed on foot to the scene with limited equipment to administer aid or fight any fires.

Seattle Fire has primary control of any Aid or Fire scenes; SPD will assist as needed with traffic mitigation.

The SPD Supervisor will contact the Seattle Fire Incident Commander and will coordinate police resources and assist Seattle Fire, as needed.

Once SFD clears the scene, SPD will take the lead and will attempt to clear the vehicles as soon as possible and investigate the incident.

Updates to the Communications Section need to be broadcasted with anticipated roadway closure durations or when a traffic lane can be open.

If a TCIS response is required, SPD will shut down the tunnel in the direction of travel the incident has occurred, from the appropriate portal, until TCIS has cleared the scene.

Notify a patrol or traffic supervisor in the event the closure will go for an extended period beyond one hour in duration.

Once the incident is clear and traffic operations return to normal, note the time via a CAD entry.

3. Officers Dispatched to a Major Incident in the Tunnel will be Dispatched With Flow, Opposite Direction Entry and will Be Sent to the Stand By Location to Prepare for a Wrong Way Entry Response with Seattle Fire

Wrong Way Entry Responses will automatically be dispatched for the following three circumstances:

- Major Fire

- Rescue Extrication

- Hazmat Situation

Wrong Way Entry Responses will also automatically trigger a Unified Command Response involving SPD, SFD, WSDOT and SDOT and the Command Center in the North Operations Building (NOB) will be activated and staffed.

An on-duty Lieutenant will be dispatched to the NOB as the police representative for Unified Command.

Officers sent to the Stand By location will not enter the tunnel the wrong way until they received confirmation form a unit at the scene that it is safe to do so.

Once authorized to affect the Wrong Way Entry, officers will respond cautiously entering the tunnel against oncoming traffic and escort the Seattle Fire Department Vehicles to the scene.

Once arrived at the scene, SFD will continue to have Incident Command of the scene until they release the scene to SPD. Officers will assist the SFD On-Scene Incident Commander until Unified Command is established and direction is conveyed through the Command Center.

Once Unified Command has been established in the Command Center in the NOB, all police activity will be controlled by the Police Incident Commander in the NOB.

After the scene has been stabilized and Seattle Fire has turned over command to the Police Incident Commander in the Command Center, officers will investigate the incident as directed.

Upon clearing the scene, the Unified Command will be demobilized and the on-scene SPD supervisor will ensure that any necessary investigative steps are completed.

15.265-POL-6 Responsibilities of the Responding Sergeant

1. A Seattle Police Supervisor will Respond to all Scenes Involving an Opposite Direction Response

The sergeant will contact the on-scene Seattle Fire Commander and assist with coordinating police activities to mitigate traffic issues and to help Seattle Fire in looking for additional victims or scene control.

Once Seattle Fire has contained the scene and turned it over to the Seattle Police, the sergeant will coordinate police activity with the goal of:

- Restoring normal, safe traffic flow as quickly as possible and relaying any anticipated delays to the Communications Section.

- Establishing traffic reroutes for incidents that have extended tunnel lane closures.

- Clearing all police resources out of the scene as soon as practical.

15.265-POL-7 Responsibilities of the Responding Lieutenant (Unified Command)

1. A Seattle Police Lieutenant will Be Dispatched to Major Incidents in the Tunnel Requiring a Wrong Way Entry Response

The lieutenant will respond to the Command Center in WSDOT’s North Operations Building (NOB), 333 – 6th Avenue N. on the second floor. After hours, request a WSDOT SR 99 Tunnel Engineer to respond and activate the NOB.

The lieutenant will assume his or her role as part of Unified Command involving Seattle Fire, Seattle Police, WSDOT and SDOT.

Seattle Fire will have overall scene command until the incident has been stabilized.

Once Seattle Fire stabilizes the scene, Seattle Police will take over Unified Command until the scene is clear.

Once we clear the scene, Unified Command will officially be turned over to WSDOT so that they can conduct infrastructure checks on the tunnel to ensure it is safe for use.

The lieutenant will ensure that all appropriate documentation is completed and forwarded accordingly.


Adrian Diaz, Chief of Police
Address: 610 5th Avenue, Seattle, WA, 98104-1900
Mailing Address: PO Box 34986, Seattle, WA, 98124-4986
Phone: (206) 625-5011
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