Mosquito Lake Outage Extended

TSP Name: Northwest Pipeline LLC TSP: 67977322

Critical: Y
Notice Stat Desc: SUPERSEDE
Notice Type Desc: MAINTENANCE
Post D/T: 07/09/2026 9:35 AM MCT
Notice Eff D/T: 07/09/2026 9:35 AM MCT
Notice End D/T:
Reqrd Rsp Desc: No response required
Rsp D/T:

Notice ID: 26-134
Prior Notice: 26-132
Subject: Mosquito Lake Outage Extended

Notice Text:

As posted in the maintenance schedule on Northwest Pipeline's 
website, Northwest is currently performing maintenance at the 
Sumas CS (located at MP 1484.48 in Whatcom County, Washington) 
from Gas Day July 6, 2026, through Gas Day July 10, 2026, and 
referenced in Notice ID 26-132. However, due to a delay in 
receiving the required materials, this outage has now been 
extended through Gas Day July 13, 2026. 

The Sumas CS will continue to be limited to 1,075,000 Dth/d 
southbound through the extended outage.

If primary nomination requests through the Sumas CS exceeds the 
available capacity of 1,075,000 Dth/d southbound (or whatever 
NWP cannot mitigate during any day of the maintenance), 
pursuant to Sections 10.2 and 10.3 of Rate Schedule TF-1 in 
Northwest's Tariff, Northwest will give notice of a Declared 
Deficiency Period based on a design capacity of 1,409,000 Dth/d 
southbound. The deficiency period will continue until the work 
has been completed.

Northwest Pipeline apologizes for this extended delay and is 
working diligently to safely bring this station back into 
service as quickly as possible to minimize any potential 
impacts.

Please reference the Maintenance Schedule tab at 
www.northwest.williams.com for more information.

If you have any questions, please call your Commercial Services 
Representative or the hotline at 713-215-6301.