TSP Name: Northwest Pipeline LLC TSP: 67977322
Critical: Y
Notice Stat Desc: SUPERSEDE
Notice Type Desc: MAINTENANCE
Post D/T: 09/08/2025 1:27 PM MCT
Notice Eff D/T: 09/08/2025 1:27 PM MCT
Notice End D/T:
Reqrd Rsp Desc: No response required
Rsp D/T:
Notice ID: 25-144
Prior Notice: 25-139
Subject: Additional Unplanned Maintenance at Chehalis CS
Notice Text:
Northwest has experienced a mechanical issue at the Chehalis
Compressor Station, resulting in both Units 1 and 2 being
offline.
Effective Gas Day Tuesday, September 09, 2025, and until
further notice, the available capacity through the Chehalis CS
will be 500,000 Dth/d Southbound.
Northwest will continue to mitigate Operational Flow Orders
(OFO) and deficiency impacts at the Chehalis compressor station
on an operationally available basis, as referenced in Notice ID
25-139 and 25-140. Any changes or updates to the schedule will
be promptly communicated via the Northwest Pipeline Portal.
If the southbound scheduled quantities exceed Northwest’s
design capacity of 672,000 Dth/d at Chehalis Northwest will
provide Shippers with their specific OFO obligations by 4:00
p.m. MST. Shippers must comply with their OFO obligations no
later than the Evening nomination deadline (5:00 p.m. MST).
If an OFO is necessary for a given Gas Day, Northwest will wait
until the Evening scheduling process to provide notice of a
Declared Deficiency period and will make deficiency cuts to
bring the nomination requests at the Chehalis compressor from
the design capacity of 672,000 Dth/d to the operationally
available capacity of 500,000 Dth/d (or whatever NWP cannot
mitigate during any day of the unplanned maintenance period),
all pursuant to Sections 10.2 and 10.3 of Rate Schedule TF-1 in
Northwest's Tariff. The deficiency period will continue until
the work is completed.
Northwest Pipeline sincerely apologizes for this additional
disruption and is working diligently to safely bring this
station back into service as quickly as possible to minimize
any impacts.
Shippers can monitor throughput quantities and obtain a copy of
Northwest’s OFO procedures on Northwest’s website at
www.northwest.williams.com.
If you have any questions, please contact your Commercial
Services Representative or the hotline at 713-215-6301.