Maintenance Construction Schedule - MountainWest Pipeline

2026 Schedule

Period Category Preliminary Dates Duration Location Project Possible Customer Impact Current Capacity (Dth/d) Restricted Capacity (Dth/d) Anticipated Firm Cut Quantity Anticipated Total Nomination Cut %
March - April Reservoir Testing March 27 - April 7 13 Days Clay Basin  Annual Withdawal Test No physical injections allowed starting GD March 27 through GD March 30.
GD March 30, constant 325 MMcf/day WD rate. 
GD March 31, constant 350 MMcf/day WD rate.
GD April 1 through GD April 7, reservoir shut-in
Resume normal operations GD April 8.
Varies, See latest EBB Mar 30 Withdraw: 341,250 Dth/d 
Mar 31 Withdraw: 367,500 Dth/d
 Apr 1- Apr 7: 0 Dth/d
ALL 100%
April Pig

April 1

1 Day

JL46
Smart Tool

None
N/A
N/A 0 Dth/d 0%

April

Pig

April 2

1 Day
ML 40 Pete's Wash to Fidlar

Smart Tool
None N/A N/A 0 Dth/d 0%
May Anomaly Digs  April 6 - May 9 33 Days JL46/JL47 Anomaly digs Reduced Flows on JL46 Myton and JL47 Myton Segments
JL 46 Myton: 66,200 Dth/d
JL 47 Myton: 77,700 Dth/d
TBD TBD TBD

April

Pig

April 7 - 9

3 Days
ML 13 Nightingale to Eakin

Smart Tool
None N/A N/A 0 Dth/d 0%

April

Pig

April 9

1 Day
ML 1 Nightingale to Eakin

Smart Tool
None N/A N/A 0 Dth/d 0%
April Compressor Maintenance April 20 - 24 5 days Oak Springs Compressor Station Station ESD Testing Capacity reduction on ML 104 Goshen Segment of 120,000 Dth/d ML 104 Goshen: 384,500 Dth/d ML 104 Goshen: 264,500 Dth/d TBD TBD
April
Compressor Maintenance April 27- May 1 5 Days Simon Compressor Station Station ESD Testing Capacity reduction on ML22 to Nightingale Segment of 27,650 Dth/d. 
Increased ML22 pressures for Vermillion Plant MAP 293, Skull Creek Delivery MAP 167, Skull Creek Receipt MAP 967
Nightingale ML22 Segment: 206,650 Dth/d  Nightingale ML 22: 179,000 Dth/d 0 Dth/d 0%
May

Pig

May 5 - 6

2 Days
ML 2 Coalville to Little Mountain

Smart Tool
None N/A N/A 0 Dth/d 0%
May

Pig

May 7

1 Day
ML 14 Coalville to Little Mountain

Smart Tool
None N/A N/A 0 Dth/d 0%
May Compressor Maintenance May 12 - 13 2 Days Kanda Compressor Station Station ESD Testing All Compression Offline
Kanda/Col CIG DEL MAP 171 shut in
Kanda/Col CIG REC MAP 871 shut in
Kanda/Col CIG DEL MAP 171: 178,000 Dth/d Kanda/Col CIG REC MAP 871:138,000 Dth/d
Kanda/Col CIG DEL MAP 171: 0 Dth/d 
Kanda/Col CIG REC MAP 871:0 Dth/d
ALL 100%
May

Pig

May 13 - 14

2 Days
ML 13 Nightingale to Eakin

Smart Tool
None N/A N/A 0 Dth/d 0%
May

Pig

May 18 - 19

2 Days
ML 13 Nightingale to Eakin

Smart Tool
None N/A N/A 0 Dth/d 0%
May Compressor Maintenance May 18 - 22 5 Days Leroy Compressor Station Station ESD Testing
No Injection or Withdraw at Leroy
Aquifer Storage Injection: 61,200 Dth/d
Aquifer Storage Withdraw: 134,900 Dth/d
Aquifer Storage Injection 31,200 Dth/d
 Aquifer Storage Withdraw: 74,900 Dth/d
0 Dth/d 0%
June Anomaly Digs June 1- 10 10 Days ML48/ML60 Junction Anomaly Digs Lower Operating Pressures N/A N/A 0 Dth/d 0%
June 

Pig

June 2

1 Day
ML 104 Thistle to Goshen

Smart Tool
None ML 104 Goshen Segment: 384,500 Dth/d N/A 0 Dth/d 0%
June Compressor Maintenance June 15 - 19  5 Days Thistle Creek Compressor Station  Station ESD Testing All Compression Offline
Lowered capacity on ML 104 Goshen Segment
ML 104 Goshen Segment: 384,500 Dth/d
ML 104 Goshen: 302,000 Dth/d
TBD TBD
June 

Pig

June 16 - 18

3 Days
ML 2 Coalville to Little Mountain

Smart Tool
None N/A N/A 0 Dth/d 0%
June 

Pig

June 24

1 Day
ML 14 Coalville to Little Mountain

Smart Tool
None N/A N/A 0 Dth/d 0%
July Anomaly Digs July 6- 31 28 ML 1, ML13, and ML15 from Nightingale to Eakin Anomaly Digs Taps switching lines. No impacts anticipated. No flow reduction or pressure restrictions. N/A N/A 0 Dth/d 0%
July Compressor Maintenance July 7 - 8  2 Days Coleman Compressor Station Station ESD Testing All Compression Offline Kanda/Coleman Segment: 410,000 Dth/d TBD TBD TBD
July

Pig

July 15

1 Day
ML 104 Thistle to Goshen

Smart Tool
None ML 104 Goshen Segment: 384,500 Dth/d N/A 0 Dth/d 0%
August

Pig

August 4

1 Day
ML 1 Nightingale to Eakin

Smart Tool
None N/A N/A 0 Dth/d 0%
August Anomaly Digs Aug 3- 15 13 ML22 and ML23 Skull Creek Compressor Anomaly Digs Capacity reduction on ML22 Nightengale segment, reduced pressures. Varies, See latest EBB TBD TBD TBD
August

Pig

August 6

1 Day
ML 1 Nightingale to Eakin

Smart Tool
None N/A N/A 0 Dth/d 0%
October Reservoir Testing October 4 - 17 13 Days Clay Basin Annual Injection Test No physical withdraw allowed starting GD Oct 4 through GD Oct 6. 
GD Oct 6, constant 250 MMcf/day INJ rate. 
GD oct 7, constant 275 MMcf/day INJ rate. 
GD October 8 through GD October 15, reservoir shut-in Resume normal operations GD October 16.
Varies, See latest EBB TBD ALL 100%

Note: This schedule is subject to change. It is recommended the Shippers monitor MountainWest Pipeline's critical notices about schedule revisions.