Planned maintenance on the Vector Pipeline starting Monday and continuing into next week could restrict up to 1 Bcf/d or more of volumes normally bound for eastern Michigan and the Dawn Hub in Ontario, Canada.

Vector, which posted notice of the maintenance in February, said the work is needed to prepare its system to interconnect with the Rover Pipeline, which is currently under construction. Vector is also making modifications to its Milford Junction Interconnection related to DTE Gas Co. and the Nexus Gas Transmission pipeline, as well as enhancing its Union Gas Dawn Interconnection.

“Each of the projects entails a full cutout of mainline piping, necessitating complete depressurization of certain segments at specific times,” Vector told shippers via its electronic bulletin board.

For Phase 1, lasting through next Monday, multiple receipt points will be unavailable, with others “highly limited.” Vector said it will be limited during Phase 1 to gas received at the Joliet Compressor Station in Illinois and delivered as far east as the Jackson Interconnection at Milepost 217.4 in south central Michigan.

Natural gas analytics firm Genscape said Vector flows into the Dawn Hub have averaged 1.15 Bcf/d since the start of April.

The restriction appeared to put upward pressure on Dawn pricing for Monday’s flow date, according to NGI’s Daily Gas Price Index. Gas delivered just over the border to Dawn gained 8 cents to average $3.26/MMBtu, rising against a Midwest Regional Average that lost a penny on the day to finish at $2.96. Dawn shed five cents in Monday’s trading, with gas delivered Tuesday averaging $3.21.

“Vector receives the majority of its gas from Alliance at the Joliet Compressor Station, with the remainder made up between Northern Border [NBPL] and Guardian,” Genscape said. “There is very little gas demand between Joliet and Jackson; consequently, usual flows onto Vector will likely be displaced elsewhere.”

Genscape natural gas analyst Vanessa Witte told NGI that nominations into Vector from Alliance and NBPL decreased sharply Monday. Gas from Alliance was primarily rerouted onto ANR (increasing from around 400,000 MMBtu to 800,000 MMBtu day/day), while NBPL flows into Illinois dropped from around 866,000 MMBtu to 480,000 MMBtu, according to Witte.

NBPL appeared to increase deliveries to Northern Natural upstream of the Joliet Hub, she said.

Witte said she expects reduced injections into Dawn storage to compensate during the Vector maintenance.

AccuWeather forecasts for Toronto this week show temperatures hovering around the 40s to mid-50s.

“Union still has a decent amount of available import capacity that they are not using…so it’s unlikely that they are hurting for gas,” she said. “As well, average temperatures should be around mid to high 40s in Ontario over the next week, which is typical for this time of year.”

Phase 2 for the Vector maintenance is scheduled to begin next week and last through approximately May 18. For the second phase, Vector said the Union Gas Dawn interconnection will be highly limited but that it “will attempt to confirm some level of restricted nominations during the Phase 2 outage period. This level cannot be determined until the actual outage begins due to a multitude of factors.

“All interconnections except Union Gas Dawn will be available during the Phase 2 outage, leaving shippers a variety of delivery options through this time period.”

The Vector maintenance comes as the 3.25 Bcf/d Rover Pipeline, scheduled to begin service later this year, is poised to reshape Midwest markets by opening up a major new westbound artery for Utica and southwest Marcellus shale gas. Roughly 32% of Rover’s capacity will be bound for Vector via an interconnection in Livingston County, MI.

According to a recent progress update submitted to FERC, Rover had already begun pipe laying and welding work as of the first week of April.

Genscape, which has conducted multiple flyovers to assess the project’s construction, said last week that “trenching, welding and lowering of pipe into the trench is clearly underway, but large tracts of right of way are still not under active construction and a large amount remains to be done” before its target partial in-service date in July.