The Mackinac Straits Corridor Authority voted Oct. 17 to accept a specifications-team recommendation to remove board-pile language from the joint specification for the project's permanent shaft.

Staff explained the change: the final design for the permanent south portal now uses diaphragm walls for the permanent shaft, which are covered by the joint specification section 31 56 00. Temporary portal walls will be constructed using soldier piles and lagging (board piles) for the period of construction only; those temporary piles will be removed and backfilled when construction is complete and the authority will not assume ownership of temporary portal elements.

"Because the board piles were initially envisioned to be part of the South Portal shaft permanent structure designed for the 99 year service life, therefore, they were included in the jointly developed specifications. The final design for the South Portal includes a permanent shaft to be constructed of diaphragm walls and a temporary portal shaft constructed using soldier pile and lagging walls... Therefore... the MSCA will not assume ownership of it," the presenter summarized (remarks presented on behalf of Dr. Mooney).

The chair asked for a motion to accept the recommended changes in the memorandum; a motion was made, the board voted "aye" by voice and the chair stated the recommendation had been "received and accepted." The authority recorded the action for the meeting minutes.

Why it matters: Removing board piles from the joint permanent-shaft specification narrows the authority's long-term ownership expectations and clarifies that temporary soldier-pile/lagging walls for portal construction will be constructed and removed during the construction phase.

Provenance: Staff presented the board-pile spec change beginning at 00:27:55; the motion, voice vote and acceptance occurred at 00:30:57.

Speakers: [
{"name":"Stephen Ward","role_title":"Project Manager (MDOT, on loan)","affiliation_type":"government","affiliation_name":"Michigan Department of Transportation","first_reference":{"timecode":"00:27:55","transcript_line_range":[1,12]}},
{"name":"Chair","role_title":"Chair","affiliation_type":"government","affiliation_name":"Mackinac Straits Corridor Authority","first_reference":{"timecode":"00:30:57","transcript_line_range":[1,4]}}
]

Authorities: [
{"type":"other","name":"Joint specification sections 31 56 00 and 31 63 00 (board piles)","referenced_by":["specs-board-piles-change-2025-10-17"]}
]

Topics: [
{"name":"construction_specifications","justification":"Article covers a formal change to joint construction specifications affecting permanent vs. temporary shaft treatment.","scoring":{"topic_relevance":0.95,"depth_score":0.70,"opinionatedness":0.00,"controversy":0.30,"civic_salience":0.50,"impactfulness":0.50,"geo_relevance":1.00}}
]

Provenance_segments: [
{"block_id":"1675.6849","local_start":0,"local_end":4200,"evidence_excerpt":"So on the permanent shaft, they will be there for the whole time. On the temporary shaft, those board piles that are holding the walls back so that they can do the construction will be removed and and and that land will be covered up... Therefore, the diaphragm wall construction of the permanent shaft is covered by the joint spec 31 56 0 0. The temporary portal shaft designed for the period of construction only is gonna require board piles... the MSCA will not assume ownership of it.","tc_start":"00:27:55","tc_end":"00:30:00","reason_code":"topicintro"},
{"block_id":"1856.63","local_start":0,"local_end":900,"evidence_excerpt":"I would, entertain a motion for acceptance of the recommended changes as referenced in the memorandum provided by Doctor. Michael Mooney. \n\nI move. \n\nAll in favor Aye Aye All right That recommendation has been received and accepted.","tc_start":"00:30:57","tc_end":"00:31:18","reason_code":"topicfinish"}
]