November 2, 2010 - Veazie dam removal

Tuesday, November 2, 2010

Yesterday, I looked at the Great Works Dam on the Penobscot River, and the plans to remove it.  Today, let's consider the history and fate of its sister the Veazie Dam - another dam linked by the Penobscot River Restoration Project to ultimate removal.

Photo: fall foliage near the mouth of the Kennebec River, Maine.

The Veazie Project is the lowermost project on the entire Penobscot River system.  It consists of a 902-foot-long, 25-foot-high, concrete gravity dam with inflatable rubber flashboards, a reservoir with a surface area of about 390 acres and a storage capacity of 4,800 acrefeet at a surface elevation of 34.8 feet mean-sea-level (msl), and two powerhouses on the Veazie (west) side of the river (Plant A with an installed capacity of 5.4 MW and Plant B with an installed capacity of 3 MW). A forebay located on the right side of the river feeds both powerhouses. The tailrace of Plant A is located under the concrete floor of the forebay and Plant B releases water into the river downstream of the dam. The project also includes two fish ladders: an abandoned fishway on the left bank of the river, and an operable ladder between the spillway and forebay.

As part of the comprehensive basin-wide settlement agreement between environmental advocacy organizations, state and federal agencies, and the dam owners on the Penobscot River system, the Veazie Dam is slated for removal. The Penobscot River Restoration Trust has won approval from the Federal Energy Regulatory Commission to initiate the demolition of the Veazie dam by drawing down the impoundment through the project’s gates and by deflating the flashboards.  Next, access roads would be constructed on the east bank of the Penobscot, both upstream and downstream of the dam to facilitate the demolition of the abandoned fish ladder and the east half of the spillway. Once these easterly roads are removed, the remaining portion of the spillway, powerhouse B, the operational fish ladder, the forebay, and tailrace would be removed by a west bank access road.

As the impoundments behind newly constructed dams fill with water, they often cover rivers' previous history.  Approximately 1,900 feet upstream of the Veazie Project are the submerged remnants of the historic Veazie Lumber Company Mill dam.  Because this structure is expected to significantly impair natural river flow once the Veazie dam is removed, this historic remnant is also slated for removal once the Veazie Dam is gone.

All this arises through the Lower Penobscot River Basin Comprehensive Settlement Accord.  As FERC describes it, the Settlement Accord will open a large amount of habitat to anadromous fish in the Penobscot Basin by removing the Veazie and Great Works dams and constructing a bypass around the Howland dam while retaining up to 90% of the then existing hydroelectric generating capacity within the Penobscot River area.

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