October 26, 2010 - funding for dam rebuilding to maintain lake levels?

Fall foliage in the Basin, Phippsburg, above an old tide mill site.

In the past, I've looked at issues relating to dams and the water level of their ponds and impoundments.  For example, in March 2010, dam repair issues on Cobbosseecontee Stream resulted in a drawdown of Pleasant Pond by a foot or so.  Then again, in September 2010, owners considered further dam repair on the Cobbosseecontee that would affect lake levels and users.

Today, a news item from Canton, Maine.  A committee is exploring grant funding to rebuild a dam on Whitney Brook that maintains the water level in Lake Anasagunticook in Canton and Hartford.

The Dam Advisory Committee is now seeking funding to conduct an archeological survey in order to obtain a Community Block Development Grant.  Currently, the old bridge piers remain in the river, while a temporary dam is in place.  If the project is developed, the site will also feature both a boat launching site and a park.

Lake Anasagunticook's water level, and the steps taken to maintain that level, have been the subjects of some contention in recent years.  This 10/30/2009 Kleinschmidt report describes the recent history of the situation:

Several dam safety issues with the existing structure and embankments were identified by the Maine Emergency Management Agency (MEMA) during a dam safety inspection by MBP Consulting in August 1997. Subsequent to issuance of the dam inspection report, MEMA issued a Dam Safety Order to undertake remedial actions to address the dam safety issues. The former dam owner did not comply with this order, dated December 4, 2006. On May 8, 2007, a Supplemental Dam Safety Order was issued by MEMA ordering that the four gates be left open until such time that an acceptable remedial action plan is implemented. Since that date, the gates have been open, thereby reducing the water level in Anasagunticook Lake by approximately 6-feet. The Town of Canton acquired the Anasagunticook Lake Dam through an eminent domain proceeding in 2008.

It will be interesting to see what happens on the lake, and what funding sources are available to support any development.  Even for a project without any energy-related tax credits or incentives, Community Block Development Grants and other federal funding sources may be available for a dam rebuilding project to maintain lake levels.

September 10, 2010 - Cobbossee dam repairs

Dam repairs pose interesting technical, environmental, and social challenges.  The situation with the Cobbossee Outlet Dam, in the town of Manchester, Maine, provides a good example.

For your reference, here is a Google map of the dam site.  This is several miles farther upstream from the New Mills Dam in Gardiner, which had its own dam repair and drawdown issues this spring.

The Town of Manchester owns the dam, which maintains the water levels in 5,000-acre Cobbossee Lake above, as well as ensuring adequate flows in Cobbossee Stream below the dam.  In all, parts of six municipalities are affected by the waters of Cobbossee.  The dam is damaged: one of its six gates is currently boarded up because it was at risk of failing.  Rotting wooden timbers need to be replaced, possibly with galvanized steel beams.

To perform the repairs, the lake level may have to be drawn down.  This concerns boaters on the lake, who fear that the drawdown might end the boating season early.  To address this concern, the plan is to do the dam repairs during this fall's annual seasonal drawdown of the lake.  Many dam managers perform drawdowns in the fall for flood control and to make room for spring runoff. 

Cost and cost-sharing are also at issue.  Currently, as the dam owner, Manchester appears to be on the hook for the repair costs, although there is talk of asking other communities along the watershed to pay into a repair fund.  It will be interesting to see how the project progresses.

September 3, 2010 - Elwha dam removal; Northwest Passage

Hydroelectricity: I'm continuing to follow the removal of two dams on the Elwha River in Washington.

Here is a map I created showing the two dam sites.

Here is the Bureau of Reclamation's information on sedimentation behind the Elwha River dams: nearly 18 million cubic yards of sediment behind Glines Canyon Dam and Elwha Dam.  The Bureau gives this history:

Private companies constructed two large dams on the Elwha River during the early 1900’s. Elwha Dam, constructed during the period 1910-13, is a 105-foot high concrete gravity dam that forms Lake Aldwell 8 miles upstream from the river's mouth. Glines Canyon Dam, built in 1927, is a 210-foot high concrete arch dam that forms Lake Mills 13 miles upstream from the river's mouth. When the dams were first built, they were significant producers of electricity on the Olympic Peninsula. Today, the dams are operated in a run-of-the river mode and generate about 40 percent of the electricity needs for the Diashowa America paper mill in Port Angeles, Washington.

The Bureau also has interesting information on erosion after drawdown.  As we've seen before, drawdown can be done to minimize harms but can also cause serious problems if the newly exposed slopes of the impoundment or riverbank are unstable.




Meanwhile, in Maine, a graphic example of how business climate can make a difference: an entire lumber mill, closed for the past four years, is up for sale and might be moved piece by piece to Siberia.  People often talk about how jobs move overseas; here, not only the (already lost) jobs but the workplace may move.
The situation on the Sebasticook River continues to brew after the Fort Halifax dam removal; now, town officials are considering a renewed investigation into erosion of the riverbanks after drawdown and dam breach.

An interesting bit of fisheries news: Native Americans from the Passamaquoddy Tribe continue to fish federal waters, despite being cited for lack of permits and certain mandatory safety gear during a scallop fishing trip off Nantucket.  The natives point to their indigenous fishing rights.

Arctic news: I have a special interest in the Canadian Arctic, including the fabled Northwest Passage.  Today comes news that a fuel tanker has run aground along that shipping route on a sandbar near Gjoa Haven.

September 2, 2010 - sewage digestion; dam damage

In August, news covered the plans of the Lewiston-Auburn Water Pollution Control Authority to build a anaerobic digester plant at its sewage treatment facility.  The plant would reduce the Authority's solids disposal costs and could generate significant energy from the methane produced.  Now, the Lewiston Sun Journal says they're clarifying that it is "not a given" that the Authority will develop the project.

Hydroelectricity: a rock has fallen onto the Ennis Dam on the Madison River in Montana.  Here is a map of the Ennis Lake and gorge area.  You can see pictures here and a map here.  It looks like Ennis Lake will be drawn down 5' to relieve some of the back-pressure on the dam, and then later draw it down another 4' for a full inspection and possible repairs.  Ennis Lake only averages 8'-9' deep, so this drawdown will have noticeable effects -- if not as permanent as the effects of drawdown prior to breach.  Hopefully the drawdown will not cause landslides and erosion as at Fort Halifax on the Kennebec River in Maine.

What's it like behind the gates of Bath Iron Works?  This Working Waterfront piece gives a good description of a tour of the large defense contractor on the Kennebec River.

June 15,2010 - Maine dam removal: Lower Montsweag Brook Dam

Two Maine dam removal projects recently won funding from nonprofit conservation organization American Rivers and the U.S. Commerce Department’s National Oceanic and Atmospheric Administration Restoration Program. The Maine Council of the Atlantic Salmon Federation won $65,000 to remove the West Winterport Dam on Marsh Stream, a Penobscot River tributary, in Winterport and Frankfort, which will open up 4.5 miles of the stream and restore 20 miles of river habitat.

The other grant was $100,000 to the Chewonki Foundation for the removal of the Lower Montsweag Brook Dam near Wiscasset and Woolwich. This removal will reopen three miles of fish passage and restore the 20 acres of riverine habitat currently flooded by the dam.

Lower Montsweag Brook Dam (map) was constructed by Maine Yankee Atomic Power Company in 1968. The purpose of the 30' tall dam was to impound a backup supply of emergency water for Maine Yankee's nuclear power plant operations.

Chewonki acquired the dam as part of the 2008 Natural Resources Damages Restoration Plan and Settlement Agreement (NRDAR) between Maine Yankee and the State of Maine. As part of that settlement, Chewonki committed to evaluate alternatives for restoring fish passage and riparian habitat in the lower brook.

A feasibility study by Stantec Consulting, Inc., of Topsham, showed that removal of the concrete dam is the most effective and least expensive way to restore fish passage for fish species such as river herring, rainbow smelt, brook trout, and American eel.

Chewonki plans to remove the dam later this summer at a cost of $750,000 to $800,000. A slow drawdown of the impoundment was scheduled to begin in May. This drawdown will allow contractors to inspect the upstream face of the dam and to begin revegetating the impoundment area. Demolition activities will be scheduled to coincide with the low stream flow period of late summer.

June 7, 2010 - update: Fort Halifax dam removal and erosion

A Morning Sentinel article today describes how the Maine Department of Environmental Protection is requiring FPL Energy Maine Hydro, the company that removed its Fort Halifax dam in July 2008, to stabilize the riverbank beneath the Fort Hill cemetery.

After years of legal battles, FPL removed the Fort Halifax dam from the mouth of the Sebasticook River in Winslow, Maine. As a condition of its dam removal permit, FPL was required to "closely monitor the slope adjacent to the cemetery and promptly remediate any slumping or erosion" in order "to protect the Fort Hill Cemetery from irreparable harm." Back in April, the riverbank suffered after another major landslides. FPL commissioned a study by Findlay Engineering Inc. of Yarmouth, which concluded that heavy rains and a small earthquake 41 miles away were contributing factors, but largely absolved FPL of responsibility.

Today, the news breaks that the Maine DEP is challenging FPL's study. DEP points to soil loss during the dewatering process, and a resulting lack of work by FPL to re-stabilize the slope after drawdown.

4/28/10: dam repair and communications; from wood mill to energy plant

Dam news: repairs to the New Mills Dam in Gardiner, Maine. In order to repair two uprights on the New Mills Dam in Gardiner, the Cobbossee Watershed District has drawn down Cobbosseecontee Stream and attached Pleasant Pond by almost a vertical foot, exposing more pond and stream bottom than in the past six years. The two wooden uprights of the dam were damaged by high water and bashed by ice in late February. Kruger Energy, which also operates a hydroelectric dam downstream that it acquired last November from Ridgewood Maine Hydro Partners LP, is performing the repairs, which are expected to take one day.

The New Mills Dam demonstrates one relatively common form of small dam ownership in New England. In this case, the dam is owned by the municipalities of Gardiner, Litchfield and Richmond. These three owners pay for the upkeep, while Kruger Energy is contracted out to manage maintenance and repairs.

Here, the drawdown has concerned some people who live along the impoundment. They are concerned about erosion, nesting ducks, fish, and in general about the management of the impoundment. While the drawdown is required for safety during the dam repairs, this situation demonstrates the importance of communication and collaboration between dam owners and neighboring abutters.



From a forest products mill to an energy facility! The town of Madison is considering the potential transformation of the former Anson Stick Mill into an energy-producing facility. The town acquired the abandoned mill and its biomass boiler from Downeast Woodcrafters, and now is exploring creating a municipal heating district within the downtown area. While municipal heating districts are common in Europe, as well as on American institutional campuses (e.g. universities), the practice is not widely deployed in New England. Madison Economic Development Director Joy Hikel said the goal behind a potential energy-producing facility is twofold: to reduce heating or electricity costs for the owners of the downtown buildings by 40 to 50 percent, and to provide local utility Madison Electric Works with an affordable source of energy to sell to consumers.