November 10, 2010 - dam removal on Martha's Vineyard

This summer I was fortunate to spend a week on the island of Martha's Vineyard in Massachusetts.  I learned about the island's energy resources, including solar and wind on Martha's Vineyard.

Photo: wind power near the islands: Falmouth, Massachusetts.

Following up on my recent looks at dam removal, today I'm looking at some possible dam removal activity on Martha's Vineyard.  It's what you might term a large-sized island: 87.48 square miles (231.75 km²), making it the third-largest island on the east coast of the US, and the largest island on the east coast not tied to land by a bridge or tunnel.  Population-wise, the year-round population of about 15,000 residents is augmented by tourists and seasonal residents, peaking at up to 75,000 people in summer.  Still, it's a manageable size, with all points of the island relatively accessible to visitors.

It's the relatively moderate size of Martha's Vineyard that made me surprised to learn that the island is home to at least 3,000 dams.  That's about 13 dams per square kilometer, or 34 dams per square mile.  The vast majority of these dams were built in the last 200 years to provide power, water, or both to mills -- almost all of which are no longer in operation.  With no maintenance, and no ongoing operations like hydropower production, many of these dams have become overgrown, forgotten, and in poor condition.

In response to a near-disaster in 2005 when rain-induced flooding nearly broke an old dam in a densely-populated area, the Commonwealth of Massachusetts enacted new dam safety and liability laws.  These changes made it more clear that whoever owns a dam is responsible for its safety -- and for the consequences of its failure.  Many property owners did not even realize that they owned aging dams when they purchased former industrial sites, like the Briggsville Dam in Clarksburg whose owner was surprised to find itself responsible for costly repairs or removal.

When costly repairs are required to maintain state and federal licenses and certifications, dam removal is one option.  Some dams on the Vineyard still provide valuable services, like flood control or providing water supply to residents and businesses.  Others, like the Mill Pond dam in West Tisbury, impound water for scenic and recreational purposes.  Still others remain in streams, holding back small ponds, in unknown condition.  Some may be candidates for removal, while others may be candidates for powering up as small hydro-electric sites.  As an island interested in sustainability, as well as reliability, it will be interesting to see which Martha's Vineyard dams are removed, and which will be restored.

November 9, 2010 - removal of the Brantley Dam, Virginia?

Photo: a solar-powered Big Belly trash compactor seen in Salem, Massachusetts, next to a recycling bin.  Solar photovoltaic panels power this receptacle.

Today I'd like to comment on the story of the Brantley Dam on the Dan River in Danville, Virginia (about 4 hours west of Norfolk).  This older dam once provided water to the now-closed Brantley Steam Plant.  Over the years of changing ownership and possibly insufficient maintenance, the dam has recently become unpopular.  Dam safety is a major issue, with 4 deaths since 1965 attributed to the dam.

The City of Danville Public Works department has issued a report recommending that the Brantley Dam be removed.  The City is now considering removing the dam, and whether sediments trapped in the impoundment behind the dam may be toxic or polluted.  The report suggests a variety of costs for dam removal, ranging from $90,000 for a "simple removal", $110,000 for a “staged removal" - or about $307,000 to remove the dam along with the entirety of the trapped sediments.  Based on the relatively low amount of sediments, the report suggests simple removal is appropriate.

I'm curious to see what will happen with dam removal on the Dan River.  A number of other dams exist across the watershed, some of which are privately owned, and at least one of which (at a water treatment plant) is a partially breached low-head dam - picture a 30' breach in the middle of a short, curving structure.

In this case, the dam played a role in energy generation, though not through hydroelectric capacity; rather, like the Briggsville Dam in Clarksburg, Massachusetts, it was built to provide a steady supply of water for industrial processes.  In this case, the Brantley Dam supplied water to the steam plant electric generation station.  As the economy of industrial production has shifted over the past century, the underlying factory or power plant may change its operations, leaving the dam without its original purpose.  In Brantley Dam's case, the steam plant was ultimately shut down by the utility.

At some point, if the dam poses harms identified by society (safety at the Brantley Dam) without commensurate benefits, the dominant pressures may result in dam removal.  In other cases, especially where hydroelectric production is possible, if dam removal is threatened absent improved fish passage, developers may find it worthwhile to maintain the dam in compliance with the regulations.  In either case, it's a balancing act.

In Maine, last month I noted that the towns of Canton and Hartford were looking for ways to fund a dam repair project on Whitney Brook.  This dam maintains the water levels in Lake Anasagunticook.  The state had condemned the original dam, and the temporary dam needed repairs.  In today's news, the towns have announced that the Maine Outdoor Heritage Fund has awarded them a $5,000 grant for the project.  This fund is funded by designated lottery tickets, and can be used to acquire land and secure public access.  One portion of the project includes a new boat launch and park, triggering eligibility for this grant.

November 1, 2010 - Great Works dam removal?

Brilliant fall colors in the Basin, Phippsburg, Maine.

Continuing my look at dams targeted for removal: today, the Great Works dam on the Penobscot River in Maine.  This is an interesting tale of mills, dams, changes in ownership, and changes in use.  Like the Briggsville Dam in Clarksburg, Massachusetts, the Great Works dam was built to support a mill -- but like the Boston Felt dam, the Great Works dam produced renewable power.

The Great Works Hydroelectric Project (FERC project no. 2312) is located adjacent to the Old Town mill (which has changed hands over the years, and is now owned by Old Town Fuel and Fiber).  Originally built in the late 1800s, the Great Works project's FERC license was issued in 1963, with an original expiration date of March 31, 2002.

In its most recent incarnation, Great Works consisted of a powerhouse containing 11 turbine-generator units totaling about 8 MW of installed capacity; a non-overflow section with two operating fishways and three gated outlet pipes (one 6 foot square, two 9 foot diameter); and a spillway equipped with flashboards extending from the non-overflow section across the river to the east river bank in the Town of Bradley. The total length of the Project is approximately 1,353 feet. The dam forms a 128-acre impoundment at a normal impoundment elevation of 81.73 feet. The tailrace is separated from the main river by an earthen dike and the powerhouse discharges to the tailrace. The presence of the earthen dike creates a bypass reach of approximately 1,200 feet in length, and approximately 1,000 feet of which is a backwater. The project also includes two operating Denil-type fish ladders, one located in the tailrace, the other at the west end of the spillway. An older abandoned fish ladder is located near the center of the spillway.

In March 1997, James River Paper Company owned both the mill and the dam.  James River filed a notice of intent to file an application for a new license.  Shortly thereafter, the dam changed hands to PPL Great Works, LLC.  In 2003, Commission staff suspended the processing of the project's relicense application to allow negotiation of a multi-project, "basin-wide settlement agreement" - a comprehensive agreement covering water flows and dams throughout the Penobscot River watershed.

That agreement - the Lower Penobscot Basin Comprehensive Settlement Accord - ensued on June 25, 2004.  Seven conservation groups, hydroelectric company PPL Corp., the Penobscot Indian Nation and state and federal agencies, agreed to the removal of both the Great Works and Milford dams as well as the removal of flashboards and the installation of a fish bypass at the Howland Dam. 


Pursuant to the settlement agreement, on November 7, 2008, PPL Great Works and the Penobscot River Restoration Trust (Trust) filed an application to transfer the license to the Trust, and the Trust filed an application to surrender the license for the Great Works Project and remove the project’s dam.

On June 16, 2010, FERC issued its order approving the surrender of the project license (29 page PDF of the order).  In its order, FERC described the process to be used in removing the Great Works dam:

The Great Works Project impoundment would be drawn down through the opening of gates and removal of the flashboards. Then, an upstream access road would be constructed from the east bank along the entire length of the spillway. Another road would be constructed downstream out to mid-channel to allow removal of the abandoned fish ladder. The spillway would be removed in sections from west to east with concurrent removal of the access road. Following this, another road would be constructed from the west bank across the upstream side of the powerhouse. From this road, the remaining portion of the spillway immediately adjacent to the powerhouse would be removed along with the two operational fish ladders. The forebay area would be filled and graded and the access road removed. The project’s powerhouse is proposed to remain because it houses equipment for an adjacent pulp mill.

Removal of the Great Works dam may occur in 2012, bringing a close (or at least a new chapter) to this tale of a mill and its dam.  In this case, the greater Lower Penobscot Basin Comprehensive Settlement Accord and the actions of the Penobscot River Restoration Trust played a major role.  In a coming edition, I'll look at the policy considerations that went into that settlement agreement, including the promises of both improved sea-run fish passage and continued hydroelectric generation elsewhere on the Penobscot River.

October 29, 2010 - removing the Briggsville Dam

Photo: down by the West Point dock, Phippsburg.

In Clarksburg, Massachusetts, the Briggsville Dam on the North Branch of the Hoosic River is slated for removal next week.  Preliminary site work has already begun.  At 15 feet in height and 200 feet in length, the Briggsville Dam once provided cooling water to the adjacent Strong-Hewatt Mill.

Here is an interesting article on the pros and cons of removing the Briggsville dam. It's a story whose general contours will resonate with a lot of people in historic mill towns. We have a dam built in the early to mid-1900s to support a manufacturing facility. The factory changes hands several times, until a new mill owner finds it also owns the aging dam. For safety reasons (and in many places, to facilitate fish passage), the dam needs expensive upgrades -- or faces removal.

This is the story of many small dams and hydroelectric facilities across the country.  In Clarksburg, the mill was the Strong-Hewatt woolen mill.  The current owner is Cascade School Supplies Co.,who was apparently surprised to find that the building it acquired came with an aging dam.  Although fish passage will be improved by the removal of the Briggsville Dam, the primary driver of its removal are the safety issues caused by its poor condition.  Dam safety is an important issue, and without the proper capital investments in maintenance and repairs, maintaining an older dam can become an expensive liability.  (For example, see what's going on in Canton, Maine, with the Whitney Brook dam and Lake Anasagunticook.  Or what happened when the Colcord Pond dam failed this past spring.)

In this case, the Briggsville Dam appears to have been used to provide cooling water to the mill, not to generate electricity, so any policy reasons to leave it in are more clearly outweighed by the safety issues. Moreover, it will help the mill property owner avoid the costs of repairing the dam, letting Cascade stay in business at that location.

Certainly an interesting issue.  If you're near Clarksburg, swing by and take a last look at the Briggsville Dam.