View source for Lowell Power Canal System and Pawtucket Gatehouse

{{short description|Historic district in Massachusetts, United States}}
{{distinguish|Pawtucket Falls (Massachusetts)|Pawtucket Canal}}
{{Use American English|date=January 2025}}
{{Use mdy dates|date=August 2023}}

{{main article|History of Lowell, Massachusetts}}
{{Infobox NRHP
| name =Lowell Locks and Canals Historic District
| nrhp_type = nhld
| nocat = yes
| image = 1975 map of canal system in Lowell, Massachusetts.png
| caption = A 1975 map showing the canal system
| location= [[Lowell, Massachusetts]]
| coordinates = {{coord|42|38|44|N|71|19|12|W|display=inline,title}}
| locmapin = Massachusetts#USA
| area =
| built = 1821
| architect = Nathan Appleton, Kirk Boott
| architecture =
|designated_nrhp_type = December 22, 1977
| added = August 13, 1976
| refnum = 76001972<ref name="nris">{{NRISref|2008a}}</ref>
}}

The '''Lowell Power Canal System''' is the largest power canal system in the United States, at 5.6 miles in length.  It is operating through six major canals on two levels, controlled by numerous gates.  The system was begun in the 1790s, beginning its life as a transportation canal called the [[Pawtucket Canal]], which was constructed to get logs from [[New Hampshire]] down the [[Merrimack River]] to shipbuilding centers at [[Newburyport, Massachusetts]], bypassing the 30-plus-foot drop of the [[Pawtucket Falls (Massachusetts)|Pawtucket Falls]].

In the early 1820s, [[Boston Associates|Associates]] of the recently deceased [[Francis Cabot Lowell (businessman)|Francis Cabot Lowell]] bought up the old Pawtucket Canal in what was then East [[Chelmsford, Massachusetts]].  Within a few years, the new industrial center that became Lowell was using canals feeding off a widened and deepened Pawtucket Canal as a [[hydropower|direct power source]] for their [[textile mills]].  The first of these canals was the [[Merrimack Canal]], which powered the [[Merrimack Manufacturing Company]].  The repurposing of the [[Proprietors of Locks and Canals]] allowed the Associates to sell water power to other companies, starting with the Hamilton Canal, leading to the explosive growth of the town, and then shortly thereafter, city, of Lowell.

[[File:Pawtucket Gatehouse; southwest and southeast sides; Lowell, MA; 2012-05-19.JPG|thumb|right|250px|Pawtucket Gatehouse, from the above the falls side. Barge lock chamber to the right of the gatehouse.]]

[[Image:PawtucketGatehouse2.jpg|thumb|right|250px|Pawtucket Gatehouse, from across the river, during a minor spring flood]]

By the late 1840s, Lowell's canal system was producing as much power as possible.  However, the Chief Engineer of Locks and Canals, an Englishman by the name of [[James B. Francis]] devised the Northern Canal and the Moody Street Feeder, to increase the capacity of, and availability of water to various parts of, the whole system.  The '''Pawtucket Gatehouse''' was constructed to control flow from behind the Pawtucket Dam into the Northern Canal.

The dam itself, which was built twenty years earlier, was lengthened at that time, diverting the entire Merrimack (during periods of lower flow) into the two canal system entrances above it.  It is a stone dam topped with wooden [[Floodgate#Types|flashboard]]s – a system still used on this dam today.{{update inline|date=January 2023|reason=Flashboards were replaced with pneumatic crest gates}} The level of the water is regulated by the flashboards and the metal pins that hold them back.  When there is too much water going over the top of the dam, the pins bend backwards, releasing the boards, and the outflow of the dam is increased.

The Gatehouse contains ten wooden gates that control the flow of the Merrimack into the canal.  Originally, they were opened{{clarify|date=December 2015}} by a [[Francis Turbine]], also an invention of James B. Francis.  Today, the Gatehouse is controlled electrically and remotely by Boott Hydroelectric, who is partially a continuation of the Proprietors of Locks and Canals, and who operates a 24-megawatt [[hydroplant]] on the Northern Canal.

The Canal System and the Gatehouse were designated a [[List of Historic Civil Engineering Landmarks|Historic Civil Engineering Landmark]] by the [[American Society of Civil Engineers|ASCE]] in 1984<ref>[http://live.asce.org/hh/index.mxml?lid=168 ASCE Landmark page] {{webarchive|url=https://web.archive.org/web/20120314072201/http://live.asce.org/hh/index.mxml?lid=168 |date=2012-03-14 }}</ref> and a [[List of historic mechanical engineering landmarks|Historic Mechanical Engineering Landmark]] by the [[ASME]] in 1985<ref>[http://files.asme.org/ASMEORG/Communities/History/Landmarks/5589.pdf ASME Landmark report] {{webarchive|url=https://web.archive.org/web/20110816073913/http://files.asme.org/ASMEORG/Communities/History/Landmarks/5589.pdf |date=2011-08-16 }}</ref> and are part of [[Lowell National Historical Park]].  It was added to the [[National Register of Historic Places]] in 1976, and declared a [[National Historic Landmark]] the next year.<ref name="nris"/><ref>[http://tps.cr.nps.gov/nhl/detail.cfm?ResourceId=1675&ResourceType=District NPS NHL Listing info] {{webarchive|url=https://web.archive.org/web/20120401071603/http://tps.cr.nps.gov/nhl/detail.cfm?ResourceId=1675&ResourceType=District |date=2012-04-01 }}</ref>

==Timeline of canals==
* 1796: [[Pawtucket Canal]]
* 1822: [[Merrimack Canal]]
* 1825: Hamilton Canal
* 1828: Lowell Canal
* 1831: Lawrence Canal, Western Canal
* 1835: Eastern Canal
* 1847: Northern Canal, Moody Street Feeder, and Pawtucket Gatehouse

==See also==
*[[List of National Historic Landmarks in Massachusetts]]
*[[National Register of Historic Places listings in Lowell, Massachusetts]]

==References==
{{commons category|Lowell Canal System}}
{{commons category|Pawtucket Gatehouse}}
{{Reflist}}

==External links==
*[[Historic American Engineering Record]] documentation, filed under Lowell, Middlesex County, MA:
**{{HAER |survey=MA-1 |id=ma0543 |title=Lowell Canal System |link=no}}
**{{HAER |survey=MA-1-A |id=ma1173 |title=Lowell Canal System, Pawtucket Dam |link=no}}
**{{HAER |survey=MA-4 |id=ma0545 |title=Hamilton Canal |photos=4 |data=1 |cap=1 |link=no}}
**{{HAER |survey=MA-4-A |id=ma1179 |title=Hamilton Canal, Guard Gates |photos=6 |data=1 |cap=1 |link=no}}
**{{HAER |survey=MA-4-B |id=ma1180 |title=Hamilton Canal, Wasteway Gatehouse |photos=1 |data=1 |cap=1 |link=no}}
**{{HAER |survey=MA-5 |id=ma1039 |title=Western Canal |photos=3 |data=1 |cap=1 |link=no}}
**{{HAER |survey=MA-5-A |id=ma1181 |title=Western Canal, Hickey Hall Dam |photos=5 |data=1 |cap=1 |link=no}}
**{{HAER |survey=MA-5-B |id=ma1182 |title=Western Canal, Tremont Gatehouse |photos=4 |data=1 |cap=1 |link=no}}
**{{HAER |survey=MA-5-C |id=ma1183 |title=Western Canal, Guard Gates |photos=4 |data=1 |cap=1 |link=no}}
**{{HAER |survey=MA-6 |id=ma1038 |title=Lawrence Canal, Lawrence Dam |photos=3 |data=1 |cap=1 |link=no}}
**{{HAER |survey=MA-7 |id=ma0544 |title=Eastern Canal |photos=5 |data=1 |cap=1 |link=no}}
**{{HAER |survey=MA-7-A |id=ma1184 |title=Eastern Canal, Boott Dam |photos=3 |data=1 |cap=1 |link=no}}
**{{HAER |survey=MA-7-B |id=ma1185 |title=Eastern Canal, Boott Penstock |photos=2 |data=1 |cap=1 |link=no}}
**{{HAER |survey=MA-8 |id=ma0547 |title=Northern Canal |photos=7 |data=1 |cap=1 |link=no}}
**{{HAER |survey=MA-8-A |id=ma1186 |title=Northern Canal, Pawtucket Gatehouse |photos=16 |dwgs=1 |data=1 |cap=2 |link=no}}
**{{HAER |survey=MA-8-B |id=ma1187 |title=Northern Canal, Great River Wall |photos=14 |data=1 |cap=2 |link=no}}
**{{HAER |survey=MA-8-C |id=ma1188 |title=Northern Canal, Waste Gates |photos=8 |dwgs=5 |data=1 |cap=1 |link=no}}
**{{HAER |survey=MA-9 |id=ma0546 |title=Moody Street Feeder |photos=2 |data=1 |cap=1 |link=no}}
**{{HAER |survey=MA-9-A |id=ma1189 |title=Moody Street Feeder, Gatehouse |photos=6 |data=4 |cap=1 |link=no}}

{{Massachusetts canals and reservoirs}}

[[Category:Historic Civil Engineering Landmarks]]
[[Category:Canals in Lowell, Massachusetts]]
[[Category:Infrastructure completed in 1821]]
[[Category:National Historic Landmarks in Massachusetts]]
[[Category:Historic districts in Middlesex County, Massachusetts]]
[[Category:National Register of Historic Places in Lowell, Massachusetts]]
[[Category:Locks on the National Register of Historic Places]]
[[Category:Historic American Engineering Record in Massachusetts]]
[[Category:Historic districts on the National Register of Historic Places in Massachusetts]]
[[Category:Canals on the National Register of Historic Places in Massachusetts]]
[[Category:Transportation buildings and structures on the National Register of Historic Places in Massachusetts]]
[[Category:Water transportation buildings and structures on the National Register of Historic Places]]
[[Category:Gatehouses (waterworks)]]