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The Merrimack River Canals

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After the Middlesex Canal opened in 1803, attention turned to making the Merrimack River navigable for canal boats. Many obstacles had to be overcome; from Concord, NH to Chelmsford, MA, the river fell a vertical distance of about 135 feet in a dozen waterfalls and difficult rapids.

Ascending the river from the head of the Middlesex Canal, the first obstruction was at Wicasee Falls, by Tyng's Island, where the river fell 3 feet in about a third of a mile. Fifteen miles further up was Cromwell's Falls with a 6 foot drop in a little less than three-quarters of a mile. In the nine miles upstream of the town of Merrimack, itself four miles above Cromwell's Falls, there were a total of six falls: Moor's, with a drop of 6 feet in about 650 feet; Coos (Cohas), 3 feet in 500 feet; Goff's, 6 feet in about 1100 feet; Short's, 7 feet in about 30 feet; Griffin's (probably only a foot or two); and Merrill's, 3 feet in about 160 feet. Half a mile above above Merrill's Falls was Amoskeag Falls at Derryfield (now Manchester). Here, in a series of three falls, the river fell 54 feet in a half a mile. The river was then clear upstream for about 8 miles to Hookset Falls, where there was a drop of 16 feet in about 800 feet. Seven miles beyond was Garvin's Falls, with a drop of 25 feet; and one mile beyond Garvin's there was a 5 foot drop at Turkey Falls. Competition from railroads ended canal profitability before the falls north of Concord could be effectively developed.

Over the period from 1809 to 1817, canals and locks were built at each of these sites except at Turkey Falls. the need for a canal here was eliminated by raising the water level behind the Garvin's Falls dam high enough to flood this site.

Wicasee Falls Canal -- In February 1813, following authorization by the Massachusetts Legislature, the Proprietors of the Middlesex Canal initiated work on the Wicasee canal. the lock was operable by about 1815; a lock-tender's house was added by 1817.

Sullivan described the project as follows: "A rapid for half a mile between an island and the western shore is crossed with a dam of stone and timber, 200 yards. This raises the water above about a foot, which saved digging on the other side of the island where the lock is placed. This side afforded a passage for high water, six rods wide. From the lock to its entrance is 1900 feet. This space was encumbered with masses of rock of every size and with earth, estimated at 4000 square yards. The lock is placed in the middle of the stream; its side walls are 100 feet in length, connected with the shore by wing-walls, each about 50 feet. The wing-walls are faced with plank driven into the bottom and extending into the shores. The walls, having no support, were necessarily thick to sustain the pressure of the lock and the shock of the freshets. They are 12 feet high and average 8 feet thick, containing 1200 perches. The stone was split out large and drawn half a mile, loaded for the most part onto a boat with a crane and windlass, and thence laid. The foundation was difficult, the bottom was encumbered with stones, the water from 2 to 7 feet deep and not being clear, the work of deepening, filling up, and laying the walls under water was done by feeling, diving, etc.

Cromwell’s Falls Canal - On December 17, 1812, the New Hampshire Legislature authorized J. L. Sullivan and associates as the Proprietors of the Locks at Cromwell Falls to build locks and wing dams on the westerly side of the river. A single lock, similar to the one at Wicasee, was built along with a 2000-foot dam that extended to the head of the rapid. This effort was completed by about 1815 at a cost of about $9000.

The legislature also authorized the transfer of the rights and privileges of this endeavor to the Union Locks and Canal, as an addition to their charter, which was accomplished in August of the following year.

Blodget’s /Amoskeag Canal at Amoskeag Falls —Construction of Blodget’s Canal at Derryfield (now Manchester) NH was begun by Judge Samuel Blodget following authorization by the New Hampshire legislature in December 1798. This effort also ran into extensive financial difficulties and the legislatures of both New Hampshire and Massachusetts authorized several lotteries to raise money to continue the work. The canal initially opened in 1809 with 9 locks, apparently 11’ x 100’, in a channel that ran in the river below the falls and extended for more than a mile and a third. The canal was partially rebuilt and fully repaired in 1812; it was renamed the Amoskeag Canal in 1815 and then rebuilt the following year. At that time, it appears that a new channel may have been cut into the eastern bank and the number of locks was probably reduced from nine to seven.

As they did with the Union Canal, the Proprietors of the Middlesex Canal acquired a controlling interest in the Amoskeag Canal by or before 1817.

Hookset Canal — In February 1794, Robert McGregor and William Duncan were incorporated as The Proprietors of the Isle of Hookset Canal. The Middlesex Canal Company invested in this endeavor and provided such extensive support that, by 1811, they effectively held controlling interest. Construction consisted of a 1300 foot long canal containing a guard-lock, two 10’ x 82’ lift locks, and a 250’ dam. This effort was completed in 1811 at a cost of $13,000.

Bow Canal at Garvin’s Falls — Consisted of a 1900 foot long canal containing a guard-lock, three 10’ x 90’ lift locks, and a 450’ dam across the river at the head of the falls. The canal was authorized in June 1808 and completed by 1812 at a cost of about $19,000.

Pawtucket Canal — This 9000-foot canal around the Pawtucket Fails at Middlesex Village (in what is now Lowell) was authorized in 1792 and completed in 1796 by the “Proprietors of Locks and Canals on the Merrimack River”. Initially seven locks were built; these included: a guard lock; Minx Lock; two Swamp Locks; and three Concord Locks, also called Lower Locks. The canal was rebuilt in 1822-24 to serve the dual purposes of transportation and the providing of water power to the growing mill-city of Lowell. At this time, the Minx Lock was removed and the Concord Locks were reduced to a two-lock staircase. All of the locks were rebuilt of stone with wood planking, to a length of 115 feet and a width of 25 feet. Later, in 1841, the Concord Locks were narrowed to 12 feet to save water.

In later years, three more miles of canals were added to the system, the: Merrimack Canal in 1822, Western Canal in 1832, Eastern Canal in 1836 and Northern Canal in 1848. The Northern Canal has a guard lock at its upper end, near the Pawtucket Dam, and the Western Canal had a stone two-lock staircase, near the out fall end, to provide boat access to one of the mills.

Lawrence Canal - The North Canal at Lawrence is about a mile in length and included a guard lock and three lift locks to overcome a drop of 29 feet. The locks were 20 by 100 feet and employed mitered gates. The Essex Company rebuilt the locks and the “Great Stone Dam” in 1845—48 to adapt the canal for power. The dam was a marvel of its time, up to 40 feet high and massively built of stone on bedrock; it has never needed repairs. The locks were abandoned and filled-in in the I 960s.

Nashua and Piscataguog River Canals — Canals were built on these rivers, near their junctions with the Merrimack River, to provide power and canal boat access to the respective villages and industries.

Captain Isaac Riddle, a local merchant, apparently built a short canal with several locks near the outlet of the Piscataquog River in about 1818.

Two canals were built along the Nashua River. The first of these, a power canal, began at the Mine Falls Dam and followed a three-mile channel to carry water to turbines at the Nashua Manufacturing Company. (Mine Falls Park preserves this power canal.)

The Nashua Manufacturing Company was chartered in December, 1824, to build a canal to connect the Nashua River with the Merrimack. Loammi Baldwin supervised the effort which included the building of a second dam on the Nashua River and a canal with 4 locks that met the Merrimack a short distance north of the mouth of the Nashua River. The four-lock staircase was of solid stone, 24 feet high, each lock being 10 feet wide by 82 feet in length. The effort was begun in 1825 and the canal opened in 1826. The cost of the project was $20,000 for the canal and locks and an additional $10,000 for the dam.

Union Locks and Canal Company — In December of 1808, Jonathan Eastman, Isaac Chandler, Winthrop Fifield and Ebenezer Eastman were incorporated by the New Hampshire Legislature as the Proprietors of the Union Locks and Canal. They were empowered to clear the Merrimack River from Reed’s Ferry to Amoskeag Falls and to construct the necessary locks and dams. Six canals, described below, resulted from this endeavor. However, their efforts encountered considerable technical and financial difficulty. Increasingly the Union Canal Company turned for assistance to the Middlesex Canal Company which, by 1811, had acquired a three-quarters interest and effectively controlled the Union Locks and Canal Company.

*- Moor’s — The construction at consisted of two 10’ x 82’ drop-gate locks in a towpath canal about 2000’ in length at the foot of the falls, and a dam about 3200 feet long. The work was completed by 1813 at a cost of about $15,000.

*- Coos (Cohas) — This effort consisted of building a single 10’ x 82’ drop-gate lock in a short towpath canal on the east side of the river, and a dam of about 2500 feet in length. This work was completed by 1811 at a cost of about $5,000.

*- Goff’s — A single 10’ x 82’ drop-gate lock in a short towpath canal was constructed on the west side of the river, together with a dam of about 2500 feet in length. This work was completed in 1811 at a cost of about $7,000.

*- Short’s — This endeavor consisted of a single 10’ x 82’ drop-gate lock in a short towpath canal on the east side of the river, and a dam of about 2500 feet in length. This work was completed in about 1813 at a cost of about $4,000.

*- Griffin’s — Also a Union Canal Company endeavor, a single 10’ x 82’ drop-gate lock in a short towpath canal, and a dam of about 2500 feet in length, were constructed on the east side of the river. This work was completed in 1811 at a cost of about $6,000.

*- Merrill’s — The effort at Merrill’s consisted of a towpath canal about 1600 feet long on the east side of the river, with a single 10’ x 82’ drop-gate lock, and a dam of about 2500 feet in length. This work was completed around 1813 at a cost of about $10,000.

Relative to Rafts on Middlesex Canal

THAT whereas inconveniences have arisen, on the Canal, from there not being a sufficient number of men to attend and conduct rafts: The Board of Directors, in virtue of the authority committed to them by the proprietors, do hereby make and ordain the following by-laws or regulations, viz. 

Sec. 1. It is enacted and declared, That so much of the regulations heretofore established as provides that rafts when united shall not exceed five hundred feet in length, is hereby repealed.

Sec. 2. That rafts of the size prescribed in the regulations may be united in bands not exceeding ten in number.

Sec. 3. That a band of not less than seven or more than ten rafts, shall not proceed on the canal with a less number than five men to conduct the same, including the driver of the team.

Sec. 4. That a band of four to six rafts shall not proceed on the canal with a less number than four men to conduct the same including the driver.

Sec. 5. That a band of three rafts shall not proceed on the canal with a less number than three men to conduct the same including the driver.

Sec. 6. That whenever a boat overtakes a raft, the boatman shall sound his horn or call to the raftsmen, whose duty it shall be to come without delay to the hinder part of the raft, and push the the same from the towing path side of the canal, and making sufficient room for the boat to pass conveniently by. And the raftsmen shall continue to make room for the boat till the same gets by, and shall cause the towing rope to be slackened so that the boat shall go over it. --- And when a raft shall meet a boat, the towing rope of the raft shall be likewise slackened so that the boat shall pass over the same. And it shall be the duty of the raftsmen to push their raft from the towing path so that the boat may conveniently enter between, and shall continue to make room until the boat shall have gone by.

Sec. 7. The boatmen, after calling or sounding the horn, shall steer as near to the towing path as the depth of his boat in the water will permit, and shall continue to keep thus near till he has passed the raft.

Sec. 8. As the object of these by-laws and regulations is to produce mutual accommodation and convenience to all persons navigating the canal – and as none but those who are disposed to make difficulty will occasion it – It is further enacted, That any conductor of a raft or boat who shall not conform thereto, shall forfeit and pay ten dollars to the use of the corporation, to be recovered as the law directs.

Agent of the Corporation

March 8, 1811

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