Concord, Massachusetts, US

City of Lowell to Merrimack River

Dropping down the right edge of
Middlesex Dam

Dropping down the right edge of
Middlesex Dam
Photo of Joe Fiala
by Rhonda Regan

Gauge Information

River Description

The Concord runs through the heart of downtown Lowell. While the area is highly urbanized, the city is hidden from the river by trees and thick greenery. As a result this is an attractive run even though it runs thru the heart of the city.

The Concord river has been modified, damed, and diverted into canals for hundreds of years. Most of the dams and canals have washed out or filled since the mid-20'th century, but a small hydro facility (operated by Centennial Island Hydro) was built on a 19'th century era diversion canal in the early 1980's. This newer project in the upper section diverts some of the flow from the put-in to just past Twisted Sister. The hydro facility can be seen just past Twisted Sister on the left.

Of special interest is the U.S. National Park devoted to the canal system. With special arrangement, paddlers are allowed to make use of the locks below the last rapid. Thus allowing one to use the power of the river to float oneself up to a canal for an easy paddle to your car.

The river has also been narrowed over time in an effort to gain more real estate. Therefore it does not require as much water to run as it was in its natural state. The river also has a huge watershed, encircling the towns enclosed by Westford, Shrewsbury, Hopkinton, Wayland and Bedford (36 towns total). This results in a very long boating season; the river should be runnable from late Fall and Winter (after a moderate rain) thru the spring (usually into June). The large number of wetlands, swamps, and dams in the watershed also delay the effect of rain and act as a big sponge. There is usually water for a couple weeks after any substantial amount of rain. Additionally the southern New England location close to the coast means the river is usually boatable throughout the winter and early spring.

The whitewater section has only four "named" drops or rapids, however it is packed with numerous surfing and play spots. Boaters can (and do) spend hours on this river hitting the waves over-and-over again. The whole run is only about 1-1/2 miles long and passes old mill factories and neighborhoods. If you take-out at the bottom on the Merrimack River it adds another 3/4 mile to the run.

During the months of April and May the Lowell Parks & Conservation Trust runs rafting trips in cooperation with Zoar Outdoor (water dependent).

Updated Info: There is a new put-in 100 yards upstream of the old one. It is a public park with a boat ramp and plenty of parking. It gets plenty of use from fishermen and flatwater boaters so security is better as well (03/2009).

The fence at the takeout below Middlesex Dam has been removed by the city for parking lot reconstruction. So it's no longer necessary to "hop" the fence to get to your car (03/2009).

Technical info

Put in elevation........98'
Take out elevation......55'
Total drop..............43'
Average drop/mile.......34'
Distance................1.25 miles
River width average.....35'
River geology...........schists small boulders some ledge
River water quality.....Varies, stained dark by upstream swamps.
Scenery.................Varies, urban to trees, some trash on shore.
Wildlife................Ducks, Great Blue Herons, etc.

River Paddling Season

Estimated chance (%) of finding the river runnable.
Month............% chance.................comment

January ............50%....Be cautious of ice.
February............50%....Be cautious of ice
March...............90%....Highest water month. 
April...............80%....Water holds up well. 
May ................60% 
June................20% 
July................10% 
August...............8% 
September...........20%....Tropical storms and their remains 
October.............30%....Trees go dormant less water being absorbed. 
November............60% 
December............50%....Watch out for ice late in month. 

Be aware this is averaged out over several years. The % chance refers to the probability of finding the river running on any given day. For instance a 10% probability for July means on average you can only expect 3 days of water. One year there could be 6 days in July with water other years none. 60% of all runnable days (>400cfs) are in the low to medium range. 30% are in the medium range. 10% in the medium high to high range. Spring levels are usually higher than fall levels. Flows on the Concord river usually peak 40 to 48 after a rain event.

Local Map - Concord river and surrounding area of Lowell

Map of Lowell, Mass. and area surrounding the river.

Map courtesy of Google Maps