Historic Structures

Hydroelectric Facility Description Willimantic Linen Company Mill Number 2, Windham Connecticut

Willimantic Linen Company built Mill No. 2 as a random-course granite, gable-roofed, 4-1/2-story structure about 70 feet wide and, after several additions, 460 feet long, with a central stair tower and three round windows in each gable end (See Photo GENERAL VIEW TO NORTH) . Stone for the dam and mill were quarried from the river. The wheelhouse is a space beneath the first floor of a 3-1/2-story riverside ell which also included machine and carpenter shops. This space is about 71.5 by 50.25 feet in area and 25 feet high, over granite ledge (See Photo VIEW SOUTHWEST OF TAILRACE. ..; DETAIL VIEW NORTH OF WHEELHOUSE WING AND HEADGATES) . There are three 9-by-6.3-foot wooden headgates with partly intact metal rack-and-pinion operating mechanisms; original trash racks did not survive (Photo DETAIL VIEW SOUTH OF SOUTH-MOST HEADGATE OPERATING MECHANISM.. .). The gates controlled flow into three arched, granite ashlar, 10-foot-long turbine intakes running through a bulkhead on the southwest wall of the powerhouse. Each 8-by-4.5 foot intake has a 2-foot-high arch above.

Three bays, running northwest-southeast, divide the wheelhouse. The two easternmost of these bays, divided by a 34-foot arch repeated at the tailrace opening, have several levels of wooden platforms suspended from the floor above or supported by cast-iron columns resting on ledge below. The central bay contains pulley wheels and belts transmitting power from the turbines to the generator. Three turbine bays transect the westernmost wheelhouse bay, which also includes the generator. The turbine bays were originally coursed granite ashlar with low arches, built for earlier, as-yet undocumented turbine installations C1864-80. The existing facilities include later brick-and-granite arches over these bays, raised above the original arches (Photo VIEW SOUTHWEST OF TURBINE BAYS AND DRAFT TUBES).

Three 36-inch, single runner horizontal shaft turbines occupied the turbine bays, representing two generations of installation- The northernmost turbine is the oldest, a cylinder-gate unit installed by Swain Turbine & Manufacturing Company in the late 19th century. This unit was in poor condition. There was a 16.5-by-6-inch iron plate plate identifying this firm near the riveted steel draft tube, which along with the steel pressure case was identical to those of the middle and southernmost turbines.

The other two turbines, made by the S. Morgan Smith Company, were each approximately 285-hp, 185-rpm units with 18-inch-high wicket gates. Six-inch diameter steel shafts, running about 22 feet from the southernmost turbine and about 18 feet from the middle turbine, once turned 6- and 7-foot diameter (respectively) cast-iron pulley wheels. These components remained in place, but were inoperable. A 6-foot-diameter wooden wheel, identical in size to the 6-foot-wheel found in place, rested against the riverside wall of the wheelhouse in two halves, and may represent part of the Swain installation. Disarticulated leather belts 18-19 inches wide, with 52 and 38 foot shaft centers, drove a 15-kw, 120-A, 125-v General Electric D.C. motor-exciter (model 51A50) and a 500-kw, 525-KVA, 360-rpm, 600 V G.E. steel-framed generator in the northwest comer of the wheelhouse. The generator was probably purchased used from the Winslow Bros, firm in Norwood, MA after the 1938 hurricane (Photos VIEW SOUTHWEST OF TURBINE BAYS AND DRAFT TUBES; VIEW NORTHWEST OF TRANSMISSION MECHANISMS...; DETAIL VIEW SOUTHWEST OF SOUTH TURBINE DRAFT TUBE AND SHAFT; DETAIL VXEW NORTHEAST OF SOUTH TURBINE SHAFT AND PULLEY WHEEL; DETAIL VTEW WEST OF KIDDIE TURBINE DRAFT TUBE, SHAFT, AND PULLEY WHEEL; DETAIL VIEW NORTH AND WEST OF GENERATOR...; DETAIL VIEW WEST OF MIDDLE TURBINE PRESSURE CASE...; DETAIL VIEW NORTH OF MIDDLE TURBINE WICKET GATES).

The 38-to-40-foot-wide tailrace had an intact granite rubble south wall, 6 to 12 feet high, and a partly collapsed, 24-foot-high, granite and concrete north wall; the concrete represented previous repairs (VIEW SOUTHWEST OF TAILRACE. ..).