Higganum Reservoir, Haddam

2004 Aquatic Plant Survey of Higganum Reservoir

Transect Data | Water Data

The Higganum Reservoir in Haddam reaches a maximum depth of 34 feet near the dam built on the northern end. Houses have been built along much of the eastern side of the reservoir and along the north end of the western side. Only four aquatic plant species were recorded in Higganum Reservoir in July 2004, several months after a dam-replacement project was finished and the reservoir was refilled. The 31-acre reservoir had been drained three years earlier, when an earlier dam was declared unsafe.

Water smartweed (Polygonum amphibium) was the most abundant plant in July 2004, occurring in scattered patches in water less than 6 feet deep at the pond’s southern end. Three other plants, also found in shallow water in the southern part of the pond, were hiddenfruit bladderwort (Utricularia geminiscapa), watershield (Brasenia schreberi), and spiral pondweed (Potamogeton spirillus). The patches of water smartweed were scattered along the eastern and western shores. Watershield and spiral pondweed were found along the eastern shore, and hiddenfruit bladderwort was recorded near an unimproved state boat ramp on the western shore.

Three additional aquatic plant species, yellow water lily (Nuphar variegata), white water lily (Nymphaea odorata), and slender naiad (Najas flexilis), were recorded during a brief survey in September 2004. Only a few plants of each species were found, all occurring in the southern part of the reservoir.