Connecticut State The Connecticut Agricultural Experiment Station

Upper Moodus Reservoir, East Haddam
Upper Moodus Reservoir, East Haddam - 2016
Upper Moodus Reservoir, East Haddam

Upper Moodus Reservoir is a 440-acre waterbody located in East Haddam, CT. It is a public lake with access on the northwestern portion of the reservoir. The reservoir has an impoundment separating Upper and Lower Moodus on the north end. There is a 35 MPH speed limit during the day and an 8 MPH speed limit between 9 p.m. and 8 a.m. The reservoir is highly developed on the western half with little development on the eastern half.

The CAES IAPP 2016 survey of Upper Moodus Reservoir was a resurvey, and year to year comparisons were provided to stakeholders in a formal report. The first survey was conducted in 2012. The 2016 survey found 37 aquatic species, three were invasive: fanwort (Cabomba caroliniana), variable-leaf watermilfoil (Myriophyllum heterophyllum), and curlyleaf pondweed (Potamogeton crispus). The abundance of fanwort and variable-leaf watermilfoil decreased dramatically since 2012, probably because of a targeted herbicide application. Curlyleaf pondweed maintained a small abundance in three different areas throughout the reservoir, similar to 2012.

Floating leaf species also had a dominated the lakes eastern half and along most of the shoreline. These included watershield (Brasenia schreberi), yellow water lily (Nuphar variegata), and white water lily (Nymphaea odorata). Other species that occurred often were large-leaf pondweed (Potamogeton amplifolius), snailseed pondweed (Potamogeton bicupulatus), and ribbon-leaf pondweed (Potamogeton epihydrus). There was a substantial increase in native Robbins' pondweed (Potamogeton robbinsii) along much of the reservoir. This plant is rarely a nuisance as it grows close to the bottom. Common bladderwort (Utricularia macrorhiza) was found throughout the lake and often was floating in mats that were a minor nuisance. Concern that this plant was invasive swollen bladderwort (Utricularia inflata) proved unfounded.
Species recorded in our 2016 survey of Upper Moodus Reservoir.
Scientific Names
*Invasive Species
Arrowhead Floating bladderwort Primrose-Willow Spikerush Watershield
Bur-Reed Golden hedge-hyssop Purple bladderwort Spineless hornwort Waterwort
Common bladderwort Great duckweed Quillwort Spotted pondweed Western waterweed
Common duckweed Humped bladderwort Ribbon-Leaf pondweed Variable pondweed White water lily
Coontail Large-Leaf pondweed Robbins' pondweed Variable-Leaf watermilfoil* Yellow water lily
Curlyleaf pondweed* Leafy pondweed Slender naiad Water plantain
Eelgrass Lesser bladderwort Small pondweed Water starwort
Fanwort* Pickerelweed Snailseed pondweed Watermeal
Other Upper Moodus Reservoir Surveys: 2012