Mackenzie Reservoir, Wallingford

2005 Aquatic Plant Survey Map of Mackenzie Reservoir

Transect Data | Water Data

Mackenzie Reservoir, also known as Pine River Reservoir, has a surface area of 48.3 acres. The reservoir is divided into two sections, a northern and a southern. The southern section is considerably larger, with a dam at the southwestern and northwestern ends. The northern pond is very shallow, with a small river entering from northeast. An island exists in the wider, eastern section of the pond.  The Town of Wallingford owns Mackenzie Reservoir, but it keeps the boat launch closed to the public. The shores are largely forested, with a large grassy section along the western shore of the larger pond.

During our June 2005 survey, thirteen species of aquatic plants were observed, including the invasives Eurasian watermilfoil (Myriophyllum spicatum)and curlyleaf pondweed (Potamogeton crispus). Plants were not observed growing at depth greater than 10 feet (3 m). The northern section of Mackenzie Reservoir was carpeted with western waterweed (Elodea nuttallii), with the exception of a deeper area north of the island. Common duckweed (Lemna minor), greater duckweed (Spirodela polyrhiza), and watermeal (Wolffia species) were found thinly spread across the entire pond, with thicker cover in the coves along the shore. Small patches of the invasive Eurasian watermilfoil were found spread throughout the pond, and the invasive curlyleaf pondweed was found in the southwest portion of the lake. Coontail (Ceratophyllum demersum) was observed in the western half of the northern pond, and along the southern and northern shores in large patches, and variable pondweed (Potamogeton gramineus) was observed in these same locations. Sago pondweed (Stuckenia pectinata) was found on the south and north shores. Leafy pondweed (Potamogeton foliosus) was observed in three small patches along the shore in the western half, and water smartweed (Polygonum amphibium) was found in one small patch on the south shore.

In the larger southern section of Mackenzie Reservoir, plants mostly occurred along the edge. Eurasian watermilfoil was found in small and large patches on all sides of the reservoir, along with coontail, western waterweed, and leafy pondweed. Sago pondweed was observed in two very small patches, one at the northern tip along the dam, the other off a point in the southern portion of the west side of the reservoir. Slender naiad (Najas flexilis), curlyleaf pondweed, and variable pondweed also were found on the west side of the reservoir. In addition, slender naiad was found on the south shore, and variable pondweed was found on the east shore of the reservoir.