Cyanobacteria and the Lakes – Amanda McQuaid from NHDES discusses the importance of monitoring cyanobacteria, how to spot it and what to do if you encounter it.
Did you know?
Lake Ivanhoe (also known as Round Pond) is located in Carroll County, New Hampshire. The lake has no traditional inlets or outlets. Historically, a small stream drained Lake Ivanhoe to Great East Lake, but construction filled in that stream many years ago and now drainage flows over land to Great East Lake.The Lake Ivanhoe watershed is 455 acres (184 ha) and is 64% forested. The watershed is currently 17%, developed with 59% of the watershed being buildable area. The Lake Ivanhoe shoreline is primarily composed of low density residential houses and camps (66%). The majority of these structures (88%) are within 50 feet of the water’s edge.
Lake Ivanhoe is classified as oligotrophic. Lakes are classified based on the amount of available nutrients (Phosphorus and Nitrogen) for organisms. More fertile lakes have more nutrients and therefore more plants and algae. Oligotrophic means very little nutrients. These lakes have deep clear water, rocky and sandy bottoms, and very little algae. The fish found in oligotrophic lakes like cold, highly oxygenated water, examples include lake trout and whitefish. In oligotrophic lakes, oxygen is found at high levels throughout the water column. Cold water can hold more dissolved oxygen than warm water, and the deep region of oligotrophic lakes stays very cold. In addition, low algal concentration allows deeper light penetration and less decomposition of biological material
Total Watershed Area
|Wakefield, NH (Carroll Co.)
0.71 square miles
992,000 cubic meters
0.9 times per year
|Invasives: Lake Ivanhoe is not impacted by invasive flora or fauna such as variable milfoil. Our goal is to keep it that way. We participate in the UNH Lay Lakes Water Monitoring Program and proactively inspect boats for invasive fauna and flora before they are put in the water.|
Lake vs. Pond – So which is it?
The general distinction between pools/ponds and lakes is vague. A generally accepted definition is that ponds and pools have their entire bottom surfaces exposed to light, while lakes do not. In addition, some lakes become seasonally stratified. Ponds and pools have two regions: the pelagic open water zone, and the benthic zone which comprises the bottom and shore regions. Since lakes have deep bottom regions not exposed to light, these systems have an additional zone, the profundal. These three areas can have very different abiotic – (nonliving – physical and chemical interactions) conditions and, hence, host species that are specifically adapted to live there. So if you take our average Secchi disk measurements of 16.5 feet and the maximum depth of the lake at 20 feet you could argue that we have portions of the lake that do not receive sunlight exposure.