The warm days of summer by now are a pleasant memory, running, jumping from the dock, boating and swimming.  The warm waters of Conway Lake that cooled you off on even warmer August days are part of summer enjoyment on a New Hampshire lake.  But as summer [...]]]>

Layers form in Conway Lake during the summer.

The warm days of summer by now are a pleasant memory, running, jumping from the dock, boating and swimming.  The warm waters of Conway Lake that cooled you off on even warmer August days are part of summer enjoyment on a New Hampshire lake.  But as summer wanes seasonal changes begin.  Lakes in New Hampshire and throughout New England begin to cool during September and continue into October and November.  The seasonal changes in lake temperature are an important part of the renewal of Conway Lake’s ecosystem.

One of the characteristic fall changes that happens on Conway Lake is fall “turnover”.  Fall “turnover’ is essentially a complete mixing of water in the lake, from bottom to top to bottom.  The reason why this happens in autumn (and spring too) has to do with the unique way water freezes.  Water, unlike other substances becomes less dense when it freezes.  That is why ice floats.  All other types of matter become most dense at freezing and therefore would sink.  As it turns out water is most dense at 4 degrees celcius.  That means that in a deep lake the water at the bottom will usually be around 4 degrees celcius.  Warmer water is less dense and therefore floats.  The result is that the lake forms two nearly distinct layers which do not mix.

As the the air temperature begins to cool in autumn the surface water cools as well.  When the water at the surface reaches 4 degrees celcius the entire water column (from top to bottom) is one layer.  Throw in typically windy days and the lake can now mix thoroughly.  This mixing from top to bottom is what is referred to as “turnover”.

Conway Lake Fall Turnover

The water at the bottom of the lake accumulates nutrients throughout the summer.  With fall turnover, nutrients are mixed throughout the water column.  This brings nutrients to the surface where algae can make us of them, although in fall this is somewhat minimal because the temperatures are cold.  At the same time, anything in that was in the surface waters can be mixed down into the lower part of the lake.  This can pose a problem for lakes that have excessive storm water run off.  Any excess nutrients washed into the lake during the fall will likely end up thoroughly mixed in the water column.

Fall turnover is a natural part of a lake’s ecosystem.  Excess nutrients are not.  If you are a Conway Lake homeowner you can protect the quality of your lake and your lakefront property by being aware possible sources of excess nutrients coming from your property.

Are you interested in owning property on Conway Lake in New Hampshire?  Search for Conway Lake properties on JTRealty.com