Stop 17: A careful balancing act

The pond on the far side of the towpath from the canal is used to help control water levels in the canal and water flows away from the canal.

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To prevent damage to canal structures is important to keep the water levels in the canal as stable as possible. So at times of heavy rain and at other times when there is more water coming into the canal than usual, there are a number of weirs and sluices that can be used to let water out.

Sometimes this water will go directly into a ditch or stream, but if this would risk flooding then the water will first pass into a balancing pond such as this one. Water will spill over a weir or through a sluice, under the towpath in a pipe and then into the pond where it will be held back for a short time, therefore reducing pressure on the local drainage system.

Wildlife pond

As well as being very useful for water control, the pond is also very good for wildlife.  Some of the plants for which the canal is important, are in these ponds, such as curled leaved and fennel pondweed.

Amphibians use the ponds for breeding and in spring masses of frog and toad spawn can be seen, which later in the year are replaced by countless tadpoles. If you look very carefully you may also spot newts that also breed in the ponds.

Dragonfly larvae will live amongst the reeds. These fearsome predators will feed on almost anything including tadpoles and even small fish! Once they have spent 2-3 years under the water they take a long and hazardous journey up a reed stem, where they will metamorphose into an adult dragonfly. It will spend the rest its life (just a few weeks) feeding on the wing and breeding.

Last date edited: 17 July 2015