Broadcroft pond animation
Bob Ford, February 2004
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Although not connected with the Independent Quarry project, the ponds recently established at nearby Broadcroft Quarry
are of great interest to all involved with the restoration of quarries on Portland.
Although the ponds are small and are dry for several months of the year, they have been successful in attracting wildlife to a resource that is very scarce on Portland.
With the continued infilling of Yeolands Quarry, and the destruction of the well-known Yeolands ponds, the Broadcroft ponds have become even more important.
This animation shows the regeneration processes over a period of several years, from November 2002 to the present. It consists of a number of still images taken each month from the same position at the east end of the ponds. As well as demonstrating the same slow process of unaided natural regeneration that is planned for Independent Quarry, the images also show how difficult it is to keep water in ponds on limestone. |
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The Broadcroft ponds show a number of design features that have contributed to their success as a wildlife habitat.
These should be borne in mind when the Independent Quarry ponds are constructed.
On the negative side, the ponds were constructed with locally sourced clay containing many stones. This lack of a deep, solid clay base allows water to slowly drain away - a situation which may well worsen as plants push roots through the bed of the pond. Note that from 2005 the ponds were topped up regularly with mains water. |
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1MB version for broadband connections |