Imelda - sadly you will struggle to find any decent open water swimming spots bar the sea despite us having some cracking reservoirs locally like Arlington and Bewl, or even Darwell near Battle - they are just not open to swimming.
obviously you have a choice of pools in the area - my choice is the Uni pool in Eastbourne but you need to be a member and it has time restrictions due to Uni use.
I would't use Cuckmere Haven - the river there has a strong tidal flow in both directions and although less at low and high tides could still cause problems. very little water traffic bar canoes at times but still best to avoid imho. the banks are also extremely muddy so if you get into difficulties then you'd struggle to get out
Weirwood Reservoir near Forest Row is open to swimmers with East Grinstead tri club but it has time restrictions, is summer only, and at the mo has a very low water level. going further afield there are other venues near to Tonbridge and Ashford but they will be too far away for you without a car.
there are some other smaller lakes/ponds that are used for tris - Piddinghoe at Newhaven and Ashburnham Place near Battle but they are only used for events and aren't open for general swimming.
we've looked at swimming in a couple of other areas locally - the lake at Shinewater for instance and the large level that crosses the Marsh Road between Pevensey and Little Common (Wallers Haven), but haven't tried them. Shinewater is likely to be too shallow and muddy.
looks like it's the sea or nowt
Edited: 31/08/2011 at 14:40