jayne.....Don't know where you live in Essex but a couple of the quieter sites near Colchester may be worth a look:
1) Colchester Camping....This used to be, until this year, one of the Caravan Clubs Affiliated sites, but they are now in private hands. The standards are good but if you do go pitch to the reception side of the site away from the A12 which can be noisy.
2) Homestead Caravans, Weeley nr Clacton. This is a caravan dealers showroom and accesorry shop. They have an excelent campsite adjoining with a lake and fishing. I think they are also developing some log cabins for siting around the lake. I have not stayed overnight but when I bought my new van from them I borrowed a pitch for a few hours to ensure everything was working and we set up our new awning at the same time It is a quiet site but is close to the coast.