I took these two pictures while sailing up the Colne in a Mirror dinghy one bright Boxing Day sometime at the end of the 1960's or beginning of the '70s. The view above looks much the same today, but there are some marked changes just a little downstream with the building of a tide barrier, this being a hydraulically operated gate accross the river. The tide barrier is normally open so is not really any impediment to navigation.
If you are visiting the Coln in a cruising dinghy there is a 2/3rds tide landing place on the east bank a little above the entrance to Arlesford Creek. I cannot say that you may camp ashore here but I have sometimes seen small tents set up in that vicinity. Just above the beach is a disused railway line, now a footpath, which makes a pleasant evening stroll for a mile or so up the river for an evening meal at one of the pubs in Wivenhoe.
If you do visit Wivenhoe I can recommend a visit to the NOTTAGE INSTITUTE (if it is open) which is one of the buildings on the waterfront pictured above. This is a kind of combination of a museum and an educational institution with a nautical slant. One of the courses they offer is a boatbuilding course during which you build yourself a real clinker boat.
The picture above is Wivenhoe shipyard, again taken long ago. Today you may notice some conrete work which is the remains of the foundations, but not much else. I understand that this shipyard went bankrupt due to losses incurred in building the sail training vessel that the UK provided as a 200th birthday present to Australia. Back in the '60s this seemed a very busy place, there was always a small ship or two under construction, and it survived for longer than most of the other British shipyards. It seemed incongruous to come accross a shipyard, even a relatively small shipyard, in a fairly quiet village in the countryside, quite a few miles up a narrow river from the sea.