In 1793 The Chelmer and Blackwater Navigation Company was formed in order to deepen, widen and straighten the river so that it could be navigated and used to bring goods from the coast into Chelmsford. After commercial use of the river ceased in the 1970's, its main use is now for pleasure craft, eg narrowboats, although the navigation was built for 60ft broad beam barges. www.essexwalks.com/walks/ulting.html