The Chelmer and Blackwater Navigation is the canalisation of the Rivers Chelmer and Blackwater in Essex, in the east of England.
The navigation runs for 13.6 miles (22km) from Springfield Basin in Chelmsford to the sea lock at Heybridge Basin near Maldon. It has 13 locks, including a flood lock, and drops 23 metres (75.4 feet) from the basin to the sea.
An Act of Parliament was passed in 1793 authorising the construction of the navigation and work began in October of that year, with John Rennie as Chief Engineer but with Richard Coates in charge in practice as Resident Engineer. His grave stands in Springfield churchyard.
The first section from Heybridge Basin to Little Baddow opened in the spring of 1796 and the navigation was opened throughout on 3 June 1797.
The first inland gasworks in Britain was built in Chelmsford using coal brought up the navigation. At its peak in the mid 19th century, the canal was carrying over 60,000 tons of cargo per year.
This slowly declined until the last load of timber was delivered to Browns Yard (now Travis Perkins) on Springfield Basin in 1972. Although commercial traffic ceased that year, the navigation has since survived solely on leisure traffic and by selling the wood from the willows that grow on the banks for making cricket bats.
The navigation is unusual in that in 1948 it was not nationalised along with most other waterways in the UK and is still under the control of the original Company of Proprietors of the Chelmer &Blackwater Navigation Ltd.
In 2003 the aforementioned went into administration and, in November 2005, The Inland Waterways Association (IWA) signed a maintenance and operating agreement with the Administrator to take over responsibility for the running of the navigation through a wholly owned subsidiary Essex Waterways Ltd.
