Chart Y17 has been withdrawn and replaced by two new charts for 2022, providing coverage of Rivers Colne & Blackwater (Y17A) and Rivers Crouch & Roach (Y17B) at an improved larger scale.This chart covers the Rivers Crouch & Roach and their approaches. It includes the latest official UKHO data, combined with additional information sourced from Imray's network to make it ideal for small craft. The chart has been fully revised throughout.Plans included:Burnham Yacht Harbour (1:12 500)River Crouch continuation to Battlesbridge (1:35 000)River Roach continuation to Rochford (1:35 000)