Letter: Is River Flow Speed Properly Appreciated in Weir Repair Planning?

Published on: 17 Apr, 2020
Updated on: 17 Apr, 2020

From: Jim Allen

In response to: Weir Repair Will Take Two Years

Interesting comments, but no mention of running the river at high speed during flooding undermining the weir sitting at 90 degrees to the natural flow. Nor the reason for this, the Mill race being blocked by the generator which could not cope with full race capacity/flow, thus forcing more water than designed over the weir.

Noting this practice at Bowers Lock sluice, a hole was dug 12ft (3.7 m) deep in front of the gates when the man-made Navigation is only 4ft “dug” depth. Reason for the failure to understand water flows and the Hjulström curve was nothing to do with a “weak structure” but because of water-flow management in the Wey valley basin over the past 20 years.