A silty tale

摘要

No one in the discussion about spending vast amounts of money on the Severn Barrage project has discussed the problem of silt. The reason there is a canal called the Gloucester & Sharpness Canal is because the Severn is severely silted for this length and unnavigable. If we build a barrier then the tidal flow will be impounded and the silt it carries in will settle out. How long before there is insufficient water impounded to generate electricity?