Before revision: The high reference water level (MHW) is sometimes set to accommodate the short-term variations (for exampke , tidal effects, usually at the levels observed 1% of the time) and the effect of water level changes due to the operation of locks and weirs.
After revision: The high reference water level (MHW) is sometimes set to accommodate the short-term variations (for example , tidal effects, usually at the levels observed 1% of the time) and the effect of water level changes due to the operation of locks and weirs.