[Acoustics] Index Velocity Ratings

[Nick j Everard]

All

A working group in the Environment Agency here in the UK is looking
into techniques for reviewing Stage Discharge and Index Velocity
ratings. The team is considering the frequency of routine periodic
rating reviews that are required and also what would trigger an interim
review. 

I am not a member of this team, but am advising on issues relating to
Hydro-Acoustic systems.

The suggestion is that stage discharge sites should be reviewed every
three years. The question is, should Index Velocity sites be reviewed at
a similar frequency? As the EA is very new to the Index Velocity
technique we do not yet have the depth of experience to know whether we
can apply the same rules.

Similarly, there is a suggestion that if a check gauging falls outside
of 2x standard error for stage discharge sites a review should be
triggered. Should this be the same for Index Velocity sites?

I have some feeling of what might be the right way to go about these
things but would very much welcome advice from users who have been
practising these techniques for a while longer than us!!

Many thanks for any help you can offer!

Regards, Nick Everard

Nick Everard
FMD Officer 1 (Hydrometry)
Environment Agency - W Area
Thames Region 
Windrush House
Howbery Park
Wallingford
Oxon, OX10 8BD
UK

Tel: +44 (0)1491 828400
Mobile: +44 (0)7831 559379
E-mail nick.everard at environment-agency.gov.uk
Internet www.environment-agency.gov.uk


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