Precision Water Level Instrument
Unidata Manual 6293 - Precision Water Level Instruments Issue 2.1
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blend in with their environment. Channel changes and structures should be kept
to a minimum. Access paths should be established in ways that minimise damage.
Provision should be made for any structures to be removed and the site restored
to its original condition when the measurement project is complete.
11.4.4
Access and Security
All sites have to be constructed and operated. Good access will encourage
operators to carry out regular inspections which will in turn improve the quality
of the site data.
A major cause of data loss is interference by curious people or animals, and
vandalism. All instruments should be inside locked cabinets and the floatwell
design should not allow people to reach in and disturb the float system.
11.5 Other Features of a Floatwell Site
It is important that there is a permanent check gauge or measuring device near the
floatwell from which the water level can be measured. This can be:
•
A staff gauge or scale on a stable and permanent post located near the
floatwell and surveyed to a known datum.
•
A reference point at a known level from which a vertical distance can be
measured to the water surface.
These measurements are used as a check to compare the levels recorded by the
instrument system.