Maintenance of Counter Sites

Regardless of the type of counter used to monitor fish passage, an essential component of their successful operation is regular preventative maintenance. Even where regular maintenance is carried out, due to general operating conditions and occasional flood damage, counter installations and CCTV systems can require extensive overhauls.

Rewiring Electrodes
Where resistivity counters are used, electrodes monitoring fish passage are made of stainless steel. However, as cabling back to the counter is usually copper, if moisture comes in contact with the copper, corrosion will occur. Regular checks of copper cables should be carried out to ensure corrosion has not set in.

Screen Modifications
Steel screens are often used to guide fish passage through the counting zone. Such screens can often require regular maintenance to clear debris. Modifying the design of traditional screens can ensure that these become, effectively, self-cleaning.

System Overhaul
The installation of counters can, for various reasons, require overhauls. Where any damage or potential hazards to the installation or the data being collected are identified a complete refit may be warranted.

Checks to Electrode Contacts
Maintenance and routine check of installations can be greatly aided during low flow conditions. During the summer, access to areas can be gained that at other times of the year might prove impossible.

De-watered Fish Pass
Within the design of a fish counter installation it is important to incorporate features, such as sluice gates, to allow easy access to units usually submerged under normal operating conditions.

Refitting Underwater Lights
Under certain conditions blocking water flow to gain access can be impractical. Where this is anticipated, units such as underwater lights, can be installed specifically to allow easy future access.

Spectral Signal of a Resistivity Counter
Routine collection of standard information, such as pseudo-graphical outputs and oscilloscope traces can aid in the identification of faults within a counter system.

Maintenance Database
To ensure consistency in the maintenance of counters a standard database is used to collect all information relevant to a site during a maintenance visit. Where faults within a counter system occur an important historical record for each site is then available.