EMS carries out flow gauging in rivers, streams and manmade channels culverts and other constructed channels.
Different equipment and measurement techniques are used appropriate to each application. This can include area velocity probes, velocity profiling and dilution gauging.
Flow survey data capture
Flow rate, velocity and depth information is recorded at time-steps of several minutes. This information is reported back to the client in detailed and summarised form including daily minimums, maximums, averages and totals.
Data is usually collected over a number of weeks to capture significant events and a range of conditions.
River gauging often involves the use of several instruments across a river cross-section. These measure flow depth and velocity through the water column. The cross-section is measured so the relationship between depth and flow area is known allowing measurements to be resolved into flowrates. Cross-sections are chosen carefully to avoid re-circulations and moving river beds. In difficult circumstances, dilution gauging is used.
Local rainfall information may be required. In this case, rain gauges are sited appropriately around the site to record at the required interval.
Flow and water quality data can all be streamed over the internet for deployments where immediate review is required. Clients use EMS’s portal facility to view data which can be pushed regularly (e.g. every 15 minutes).