Minimum acceptable flow is the minimum flow rate to be maintained in a water course perpendicular to a structure to preserve biological balance and water usage downstream. Consequently, sampling authorisations are limited. Minimum acceptable flow is not a hydrological concept; it is a regulatory requirement in Europe.
To meet this regulatory requirement, we were asked to install a flow meter on the Vire River, slightly upstream of the “La Maugeautière” pumping station. The water course at this point is around 7 to 8m wide. During low water periods, the depth of the water barely exceeds 30cm. Furthermore, the only available place to install the flow meter is located just after a large bend.
|Uf 322 CO converter||SM 1527 wetted probes|
|Uf 821 CO||They make it possible to create two interwoven measurement chords.
Their clever installation means that they are well protected and require little maintenance.
The equipment is completed with a pressure level measuring device.
Accurate and continuous measurement, as expected by our client.
Here, the ultrasound transit time flow measurement means that:
- The full measurement scope can be covered, from low to high water levels,
- Reliable and mean measurements can be taken across the entire length of the chord, even though the velocity profile is not stable during low water periods.