When withdrawal takes place from a permanently flowing watercourse, the minimum residual flow must be as follows:
up to a flow rate Q347of 60 l/s | 50 l/s | |
and for each further 10 l/s of flow rate Q347 | 8 l/s | , |
for a flow rate Q347of 160 l/s | 130 l/s | |
and for each further 10 l/s of flow rate Q347 | 4.4 l/s | more, |
for 500 l/s of flow rate Q347 | 280 l/s | |
and for each further 100 l/s of flow rate Q347 | 31 l/s | more, |
for 2,500 l/s of flow rate Q347 | 900 l/s | |
and for each further 100 l/s of flow rate Q347 | 21.3 l/s | more, |
for 10,000 l/s of flow rate Q347 | 2,500 l/s | |
and for each further 1000 l/s of flow rate Q347 | 150 l/s | more, |
from 60,000 l/s of flow rate Q347 | 10,000 l/s | . |
The minimum residual flow calculated according to paragraph 1 above shall be increased if the following requirements are not complied with and cannot be complied with as a result of other measures:
The prescribed water quality of the surface waters must be maintained in spite of the water withdrawal and existing wastewater discharges.
Groundwater resources must continue to be replenished such that the drinking water supply dependent on them remains available to the required extent and the water balance of soils used for agriculture is not substantially impaired.
Rare habitats and biocoenoses which depend directly or indirectly on the type and size of a body of water must either be maintained or where possible be replaced by others of a similar value unless overriding reasons prevent this.
The depth of water necessary for free fish migration must be maintained.
In the case of watercourses with a flow rate Q347 of up to 40 litres per second below an altitude of 800 metres above sea level which serve as spawning grounds or habitats for juvenile fish, the continuation of these functions must be guaranteed.