Modelling of stormwater infiltration for stream restoration. Beder

Modelling of stormwater infiltration for
stream restoration. Beder (Aarhus) case
study
Luca Locatelli
Phd Student
DTU - Environment
B. Bockhorn, (KU), K.E. Klint, (GEUS), O. Mark, (DHI), P.S. Mikkelsen,
(DTU), H. Olesen, (ORBICON), N. Bischoff, (ORBICON), P.J. Binning, (DTU).
The idea of the project
Stormwater infiltration can contribute to streamflow
Aim of the project
To model the impact of stormwater infiltration in Beder
• Annual water balance
• Risk of polluting the primary aquifer
• Flow in Hovedgrøften during periods of low stream flow
The case study (1)
The model area
The case study (2)
The geology of the area
The case study (3)
The primary aquifer
The case study (4)
The observed water level in the boreholes
The case study (5)
The stream catchment
The model (1)
MIKE SHE – MIKE 11
10 x 10 m grid
Calibration and validation (2003-2008)
The model (2)
Scenarios:
1 BASELINE SCENARIO
2 REALISTIC INFILTRATION SCENARIO
to infiltrate stormwater runoff from an area of 6.8 hectares having
25% imperviousness.
3 POTENTIAL INFILTRATON SCENARIO
to infiltrate stormwater runoff from an area of 1.5 km2 having 25%
imperviousness.
Conclusions
• Stormwater infiltration in Beder poses risk to drinking water wells
• 66-73% of infiltrated stormwater runoff reaches the primary
aquifer.
• Realistic infiltration scenario contribute 0.1% to low stream flows
of Hovedgrøften
• Potential infiltration scenario contribute 11% to low stream flows
of Hovedgrøften
• More widespread stormwater infiltration in the catchment will
likely increase streamflow during dry periods.
Acknowledgment
Thanks to Aarhus Vand
Thank you for your attention
Luca Locatelli
[email protected]
Well number