Controlled drainage with subirrigation A management measure to discharge, retain, and recharge fresh groundwater Janine de Wit (KWR & WUR) Marjolein van Huijgevoort (KWR), Gé van den Eertwegh (KnowH2O), Dion van Deijl (KnowH2O), Jos van Dam (WUR), Ruud Bartholomeus (KWR & WUR) 10th November 2022, Brussel, Belgium

1. 10th November 2022, Brussel, Belgium
Controlled drainage
with subirrigation
A management measure to discharge, retain, and
recharge fresh groundwater
Janine de Wit (KWR & WUR)
Marjolein van Huijgevoort (KWR), Gé van den Eertwegh
(KnowH2O), Dion van Deijl (KnowH2O), Jos van Dam (WUR),
Ruud Bartholomeus (KWR & WUR)
© Authors. All rights reserved
Studiedag - Peilbeheer: monitoring, modellering en
beheer

2. 2
Small introduction
• Janine de Wit (MSc.)
• Researcher Ecohydrology – KWR Water Research Institute, Nieuwegein, NL – (2019 – ..)
• PhD Student – Wageningen University – (2020 – ..)
• Scientific, applied research in the (drinking) water sector.
- Unsaturated zone, groundwater, droughts, water availability, freshwater system,
drainage systems
- Data collection (fieldwork) / data analyses / modelling

3. 3
Why do we have to worry about water when we live in a Delta?
Dry
Colijnsplaat (NL), November 2019 Colijnsplaat (NL), June 2020
Wet
Colijnsplaat (NL), July 2021
wet

4. 4
• Drainage, land consolidation, urbanization, economic growth, increased food demand, climate change, weather extremes
• Drainage: only when needed
• Retention and water supply when and where possible
Developments + challenges in the Netherlands (1950-2020)
Impacts on landscape design and groundwater levels
De Wit et al. (2022)
De Wit, J.A., Ritsema, C.J., Van Dam, J.C., Van den Eertwegh, G.A.P.H., Bartholomeus, R.P., 2022. Development of subsurface drainage systems:
Discharge – retention – recharge. Agricultural water management. DOI: 10.1016/j.agwat.2022.107677
Bron: Knelpuntenanalyse Deltaprogramma
Zoetwater

5. Discharge – retention – supply
Example: controlled drainage and subirrigation
www.stowa.nl/lumbricus | Bartholomeus et al. (red) (2021)
Bartholomeus (red.), R.P., 2021. Programma Lumbricus - Integrale benadering van een klimaatrobuuste inrichting en
beheer van stroomgebieden. Een overzicht. STOWA 2021-05. Stichting Toegepast Onderzoek Waterbeheer, Amersfoort.
No drainage Conventional (II)/ Controlled (III) drainage
Composite controlled drainage Composite controlled drainage with
subirrigation
I
II
I
IV-
1
IV-2
V
II
De Wit et al. (2022)
De Wit, J.A., Ritsema, C.J., Van Dam, J.C., Van den Eertwegh, G.A.P.H., Bartholomeus, R.P., 2022. Development of subsurface drainage
systems: Discharge – retention – recharge. Agricultural water management. DOI: 10.1016/j.agwat.2022.107677
Discharge
Discharge,
Retain
Discharge,
Retain,
Recharge

6. 6
Field experiments in NL
Subirrigation
• Several field sites with controlled drainage with subirrigation
Colijnsplaat

7. 8
Field experiments – sub-irrigation
Comparable experiments, some different characteristics
Stegeren (Ov) Lieshout / Bavaria (NB) Haaksbergen (Ov) America (L)
Stegeren (Ov) Lieshout (NB) Haaksbergen (Ov) America (L) Colijnsplaat (Z)
Water supply source Surface water Treated waste water (industry) Treated waste water (domestic) Groundwater Bassin (precipitation)
MxG MHG [cm-ss] ± 80 ± 100 ± 25 ± 90 ± 90
MLG [cm-ss] ± 120 ± 230 ± 100 ± 180 ± 170
Soil Sand,
loam - none
Sand,
Loamy layers > 1 à 1.5m
Sand,
Loamy layer ± 30 cm > 3m
Sand,
Loamy layer ± 20 cm > 2.20m
Clay
Colijnsplaat (Z)

8. 9
Results – GWL and soil water potential
© KWR
• The soil is wetter with subirrigation
than without
• Most effect at 60 cm-ss, then 40 cm-ss,
then 20 cm-ss © KWR
© KWR
± 20 cm ± 100 cm
Sub period
No sub period

9. 10
Results – The water balance
De Wit et al. (2022)
De Wit, J.A., Ritsema, C.J., Van Dam, J.C., Van den Eertwegh, G.A.P.H., Bartholomeus, R.P., 2022. Development of subsurface
drainage systems: Discharge – retention – recharge. Agricultural water management. DOI: 10.1016/j.agwat.2022.107677
de Wit, J.A., Van Huijgevoort, M.H.J., Van Deijl, D., Van den Eertwegh, G.A.P.H., Bartholomeus, R.P., 2021. Regelbare
drainage met subirrigatie en slimme stuwen - Veldproeven en modelanalyses in het zandgebied van Nederland voor een
robuustere waterhuishouding op lokale en regionale schaal. KWR 2021.028. KWR, Nieuwegein.
De Wit et al. (2021)
• Controlled drainage with subirrigation requires water
• Subirrigation alters the water balance components

10. 11
• Subirrigation alters the
water balance
components, but also
depend on
hydrogeological
characteristics
Water balance – hydrogeological effects
De Wit et al. (in prep)
© KWR © KWR
De Wit et al. (in prep)

11. 12
Controlled drainage with subirrigation internationally
De Wit et al. (2022)
De Wit, J.A., Ritsema, C.J., Van Dam, J.C., Van den Eertwegh, G.A.P.H., Bartholomeus, R.P., 2022. Development of subsurface drainage
systems: Discharge – retention – recharge. Agricultural water management. DOI: 10.1016/j.agwat.2022.107677
• Drainage systems are
commonly applied in the world
• General observations
- Pipe infiltration
- ETact (depends on GWL)
- Downward seepage

12. Work in progress: Water system thinking and modelling
Propagation, benefits and risks of measures
© KWR
Figure by Sija Stofberg
Pronk et al. (2021)
Think integrated:
the whole water system needs to be
considered
Optimizing subirrigation
(use less water while crop
conditions are optimal)
Proper management
(technical + environment)
Source of water: surface water,
treated waste water, groundwater
Optimizing Management Water source Whole water system

13. 14
Optimizing subirrigation - example
• 4 farmers with controlled drainage with subirrigation
• Goal: improve the growing conditions for crops
Step 3: Optimization crest level
1. Oxygen stress: KAD level down  drainage
2. Drought stress: KAD level up  retain water
3. Correct conditions: KAD level remains
Monitoring together (farmers – researchers)
• Goal: learn together from pilots
• Frequent hand measurements
• Online data portal  check up-to-date
measurements
• Questions: communication via whatsapp
Automated online control
Pilot Stegeren
• Goal: optimize growing conditions for crops with
controlling the drainage level
Locatie Stegeren Step 1: Calibration SWAP model with field measurements
Step 2: Forecast growing conditions with the SWAP
model with the actual weather forecast
Crest, present in
the control pit
Equipment in
Stegeren

14. 15
Proper management – example

15. 17
Regional water system – example
Pronk et al. (2021)
Brakkee et al. (2021)
• 6 farmers
• Regional effect on groundwater level
and water balance components
• Regional water demand & water supply
Heijmans et al. (2022)

16. 18
Take home message
Why do have to worry about water when we live in a Delta?
• To ensure enough water, of enough quality at the right place and time
• Controlled drainage with subirrigation systems could:
- Local scale: raise the groundwater level and increase soil moisture availability for crops
- Regional scale: reduce peak discharges, discharge less water, and increase groundwater
recharge
• Operational management (by farmer)
- Training, capacity building, evaluation, etc.
! Think integrated:
The whole water system needs to be considered !
De Wit et al. (2022)
© KWR

17. KWR_Water
KWR
@KWR_Water
T +31 (0)30 60 69 511
E info@kwrwater.nl
I www.kwrwater.nl
Groningenhaven 7
3433 PE Nieuwegein
The Netherlands
Ruud Bartholomeus
ruud.bartholomeus@kwrwater.nl
Janine de Wit
janine.de.wit@kwrwater.nl
+31 6 15616926
And colleagues