Keeping water upstream
A survey of the effects of retention orifices.
M. Tilma,
P.E.V. van Walsum
P.J.T. van Bakel
A.G.M. Hermans
L.C.P.M. Stuyt
Constance
• The model SIMGRO
• The study area
• The orifice
• Results
• Conclusion
SIMGRO
Ro o t zo n e
Sp ri nk li ng f romg ro un dw ater Pu bl ic
w ater su pp lyLand use
Sp rin k lin g fr omsur fac e w ater
Su pp ly c apac ity
Surf ace w atersystem
Sub catc hm entbo un dar y
Sub sur face ir rig atio nor d rai nag e
Surf ace ru no ff
C api llar y riseo r per co latio n
A qu itar d
Phreat iclevel
252
H 0
2
H yd ro log ic al base
N od e po int fin iteelem ent g rid
1 A q uif er
A q u itard
st
Hydro lo gic al base
2 A q ui fern d
D e e lg e b ie d s -g r e n s
D e e lg e b ie d s -g r e n s
S le c h td o o r la te n d ela a g
C a p i l la ir eo p s t i jg in g
O p p e r v la k k ig ea fs t r o m in g
B e r e g e n in g u i to p p e r v la k te w a te r
L a n d g e b r u ik
w o r te lz o n e
G r o n d -w a te r -s p ie g e l
E e r s te w a te r v o e r e n d e la a g
T w e e d e w a te r v o e r e n d e la a g
H y d ro lo g is c h e b a s is
S le c h td o o r la te n d e la a g
O p p e r v la k te -w a te rg r e n s
In f i lt r a t ie o fd r a in a g eg r e n s
D r in k w a te r -o n t t r e k k in g
K n o o p p u n t v a ne in d ig e e le m e n te n -n e tw e rk
A a n v o e r
B e r e g e n in g u i tg r o n d w a te r
A a n v o e r o f a f v o e r
1. Ground water (Finite elements)
2. Surface water
3. Irrigation
4. Land cover
5. Drainage
The Beerze and Reuzel
Eindhoven
's-Hertogenbosch
TilburgBreda
StudiegebiedGrote steden Noord-Brabant Provinciegrenzen
N
20 0 20 40 Kilometers
Sandy area on the border between the Netherlands and Belgium which is distinct for a Dutch sandy area.
The Orifice in practise
h
Q
The orifice in the model
The Dam
The orifice
Placement of the orifices
Evaluation
0
0.02
0.04
0.06
0.08
0.1
0.12
18/10/'9
8
20/10/'9
8
22/10/'9
8
24/10/'9
8
26/10/'9
8
28/10/'9
8
30/10/'9
8
1/11/'9
8
3/11/'9
8
5/11/'9
8
7/11/'9
8
9/11/'9
8
11/11/'9
8
13/11/'9
8
15/11/'9
8
17/11/'9
8
19/11/'9
8
21/11/'9
8
23/11/'9
8
25/11/'9
8
date (dd/mm/jj)
afv
oe
r (m
3/s
)
Duiker
Dam
Duiker + Dam
Bovenstrooms
Discharge reduction
0
0.05
0.1
0.15
0.2
0.25
01/12/93 16/12/93 31/12/93 15/01/94 30/01/94 14/02/94Datum (dd/mm/jj)
afvo
er (
m3/
s)
Referentie
2,0 x Ma
1,0 x Ma
0,05 x Ma
When it goes wrong!
-0.3
-0.2
-0.1
0
0.1
0.2
0.3
0.4
datum (dd/mm/jj)
afvo
er (
m3/
s)
Referentie
2,0 x Ma
1,0 x Ma
0,05 x Ma
The effect of the orifice size on the discharge
0
0.05
0.1
0.15
0.2
0.25
0.3
0.35
0.4
1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39 41 43 45 47 49orde van maxima
De
bie
t (m
3/s
)
Referetie
0,05 X Ma
1,0 X Ma
2,0 X Ma
Effect of the size of the dam on the discharge
0
0.05
0.1
0.15
0.2
0.25
0.3
0.35
0.4
1 4 7 10 13 16 19 22 25 28 31 34 37 40 43 46 49
orde van maxima (-)
de
bie
t (m
3/s
)
50cm
35cm
20cm
10cm
referentie
Conclusion
• Reduction of the peek flow can be obtained
• Increase in water table height is a possible side effect
• For extreme peeks an increase in peek discharge is possible
• Careful planning is necessary