1. Halil Önder Department of Civil Engineering METU Ankara, Turkey
24-Apr-17
Use of Underground Dams in the Sustainable Developement and Management of Groundwater Resources
Halil Önder
Department of Civil Engineering
METU
Ankara, Turkey
Halil Önder
5. World Water Form Istanbul
Halil Önder

2. Outline objective sustainability of groundwater, goals, strategies
underground dams
use of underground dams
technical effectiveness and performance evaluation
discussion and conclusion
Halil Önder
5. World Water Form Istanbul

3. Objective
To discuss and demonstrate the use of underground dams in the sustainable developement and management of groundwater resources in rural areas for small communities
To draw a conclusion
Halil Önder
5. World Water Form Istanbul

4. Groundwater Sustainability and Goals
Definition
The groundwater sustainability is defined as development and use of ground water in a manner that can be maintained for an indefinite time to meet both current and future beneficial purposes without causing unacceptable environmental, economic, or social consequences
USGS (circular 1186)
Goals
sustainable long term yields from aquifers
effective and efficient use of stored water in aquifers
preservation of water quality
preservation of water dependent ecosystems -aquatic environments
maintenance of base flow
integration of groundwater and surface water into a comprehensive natural resource management system
Halil Önder
5. World Water Form Istanbul

5. Management strategies to ensure the sustainability:
decrease discharge from groundwater system
increase recharge to groundwater system
change rates or spatial patterns of groundwater pumpage
change the volume of groundwater in storage at different time scales
USGS
Intelligent tools and innovative approaches to enhance the sustainability of groundwater resources
Groundwater Dam is an example
Definition:
Any structure designed to contain underground flow from a natural aquifer or from an artificial one, built with an impermeable barrier
Types:
Sub-Surface Dams
Sand-Storage Dams
Halil Önder
5. World Water Form Istanbul

6. Types of Sub-Surface Dams
a) Clay dike, b) Concrete dam, c) Stone masonry dam, d) Reinforced concrete dam, e) Plastered brick wall, f) Plastic or tarred-felt sheets, g) Corrugated iron, steel, or PVC sheet, h) Injection screen (Nilsson, 1988)
Halil Önder
5. World Water Form Istanbul

7. Types of Sand-Storage Dams
a) Concrete sand-storage dam, b) Stone masonry sand-storage dam, c) Gabion sand-storage dam with clay cover, d) Gabion sand-storage dam with clay core, e) Stone-fill concrete sand-storage dam, f) Stone sand-storage dam (Nilsson, 1988)
Halil Önder
5. World Water Form Istanbul

8. Examples
Halil Önder
5. World Water Form Istanbul

9. Characteristics and Attractiveness of Underground Dams:
low in capital cost
an appropriate technology for the poorer communities
requires essentially no external resources, use of local material is possible
needs little expertise to run and maintain, can be understood, controlled and maintained by local people
are relatively easy to make and very cheap to construct
contributes to the decentralization of water management
are able to store larger volume of water
small enough in scale to be afforded by a small group of people
Halil Önder
5. World Water Form Istanbul

10. Basic Utilizations of Underground Dams:
basic water supply for
domestic use,
small-scale (manual) irrigation,
industrial use
livestock watering
to prevent salt water intrusion in coastal aquifers
combating or reversing the process of desertification
treated waste water may be stored behind underground dam for non-potable purposes
for artificial recharge
to construct artificial wetland
source of water for natural wetlands
Halil Önder
5. World Water Form Istanbul

11. Utilisation of Underground Dams-1
reducing the impact of saltwater intrusion by construction or installation of an impermeable subsurface barrier paralleling the coast
decreasing discharge from groundwater system into the sea (subsurface dam is recomended near the sea shore to prevent the subsurface flow from the aquifer to the sea)
Halil Önder
5. World Water Form Istanbul

12. Utilisation of Underground Dams-2
combating or reversing the process of desertification
Halil Önder
5. World Water Form Istanbul

13. Utilisation of Underground Dams-3
treated waste water may be stored behind underground dam for non-potable purposes
an interesting method to achieve groundwater sustainability
augmenting and enhancing the available groundwater resources
treated waste water is:
available for reuse at a relatively low cost
provides a dependable source of water even in dought years
eliminates the need for costly waste water disposal options
Halil Önder
5. World Water Form Istanbul

14. Management of the groundwater resources
management involves complete understanding of the cause and effect relationship that the human activities have on the groundwater resources and on the broader environment.
in this context groundwater modeling constitutes an important task.
performance evaluation is done by using numerical simulation
numerical technique: finite difference method
computer code: Visual MODFLOW
Halil Önder
5. World Water Form Istanbul

15. Conclusions
severe shortage of fresh water supply is being and will be experienced
scarcity of water will result in insufficient food supply and undesirable health problems
underground dams are
environment friendly technology
socially acceptable
economically efficient
hydro geologically sound
ıntelligent tool and innovative approache to enhance the sustainability of groundwater resources
positive impact on the wellfare of small communities
Halil Önder
5. World Water Form Istanbul

16. Thank You for your patience
Small is beautiful:a study of economics as if people mattered
E. F. Schumacher. 1973
Make everything as simple as possible, but not simpler.
Albert Einstein
Halil Önder
5. World Water Form Istanbul