This document discusses insights into dam sustainability from economic, environmental, and social perspectives. It notes that over 85,000 dams in the US have an average age of 51 years and many are deficient or at high risk of failure. Dams provide economic benefits like power generation, water supply, and flood prevention but also have environmental impacts such as altering downstream flows and sediment transport. Socially, dams can displace local communities and impact health while also providing new infrastructure and jobs. The document recommends investing in maintenance of existing dams in developed nations and ensuring all stakeholders are involved and impacts are well-defined for new dams in developing areas.

1. INSIGHTS INTO DAM
SUSTAINABILITY
ECONOMIC, ENVIRONMENTAL, AND
SOCIAL

2. Introduction
Lake Dehli Dam,

3. Dam Failure
Lake Dehli Dam

4. 2009 ASCE Infrastructure Report
Card
 State of US Dams
> 85,000 in US
 Average age = 51 years
 G.P.A = D (Poor)
 4,000 deficient and 1,819 high hazard potential
dams
 Unsafe and failure could lead to catastrophic results
 Solutions
 $2.2trillion over 5 years for all infrastructure
 Promote sustainability

5. Pillars of Sustainability
 Brundtland Report
 Development that meets the needs of the present
without compromising the ability of future generations
to meet their own needs
 Economic
 Power generation, Water supply, Flood prevention
 Environmental
 Fish kills, Habitat loss, Nutrient Transport,
 Social
 New infrastructure, Displacement of locals, Health
issues

6. Economic - Common Purposes
 Power Generation
 Water Supply
 Irrigation
 Flood Prevention
 Land Reclamation

7. Hydroelectric Power
Dam Cross-

8. Hydroelectric power
 Major Reason for Construction of Large Dams
 Considered cheap and clean; An important
renewable energy source
 Large portion of US and World Energy
production
 An important part of local economies.

9. As Energy Source in the World

10. As Energy Source in US

11. Comparison: Other Energy
Sources

12. Part of Renewable Energy

13. Water Supply
 Important part of water supply infrastructure
 Used to store water for use during drier parts
of the year.
 Can be part of the water treatment process
Bill Young
Reservoir,
Tampa
Bay

14. Irrigation
 Agriculture is a main user of reservoir stored
water.
 Large dams often built to divert water from a
river toward dry or desert areas for farmland.
 Mixed Economic success
 Example: Rivers that feed Aral sea diverted in an
attempt to grow rice, melons, cereals, and cotton.

15. Irrigation
Aral Sea,
Central
Asia

16. Flood Prevention
 Attenuating or balancing Reservoirs
 Collect water during high rainfall and release it
slowly over the following weeks or months.
 Control of Nile river floods is a prime example
Aswan
High Dam
on the
Nile

17. Land Reclamation
 Dams can be built to hold back water for the
purposes of land development
 Known as Dykes or Levees.
 Prime examples:
 New Orleans
 Netherlands
Levee,
Netherlands

18. Economic Dangers
 Dams/reservoirs susceptible to droughts and
climate change.
 Examples:
 2001 Northwest drought reduced hydroelectric power
leading to loss of thousands of jobs in the aluminum
industry
 Columbia river reservoirs can only store 30% of
annual flow. Earlier snow melts means water is
released too soon for use by customers.
 Drought in the US west is causing Water Managers to
limit water withdrawals, to the detriment of local
economies.

19. Environmental - Reservoir
 Scale
 In the U.S, dams are capable of
storing the equivalent of an
entire year of runoff
 Submerged vegetation
 Decomposition by
microorganisms
 Nutrient release- initial increase
in productivity, potential for
anoxic conditions in benthic
areas
 Fish kills- result of seasonal
Hume reservoir in Albury, mixing of anoxic benthic water
Australia  Greenhouse gases- reduction of
sequestration, carbon dioxide
and methane release equal to

20. Surrounding Area
 Hydrologic cycle
 Standing water leads to a
temperature increase
 Alteration of evaporation
and precipitation
 Initial flooding
 Habitat loss and temporary
increase in mortality rates of
wildlife
 Mixed effects on local
wildlife
 Species specific effects
dependent on adjustment to Shasta Dam reservoir in
newly formed ecotone- California
benefits species such as
waterfowl

21. Downstream
 Flow regime
 Maintenance of natural
variability levels underlies the
productivity of downstream
ecosystems
 Dams often seek to reduce
flow variability, sacrificing
ecological functions
 Ecological functions include
matter and nutrient cycling,
providing critical habitat areas,
and nutrient deposit and
transport
 Adverse effects on highly
productive estuarine river
deltas, as conditions such as
salinity are dependent upon
river inputs. Ex- decline of the
Colorado delta clam

22. Downstream
 Sediment
 Lost to downstream
ecosystems through river
impoundments and diversions
 Removal of nutrients in
downstream leads to
decreased productivity in both
rivers and connected
ecosystems
 Loss of soil fertility on
floodplain. Ex- Aswan Dam in
the Nile Valley
 Direct effects on biota
 Physical barrier to migration
routes
 Can prevent access to critical John Day Dam Fish
breeding Ladder, Columbia
 Proposed solutions such as fish River
ladders

23. Social
 Benefits
 Roads
 Jobs
 Adverse Effects
 Displacement
 Health Issue
 Very seldom do they
experience the
economic and power
generation benefits

24. Effects due to Globalization
 Benefits are often not experienced by those
who were adversely effected by dam
construction
 Dams are generally constructed in rural areas
were they produce electricity and move the
electricity long distances to neighboring
industrial areas or cities
 The people in the dam region experience
temporary jobs, new infrastructure, and
relocation

25. Displacement
Project Country Number of  40 millions
Resettlers people
Three Gorges China 1,250,000 displaced in
Upper Krishna II India 220,000 the last 10
Sardar Sarovar India 127,000
years
Aswan High Dam Egypt 100,000  Compensati
Kossou Ivory Coast 85,000
on for
Longtan China 73,000
displacemen
t
Mahaweli I-IV Sri-Lanka 60,000
Kariba Zambia and 57,000
 River
Zimbabwe degradation
Sbradhino Brazil 55,000
effects on
community
Note: In a ranked table based on the number of resettlers,
the top 10 dams would be in China and India.
Source: Based on Scudder (1997a).

26. Compensation
 Lesotho Highlands Water Project
 One of the five largest dam projects in the world
 Brought infrastructure, roads and some employment
to a previously very rural and poor area of Lesotho
 A world class compensation plan was put in place for
those how resettled
 The difficultly with compensation is often
quantifying costs
 Compensation is often rebuilding houses
 More difficult compensation is finding displaced
families viable areas of lands for crops they
previously grew.

27. Health Concerns
 Reservoir is a perfect habitat for vectors
 Vectors,such as mosquitoes and snails, bring
diseases
 Diseases include Malaria and encephalitis
 Due to displacement families are driven to
consume unsafe water
 Resettled groups live in a denser populated
area resulting in poor hygiene and host of
other diseases

28. Health Impacts
Impact Area Effect of Dam Health Impact
Upstream Loss of biodiversity, increased agriculture, Changes in flood security, water related
catchment sedimentation and flooding, changes in river flow diseases, difficulties with transportation and
and river regime. access to health facilities
Reservoir Inundation of land, presence of large manmade Involuntary resettlement, social disruption,
area reservoir, pollution, changes in mineral content, vector-borne diseases, reservoir induced
decaying organic material seismicity
Downstream Lower water levels, poor water quality, lack of Food security affected on flood plains and
river seasonal variation, loss of biodiversity estuaries (farming and fishing), water-related
diseases, dam
failure and flooding
Irrigation Increased water availability and agriculture, water Changes in food security, vector-borne and water
areas weeds, changes in flow and mineral content, related diseases
pollution
Construction Migration, informal settlement, road traffic Water-related diseases, accidents and
activities increase, hazardous construction occupational injuries
Resettlement Social disruption, pollution, pressure on natural Communicable diseases, violence and injury,
areas resources water
related disease, loss of food security
Country/regio Reduced fuel imports, improved exports, loss of Macro-economic impacts on health, inequitable
nal/global biodiversity, reallocation of funding, sustainability allocation of revenue, health impacts of climate

29. Conclusions
Economic
 Global electricity consumption
 Fossil fuels – 69%, Nuclear – 13%, Hydropower
– 15%, Other renewables – 3%
 Hydropower – Relatively low & constant prices
 Water Supply – Drinking and agricultural
irrigation
 Flood control and land reclamation

30. Conclusions
Environmental
 Reservoir - Greenhouse gas emissions, Fish
kills
 Surrounding Area – Habitat loss
 Downstream – Altered flow, Sediment
deposition
Social
 Benefits – Jobs, New infrastructure
 Adverse effects – River degradation, Health
problems

31. Recommendations
 Developed World (United States)
 Most suitable locations have already been built
up
 Only way to improve sustainability is by investing
in maintenance to extend their lifespans
 Developing World
 The impacts must be well defined
 All stakeholders must be involved in the
discussion
 Mechanisms must be in place to regulate
operations

32. Thank you
Hoover Question
Dam, s?
Nevada