Medieval Dutch Hydraulic Engineering

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STS 3700 Lecture 3 – Water Management Technologies Through the Ages
Medieval Dutch Hydraulic Engineering
- European rainfall, thick, wet soil, iron–shod plough and oxen
- Field rotation, crop, fallow, manure, population increase
- Horse-collar, increased horse population, cavalry, stirrups
Hydraulic Engineering in Holland
- Limited land for farming, starvation, disease and warfare
- Holland below sea level, hydraulic engineering to create farmland
- Drainage of marshland using canals
- Reciprocal effect: draining one area led to flooding in another, draining led to
lowering of land further below sea level
- Simple technological developments and unexpected consequences
Coordination and Control
- 13th century: dikes (embankments to hold in water), dams (blocking rivers),
sluices (canal with gates), and drainage canals
- 1100 and 1300 hundreds of dikes and dams
- Excluding external water meant more flooding
- Polders: units of land at the same water level with shared drainage system, labor
and capital intensive
- System of autonomous water boards, predated government
- No central co-ordination, taxes and public works local
- The water boards were responsible for: regular inspection of facilities,
recommending repair, supervising and organizing labour and materials, collecting
taxes, dispute resolution
- Management of problem, hydrological hypothesis, unintended consequences,
technological fix, environmental changes
Flood Management in the Colonial Context
- Flood management for agricultural and damage prevention
- Did containment control or magnify damage?
Managing British Colonial Holdings
- Floods in the Orissa Delta in Colonial India
- Flood control embankments, flooding, cheap and easy to build
- Colonel Arthur Cotton, canals to control the river, irrigate, commerce
- Economic concerns, Indian Empire transferred to crown ownership (1858),
private capital was investing in transport networks
- Canals better than railways, equal investment, investment guarantees
- Investors and specialist authority on canals
- System slow to develop, under-utilized, government takeover in 1868
- Many irrigators did not use system, rate reductions, distinguishing between
licensed and unlicensed areas, rate collection
- Difficulties collecting rents
- Rainfall collection and traditional irrigation methods
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Laws against bunds, “small embankments created by cultivators to trap water
from drainage lines”
Forms of water capture: ponds, tanks and drainage canals
Government forced use of canal system rather than local sources
Owners rate for land was to be increased when irrigation was added
Embankments prevented smaller scale flooding, which brought fertilizing silt
Canal problems: higher elevations could not take on canal water, lower regions
became waterlogged
Determining fees for flood protection difficult
Flooding had benefits, making it hard to charge for flood protection
Summary
- The British government encountered several problems when attempting to deal
with the periodic flooding of the delta:
- Dilemma similar to the Dutch, river control for revenue, land tenure and
trade, but control led to more flooding
- Making nature legible or measurable in order to commodify it was
problem
- Colonial authorities, commercial and environmental goals, the impact of
flooding on “…rent assesses and landed taxpayers”
- Duration of committment
- Their system neither stemmed the floods nor improved agriculture
- Hardships for the irrigators (costs, crops)
Modern Hydroelectric Power
- Canada 60% hydro, 90GW capacity, third largest hydroelectric energy producer
in the world (behind China and Brazil)
- Norway almost 100% hydro
- James Bay Project: series of hydroelectric dams on the La Grande River in
Quebec, diversion of rivers
- Damming rivers creates reservoirs, individual La Grande complex reservoirs over
1000 km2 in size, some dams as tall as 50 stories
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North of Quebec, populations sparse, industrialization non-existent, native
hunting and fishing prominent
Facility generates approximately 15,000 megawatts = 16 CANDU reactors
Quebec electricity system provides approximately 35,000MW, 90% + hydro
20 billion to build complex
Initial resistance, settlements to Cree and Inuit populations
1975 agreement with Cree and Inuit, cash settlement, fishing and hunting rights
Extensive environmental consultation and analyses, scientifically informed
management of nature on a large scale
“Green” project, carbon neutral and thus not a contributor to global warming
Formal approval of native Canadian populations
Changing Nature
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-
Environmental concerns secondary to maximizing efficiency and power
generation
Flooding destroyed a wide variety of plant and animal life (beaver, muskrat, hare,
otter, birds)
Destroyed hunting areas used for thousands of years. 83,000 km of shoreline
Reservoir drops in winter (high demand), rises in summer (demand low)
Dead trees, fluctuating levels of water, large lifeless zone around reservoir
Tributaries diverted to increase La Grande River flow drop in level, eliminating
species such as sturgeon, muskrat and beaver
Heavy erosion of the banks of the La Grande
Millions of trees planted for reforestation and erosion reduction, small portion of
total facility
1977 environmentalists and ecologists hired, approach cosmetic (moving around
topsoil) or simply a technological fix (sills, smaller dams to raise local water
level)
For example, rather than clear timber before flooding, dead trees were harvested
and burned in a floating incinerator
45 biologists (in house scientists) completed survey of area
Species adaptation: caribou radiotagged, new calving grounds and migration
Animal culling
Management of water flow, fiscal and productivity concerns
1984 redirection of water in system combined with heavy rains to lead to a herd
of 10,000 caribou drowning
Narrow interests, blind to potential impacts
Scott: large scale management to maximize productivity leaves out local
information with various costs and consequences
McCutcheon: changing physical environment unpredictable despite use of science
Fish populations shifted, cold lakes and shallow river species increased in number
Reduction in biodiversity
Unintended consequence: increase in levels of poisonous methylmercury
Mercury in food chain, concentrated in species higher up the chain
Native populations and health risks from fish consumption
Changing native fishing patterns (social fix)
Is Hydroelectric Power “Green”?
- Project claimed to be environmentally sound, millions spent on studies
- Science determines impact, does not change direction, scale or management,
environmental concerns secondary to profit and productivity
- Northern ecosystems appear to be adaptable to change
o it takes time for the full impacts to be felt
o no independent data on the ecosystem before the project
- Major changes in land and its use, population levels
 Overall reduction in biodiversity
 Maximizing power output versus minimizing environmental impact,
adaptation of ecosystem
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