Water Properties, Circulation, and Resources Management

Posted on Dec 9, 2024 in Geology

Importance of Water for People, Industry, Agriculture, Ecosystems, Recreation, and Landscape

• The human body is comprised of approximately 80% water.
• A loss of 12% of body water can result in death.
• The minimum amount of water required, depending on climate, is 2-7 liters per day.
• Average water consumption for domestic purposes is 135-150 liters per day.
• In developed countries, it is 500 liters per day per person.

Functions of Water:

• Domestic and municipal purposes
• Navigation of rivers and channels
• Industrial processes (cooling)
• Agriculture (irrigation)
• Hydroenergy
• Recreation and sport
• Support for aquatic flora and fauna (all aquatic ecosystems)
• Landscapes aspect
• Good solvent
• Storage of huge amounts of energy
• Cause of Earth’s erosion
• Transports sediments in rivers

Basic Properties of Water: Density, Viscosity, Specific Heat, Latent Heat

Density [ρ]- The density of a material is defined as its mass per unit volume; [m/V]. The basic factor that influences the density of inland waters is water temperature. The relationship between water temperature and density is unique and cannot be found in any other liquid. Water reaches its highest density of 1000 g/l at a temperature of 4°C. From that value, independently of whether the temperature is rising or falling, the density decreases. Changes in water density result in changes in water volume with water temperature. Salinity has a great impact on water density; basically, with the rise of salinity, density increases, which is of great importance in coastal waters where salty seawater mixes with river water.

Viscosity (dynamic[μ]; kinematic[ν] ν=μ/ρ) – The viscosity of a liquid is a measure of its resistance to flow. The viscosity of water decreases with water temperature.

Surface tension[σ] – It is the energy needed to create the free surface (work must be done to bring molecules to the surface of the liquid); [N/m]. The force is always normal to the surface. That is why drops of water always get a spherical shape, why we can place a needle on the water surface, and why some insects may move over the water surface. Surface tension decreases with water temperature.

Specific heat [C_p] – It is the energy needed to raise the temperature of 1 kg of fluid by 1 K. For water at 20 °C, it is equal to 4.18 [kJ/ (kg*K)]. It changes slightly with water temperature.

Latent heat of vaporization [C_e] – The heat needed for vaporization and released in the condensation of a liquid. In the case of water at 20°C, C_e=2454 [kJ/kg]; this number is higher for sublimation and resublimation, respectively, and is equal to C_e=2837 [kJ/kg], as it is a double-step action. It changes slightly with water temperature.

Latent heat of freezing/fusion [C_f] – It is the heat needed for ice to melt and released by water when freezing. It is of great importance because when water is changed to ice, its volume expands considerably. Ice density at 0°C is 917 kg/m³, and so it floats on the water surface, which enables aquatic organisms to live during winters.

Physical Processes Governing Water Circulation and the Water Cycle

1. Solar radiation (heat energy which causes evaporation 505ּ10³ km³/year)

2. Gravitation (force which causes movement down to the Earth’s surface)

Solar radiation ® evaporation from oceans and land ® transport in the form of vapor in the atmosphere ® condensation ® precipitation over land and oceans ® surface runoff and infiltration ® overland, subsurface, and groundwater flow (but also it may be retained by vegetation, snow, glaciers) ® surface and groundwater outflow into oceans

Main Results/Functions of Water Circulation

1. Purification, as evaporating water leaves pollution in the original reservoir

2. Air conditioning system, which causes moderation of climate through latent heat of fusion and evaporation

3. Supply of fresh water to rivers

Laminar and Turbulent Flow, Reynolds Number, Froude Number

Laminar flow – A type of flow that is characterized by smooth flow lines where only shear stresses are acting. In that case, the flow is well-ordered, and every fluid particle moves along a straight path parallel to the rigid boundary. The maximum velocity is twice as high as the mean velocity, and velocity distribution is regular. Re < 2000

Turbulent flow – Does not have smooth flow lines at all. It is characterized by the formation of eddies within the flow, resulting in continuous mixing throughout the channel or pipe cross-section. Flow velocity is close to the mean velocity. Re > 4000

Reynolds number [Re] – Is a dimensionless number that gives a measure of the ratio of inertial forces to viscous forces and, consequently, it quantifies the relative importance of these two types of forces for given flow conditions. For Re between 2000 and 4000, the flow is transitional and can be either laminar or turbulent.

Closed channel flow – Re=VD/ν; where V is the average velocity in the pipe [m/s], D is the inner pipe diameter [m], and ν is the coefficient of kinematic viscosity [m²/s].

Open channel flow – Re= V4R/ν; where V is the average velocity in the pipe [m/s], R is the hydraulic radius [ratio of flow surface to wetted perimeter], and ν is the coefficient of kinematic viscosity [m²/s].

Froude number [Fr] – Is a dimensionless number comparing inertial and gravitational forces, showing the effect of gravity upon the state of flow. Fr=1, flow is critical, very unstable. Fr<1, flow is subcritical, large depth, small velocity, preferred in engineering practice. Fr>1, flow is supercritical, small depth, large velocity. Fr = V/√(gR); where V is the mean velocity, g is gravity, and R is the hydraulic radius.

Open Channel Flow

Open channel flow is a flow which has a free surface, subject to atmospheric pressure. It is characterized by flow area A, wetted perimeter P, and width of free surface B. From those values, hydraulic radius R and average depth D can be calculated: R=A/P; D=A/B. Discharge Q=V*A

Manning formula – A formula used to estimate the mean velocity of flow in open channels. The Manning roughness coefficient n is assumed to be constant over the full range of flows and water depths in a given cross-section. It has been experimentally determined for various types of materials. V= 1/n*R^2/3*S^1/2, where n is the Manning roughness coefficient, R is the hydraulic radius, and S is the slope of the channel.

Closed Flow

The flow in pipes is often called pressure flow, as water in the pipes fills its cross-section and is under pressure. In many cases, such as water hammer, the compressibility of water must be taken into account.

Head loss – Generally speaking, it is the loss of energy per length of pipe. DARCY FORMULA H_L=f*L*V²/(D*2g); where f is the friction factor, L is the length of pipe, V is the average flow velocity, D is the inner pipe diameter, and g is gravity. H_L/L=S, S is the slope of the hydraulic grade line. The mean flow velocity equation is V=√(8g/f)*√(RS). ε=k/D, where ε is the relative roughness, k is the roughness height, and D is the inner pipe diameter.

Groundwater

It is 30% of the total fresh water. It supplies rivers and streams during periods without precipitation or drought. Underground flow is very slow because of high flow resistance. Small velocity and small dimensions of channels result in laminar flow. For laminar flow, Re<5 [Re=VD/ν]. Head loss=1/kVL, but as real flow velocity and length of channel are really difficult to specify, we substitute real flow with filtration flow. We assume that the flow takes place through the whole cross-section and not only in channels between soil particles. Thus, filtration velocity will be much smaller than real velocity between particles. For filtration velocity, we use Re>5.

Darcy formula: V=kI, where V is the filtration velocity, k is the filtration coefficient (done in the laboratory or in situ), and I is the gradient of the hydraulic grade line.

Infiltration as a flow of water from precipitation into the ground may result in subsurface flow in the unsaturated zone (above the water table) and groundwater flow in the saturated zone (below the water table), which outflows directly to the water reservoir. To calculate the inflow q to the ditch: q= k/2L*(H²-h²); where k is the filtration coefficient, L is the length from the edge of the bottom till the ‘shore’ of the ditch, H is the height from the impermeable layer to the water surface, and h is the height from the impermeable layer to the bottom of the ditch.

A well is always considered to be circular and reaching the impermeable layer. For calculating its groundwater inflow, we use: Q=π*k*[(H²-h²)/ln((R/r)]; where k is the filtration coefficient, H is the height from the impermeable layer to the water surface, h is the water depth in the well, R is the distance from the center of the well to the point where the depression of the water table crosses the original water table (can be calculated from R=3000(H-h)√k), and r is the radius of the well.

Precipitation, Evaporation, Runoff, Retention, Water Balance

Precipitation

1. It is the main source of water supply to the Earth.
2. Liquid form (rain), stable form (snow, hail).
3. In Poland, there are 1500 stations for precipitation measurements.
4. The data are presented in mm of water layer and are standard for hydrological measurements.
5. Normal precipitation is the average value from 30 years.
6. Data are shown mainly in the form of a histogram.
7. The lowest precipitation is in the lowland Kujawsko-Wielkopolskie, and the highest is in the Tatra Mountains.
8. The Polish climate is qualified as slightly humid.
9. The amount of precipitation increases with elevation to a certain level (in Poland, 1500m), and later, there is an inverse trend.

Precipitation intensity – Millimeters per minute/hour.

Volume of precipitation – The total amount of water which falls on a given area during a certain period of time. It is the product of precipitation height [m] and the area [km²], volume given in m³.

Effective precipitation – The part of the total precipitation that flows over the surface of the ground (called runoff) and forms open channel flow.

Retention/Interception

1. The physical process of holding water for some time on the Earth’s surface.
2. Forms: snow, ice, Earth’s surface, lakes, river channels, flood plains, marshes, ground, and retention reservoirs.
3. Important in flood protection.

Evaporation

1. Takes place at every temperature.
2. From free water surface.
3. From ice and snow (sublimation).
4. Evaporation from the ground.
5. Transpiration.
6. It moderates the climate and protects plants and animals against excessive heat.
7. Its intensity depends on air humidity (if it rises, evaporation decreases), temperature, and wind (if they rise, evaporation rises).

Runoff – Water from precipitation or melting snow initially flows over the ground. This type of flow is called runoff. It lasts a relatively short time, as water evaporates, infiltrates into the ground, or finds its way to streams, brooks, ditches, and rivers.

Outflow

1. The amount of water which flows out from a given area, usually a catchment, during a specific period of time.
2. Unit outflow q – The amount of water which flows from a given catchment through the measuring cross-section during a determined period of time, divided by the catchment area [l/(s*km²)].
3. The outflow coefficient is the ratio between outflow and precipitation.

Water balance

P=H+E+ΔR; where P is precipitation, H is river outflow, E is evaporation, and ΔR is the change in retention.

1. Everything in m³ or mm.
2. Annual water balance usually concerns the hydrological year, which begins on November 1^st and lasts till October 31^st. Such an assumption minimizes the amount of retention, which is hard to define.

River Catchment

River catchment (basin) is the area of land from which all surface runoff flows through a sequence of streams, rivers, and possibly lakes into the sea at a single river mouth, estuary, or delta.

River basin district – The area of land and sea made up of one or more neighboring river basins, together with their associated groundwater and coastal waters, which is identified as the main unit for the management of river basins. At present, according to Polish law, the whole area of Poland is divided into 10 River Basin Districts, the two main ones being Vistula and Odra.

Floods: Types, Flood Protection, EU Flood Directive

Floods are natural hydrological phenomena which appear in the hydrological cycle. It means an increase in water elevation or discharge in the river, which results in economic, social, and ecological losses, even loss of human life.

Types of floods:

1. According to their appearance:

1.1 Caused by various types of precipitation – On small areas, very intensive, usually short-lasting precipitation (flash floods). Frequent in urban areas, e.g., Gdańsk, July 2001. Another sub-type is caused by long-lasting rain over large river catchment areas. Poland ’97 – along the Odra and upper Vistula.

1.2 Caused by ice and snow melting – In spring, higher temperatures plus rain, rapid melting of snow and ice. The soil is still frozen and can’t accept infiltration, leading to direct, rapid water flow (run-off) to rivers.

1.3 Ice jam – At the beginning of winter, ice covers form, and in spring, ice breaks up, and ice runs take place, caused by a flow obstacle in the form of ice in a river channel. At the beginning of winter, formation of frazil ice – small ice crystals – caused by supercooling – later formation of agglomerates – ice floats in the form of ice pancake ice. Can clog water intakes and trash racks of power plants.

1.4 Storm – In coastal areas, caused by the increase of water elevation in the sea, also an increase in discharge in rivers. Connected with high tide.

1.5 Anthropogenic – By unintentional human activity, engineering errors.

2. According to the area which is influenced:

2.1 Flash floods – Appear very rapidly, have extreme run, small areas.

2.2 Regional floods – Larger areas, several days, even weeks.

Flood protection:

1. Retention reservoir – Stores water for future use (e.g., domestic, industrial purposes). Multipurpose reservoirs – part of the water from floods is stored.

2. Dry reservoir – Decreases water discharge, detains water, and later releases it to the river. Built in the upstream part of rivers and streams, mainly in mountains.

3. Polders – Have the same function as a dry reservoir, created along a river on both sides. Areas surrounded by embankments, into which flood water from the rivers is discharged by means of side spillways which are placed on the bank of the river.

4. Forecasting system: Meteorological radars – Allow forecasting several hours in advance the area of precipitation and its intensity. Automatic pluviometers provide early information about accrual precipitation, confirming the previous assessment of the meteorological radar. The next step is gauges recording water stages. These three things give numerical flood forecasting, which needs good analysis.

5. Flood education

Drought: Characteristics and Consequences

1. Drought – A period when water demands by society in all sectors exceed the capacity of the natural system as a result of (or a combination of):

2. Meteorological factors (rainfall deficiency, air temperature, and humidity).

3. Agricultural factors (availability of soil water during the vegetation season is a critical factor).

4. Hydrological factors (flows in rivers decrease and the water table decreases).

Consequences:

1. In agriculture, low production of vegetables.

2. Forest fires.

3. Trees attacked by pests.

4. Tourism – people stay at home.

5. Lower energy production – nuclear power plants don’t have enough water.

6. Water supply – decline of surface and groundwater resources.

7. Biodiversity – animals are exposed to harsh conditions, fish die.

8. Heat stress – death of people.

Rivers: Characteristics, Flow, Sediment, Heat, Pollutant Transport

A river is a natural stream of water, usually freshwater, flowing toward an ocean, a lake, or another stream. In some cases, a river flows into the ground or dries up completely before reaching another body of water. Usually, larger streams are called rivers, while smaller streams are called creeks, brooks, rivulets, rills, and many other terms, but there is no general rule that defines what can be called a river. Sometimes a river is said to be larger than a creek, but this is not always the case. A river is a component of the hydrological cycle. The water within a river is generally collected from precipitation through surface runoff, groundwater recharge (as seen at baseflow conditions / during periods of lack of precipitation), and the release of stored water in natural reservoirs, such as a glacier.

River flow – Conveyance of a certain amount of water through a river cross-section, called the discharge of river flow [m³/s]. The amount of water which flows through a given cross-section during a certain period of time is outflow [m³].

Sediment transport – Bed load (coarse sediment) moves over the bottom of the river [mass unit per second and meter width of river], and suspended sediments (fine material) move in suspension due to the flow turbulence – the amount of sediment to the volume of water.

Heat transport

Pollutant transport

Rating curve – An empirical relation between water stage [H] and discharge [Q – m³/s].

Hydraulic Structures: Dams, Weirs, Locks, Reservoirs, Training Works

Dams (embankment and earth-fill) have highly stable and small movable gates, whereas in weirs, small movable parts predominate; therefore, they are combined with other hydraulic structures, forming barrages (Włocławek: navigation lock, hydraulic power plant, weir, fish pass, earth dam). They retain water in reservoirs by means of impounding a river or stream, which enables the distribution of water evenly in rivers downstream, providing flood protection, domestic, agricultural, industrial, recreational, navigational, fishery, hydraulic power plants, and irrigation.

Navigation locks – Concentrated heads on rivers and canals. Aim – to transfer ships and barges from high to low water elevation and vice versa. Construction: lock chamber, lock gates, valves, filling & emptying systems.

Culverts – Crossing of small rivers, streams, and ditches with the road, conveying water underneath the road.

Training works – Stabilize river or stream channels, done by groins – constructions which extend perpendicular to the shore into the river channel. They can also be built by longitudinal dams protecting the shore against erosion.

Fish passages and ladders – To facilitate the movement of migrating fish.

Reservoirs – A reservoir refers to an artificial lake used to store water for various uses.

Natural – Lakes, ponds, water surface elevation controlled by the hydrological cycle. Parameters: total volume indicated [m³], surface area at a normal water surface elevation [ha], maximum and minimum water surface elevation [m], average inflow and outflow [m³/s], residence time in hours, days, months, years.

Artificial – Development of hydraulic structures on rivers. Aim – to store water when there is too much and use it when there is too little. Parameters: maximum water surface elevation, residence time for average total reservoir volume, range of water surface fluctuation, operational volume, dead volume, maximum and minimum inflow, maximum discharge through spillway, minimum outflow discharge, and maximum permissible discharge.

Hydropower Plants: Advantages, Disadvantages, Efficiency

Advantages:

• Flood protection.
• Renewable energy is ecologically clean, without air pollution.
• Recreational possibilities on reservoirs formed by dams.
• The cost of fuel is practically avoided.
• Can be switched on or off within seconds, depending on demand.
• Efficiency is high in a wide load range (95% compared to 50% of fossil fuels).
• Employment increases and technological progress increases (turbines, generators).
• Economic development of developing countries that usually have high hydro-energy potential.
• Durable.

Disadvantages:

• Impoundment and formation of reservoirs have a negative ecological impact.
• Impoundment causes changes in river hydrodynamics, thermal regime, and migration of fish.
• Farm and forestland may be lost.
• The cost of construction is high.
• Corrosion of turbines in certain conditions.

Differences between pumped-storage and regular hydropower plants:

A pumped-storage plant is a special hydraulic power plant that consists of two reservoirs, upper and lower, connected by penstocks to the power plant. During off-peak time (when an excess of energy exists), water is pumped from the lower to the upper reservoir -> potential energy is stored in the upper reservoir. In peak hours, water is directed via turbines to the lower reservoir -> electric energy is produced. Efficiency is around 70%. The efficiency of a regular hydraulic power plant is around 92%.

Hydroelectricity is electricity generated by hydropower, i.e., the production of power through the use of the gravitational force of falling or flowing water. It is the most widely used form of renewable energy. Once a hydroelectric complex is constructed, the project produces no direct waste and has a considerably different output level of the greenhouse gas carbon dioxide (CO₂) than fossil fuel-powered energy plants. Worldwide, hydroelectricity supplied an estimated 715,000 MW in 2005. This was approximately 19% of the world’s electricity (up from 16% in 2003) and accounted for over 63% of electricity from renewable sources. Most hydroelectric power comes from the potential energy of dammed water driving a water turbine and generator. In this case, the energy extracted from the water depends on the volume and on the difference in height between the source and the water’s outflow. This height difference is called the head. The amount of potential energy in water is proportional to the head. To obtain a very high head, water for a hydraulic turbine may be run through a large pipe called a penstock. Pumped-storage hydroelectricity produces electricity to supply high peak demands by moving water between reservoirs at different elevations. At times of low electrical demand, excess generation capacity is used to pump water into the higher reservoir. When there is higher demand, water is released back into the lower reservoir through a turbine. Pumped-storage schemes currently provide the only commercially important means of large-scale grid energy storage and improve the daily load factor of the generation system. Hydroelectric plants with no reservoir capacity are called run-of-the-river plants since it is not then possible to store water.

Water Demand and Supply

Water Demand: The amount of water that a water user actually applies to a beneficial use, within the terms of his or her water right and applicable law.

Water supply is the process of self-provision or provision by third parties in the water industry, commonly a public utility, of water resources of various qualities to different users. It also means the water available for a community or region. Water supply comes from precipitation, rivers, lakes, reservoirs, or groundwater.

Sustainable Development and Environmental Impact Assessment

Sustainable development by the Bruntland Commission: Sustainable development ensures and meets the needs of the present without compromising the ability of future generations to meet their own needs.

Water resources management projects are sustainable if water of sufficient quality, quantity, and acceptable prices is available to meet the demands of the present and future without causing a negative impact on the environment (EIA should be made for engineers and”laik”).

• Effect on hydrological, thermal, and chemical regimes.
• Effect on the ecosystem now and in the future.
• Effect on people.
• Assessment of alternative solutions.
• Assessment during construction, operation, and after (possible effect at end-life).
• Influence of a new hydraulic structure on the environment when the hydraulic structure will end its active life.

Tendencies:

• All decisions must be agreed upon with the general society.
• All new instruments must be secure technically, economically, socially, and ecologically.
• Monitoring of new and existing projects.
• New projects should interfere minimally with the environment.

Integrated Water Resources Management

Management that takes under consideration all sociological, economical, ecological, and spatial arrangement aspects (awareness, benefits, droughts/floods, surface/ground/coastal waters).

Water Resources Systems

• Sewage treatment plant.
• Hydraulic structure for water management (dam, weir).
• Hydraulic structure for water conveyance (pipeline).
• Natural water body (river, lake).
• Enterprise using water (hydraulic power plant, fish pond).
• Discharge structure to the natural body.

Administration of Water Resources in Poland

The territory of Poland is divided into seven Regional Boards of Water Resources Management (RBWRM): Warsaw, Krakow, Gliwice, Wroclaw, Poznan, Szczecin, and Gdansk. The RBWRMs are the basic units of water administration, each one of them has defined duties from Article 92 of the Water Law. Each area has its specific character, e.g., Gdansk and Szczecin deal with inland waters, coastal and transitional waters. Krakow, Wroclaw, and Gliwice cover mountain areas where high precipitation might result in flash floods. On the other hand, Warsaw and Poznan deal with areas where the precipitation is very low, thus might cause drought.

Polish Water Law, EU Water Framework Directive

When Poland entered the EU, the water regulations had to be adjusted to the EU ones, mainly the Water Framework Directive. On June 3, 2005, Parliament introduced several amendments to the Polish water law. A lot of articles were removed, and new ones were introduced. Main amendments concerned the division of the Polish territory into river basin districts (two main ones: Vistula and Odra). Another amendment introduced to the Polish Water Law two new definitions regarding the uniform system of water bodies (separate and important elements of surface waters which can appear as artificial and heavily modified) and uniform groundwater bodies (volume of groundwater which appears in an aquifer or several aquifers). Even after introducing these amendments, there are still several differences between EU and Polish water law, such as in Poland, we only distinguish river basins, while in the EU, there are river basins and sub-basins. The Polish water law is divided into 10 sections:

1. General principles
2. Use of water
3. Protection of water
4. Hydro-engineering contraction
5. Protection against floods and droughts
6. Management of water resources
7. Water companies and flood dyke societies
8. Responsibility for damages
9. Penalty regulations
10. Changes in binding regulations, temporary regulations, and final regulations

Important aspects of water law:

• Water resources management
• Sustainable development
• Integrated resources management

Main Aims of Water Resources Management

• Assuring there is enough amount of quality water for the population.
• Protecting the water against pollution and excessive exploitation.
• Maintaining the improvement of the water ecosystem and its surrounding ecosystems.
• Protection against floods and droughts.
• Securing water for the needs of agriculture and industry.
• Making sure there is enough water for tourism, sport, and recreation.
• Creating conditions for energy, transport, and fishery use of water.

High Aswan Dam

Length: 3830 m

Height: 111 m

Storage capacity : 162 km³

Hydropower station capacity: 10⁹ kWh per year

The Nile is the longest river in the world and has played a vital role in the history of Egypt. Aswan High Dam was built in 1964, and since then, it has been stated to be the largest construction since the times of the Pyramids. Before damming, the annual floods nourished local farming lands, but it also caused destruction and death to people. Building the Dam resulted in seizing the Nile’s forces and making them provide a regular water supply and 2.1 GW of electricity generated by 12 generators. Aswan’s hydropower has been successful in supplying its cheap electricity to industries. Up to three crops could be raised each year, and flood effects have been strictly controlled. The effects of two great droughts (1972 and 1983) as well as floods (1964 and 1973) were mitigated by the dam. Lake Nasser, that was created behind the dam, constitutes an important fishing resource and a nice place for leisure. However, there were unexpected costs of the dam:

1. Many people living near the dam had to be resettled without proper compensation. Many archaeological sites were destroyed or relocated, including the temple of Abul Simbel.

2. Silt has been trapped behind the dam wall. The rich silt is no longer available for the farmland. Farmers now have to add expensive chemical fertilizers to their land.

3. Irrigation channels have become the breeding ground for water-borne diseases.

4. It has been estimated that up to half of the water that flows into Lake Nasser (the reservoir behind the dam wall) is lost to evaporation and seepage into the groundwater.

5. Over-irrigation of the farming lands is causing salinity and waterlogging problems, making the land less productive.

From an industrial and governmental perspective, both dams were successes in their original goals (to control flooding, prevent drought, and supply hydroelectric power). From an environmental and humanitarian perspective, these dams altered ecosystems and displaced native peoples that had lived in harmony for literally tens of thousands of years. As with any major project, there is more than one side to the story, and humans continue to learn to predict the outcomes of their actions and the effects these new conditions create.

Three Gorges Dam

Location: on the Yangtze River

Length: 2,335 m

Height: 101 m from river level, 185 m from sea level

Width (at base): 115 m

Construction Cost: estimated 180 billion yuan (39 billion $)

Start of construction: 1994

End of construction:2008= 14 years of building/ Dam on the Yangtze River in China. The biggest dam in the world. Next are far after. Most controversial dam. The ecologists were against it because it involved repatriation thousands of people, flooding big territory, which were forests. The flooded forests start to rotten producing methane. So the positive impact of dam is neutralized by methane production in really big quantities even now. Dam reduce 30 million tons of coal per year. Dam is still being built (now passes 14 years of building). It was predicted to cover 10% of electricity but because of growth of economy it covers just 3%.  Dam will become fully functional till 2011. The Three Gorges Dam is the world’s largest hydroelectric power station by total capacity, which will be 22,500 MW. After completion, the expected annual electricity generation would be over 100 TWh, 18% more than originally predicted 84.7 TWh, since six more generators were added to the project in 2002. As of October 30/2008 the Three Gorges Dam Project had generated over 274.4 TWh of electricity, more than one fourth of the to generate to cover the cost. In the river lived very rare white dolphin – Benji which after building dam extinct. Environmental impact: /Lowering the quality of water/Detriments to wildlife/Riverbank collapses/Falling of coastal areas/Water:Even in the higher banks of Yangtze quality is decreasing/Slowly worsening due to the dam/Dispersing of pollutants is stopped/Fastened eutrophication/Algae and blue-green algae blooms/All these factors influence the quality of water 

 Flood in Gdańsk 2001 Possible sources of Flood:/From moraine hills because of intensive rainfall /From the Gulf of Gdańsk caused by strom surges/From the main channel of Vistula river in case of very high discharge or ice jam 9^th July 2001:4hrs/80mm precipitation /Daily amount of precipitation was 120mm/Urban flash flood coming from moraine hills /120m³/s over 4hrs into RCh /Right catchment (depression) flooded /Tot. Amount of water discharged was 1,7mln m^{3 /} 

Results: /5000 people received calamity status/Quick repair of RCh embankment /Pumping to drain flooded areas /Draining and drying of basements /Action to fix roads and remove sediments /Flood protection Project:/Infrastructure difficult to change /Consortium called into being ((measurements of GWN/hydraulic analysis /evelopment of 1D unsteady flow model/ proposal of technical solutions) /RCh catchment divided into subcatchments with 18 small retention reservoirs /3 additional outflows from RCh  to Motława and Radunia rivers….The project hasn’t been even started yet.

 Flood in Poland 1997 In the second half of June, the weather in Poland was shaped by cyclonic precipitation of high intensity and depth throughout the country, except in the northern and northwest parts. This precipitation filled much of the natural available water retention, saturating available soil storage:/Precipitation in July (4 – 10), the highest between 6 – 8, Kamienica 484mm, Międzygórze 455mm/Few day later (15 – 22 of July), the highest precipitation 17 – 22, drainage basin of rivers Bystrzyca and Kaczawa 150-300mm, Bóbr and Kwisa 150-200mm, Kłodzko valley 100-200mm Three phases of the 1997 flood can be distinguished:/ – the first phase was a runoff response after intensive rainfall in the upper Odra and its highland tributaries / – in the second phase a huge flood wave in the river channel of the Odra (Racibórz  with 65000 inhabitants, Opole with 131000 inhabitants and Wrocław with 700000 inhabitants were inundated / – Finally the third phase high water levels reached the border stretch of the Odra and the lower OdraConsequences:/54 fatalities /2592 towns and villages were flooded /46000 houses and apartments were domaged/162000 people were evacuated /66500 ha of land were flooded /480  bridges were destroyed  and 245 damaged /3000 km of roads and 2000 km of railway were destroyed /1900 cattle, 5900 bigs, 360 sheep, 1 million poutry were killed /Embankments of distance 1100 km were domaged /169  sewage treatment plants were domaged …Could the disaster have been avoided? Though it was the largest natural disaster in the 1000-year history of Poland, the disaster could not have been avoided. Thanks to the Czorszyn-Sromowce Wyżynne reservoir, it saved a lot of settlements and towns. There were plans that have never come to realization like Racibórz reservoir because of high costs , difficult task of relocation of inhabitants and attack of environmentalists.

 Inland navigation :/transport of goods/ecological,fuel saving,tourism, but high cost of infrastructure (increasing depth/1% in PL however good prospects; navigable routes 4000km, navigable rivers 3250km but onlu 1900km used for navigation

 Włocławek barrage :/navigation lock, hydraulic power plant, weir, fish pass, earth dam (length 600m)/tourism, electricity, fish development/errosion, impossible navigation

30. Czorsztyn dam and hydraulic power-plant Overall capacity of the  Czorsztyn- Niedzica reservoir: 231,9 mln m3 and its Maximum flood dam up level is 534,5 m, while the minimal dam up level is 510,0 m/Czorsztyn-Niedzica hydraulic power plant is situated on Dunajec River in Southern Poland, in Podkarpackie voivodship, Nowotarski powiat. Dunajec river is 14^th polish longest river, and has characteristic high and rapid fluctuations of water level (to 11m in lower stream), and supplies about 20% of water resources of upper Vistula./First mentions about building dam and power plant on Dunajec are from 1905, but their realization started after great flood in this region in 1934. The final start of operation of Czorsztyn- Niedzica power plant was in 1997. Main reservoir Czorsztyn-Niedzica was created by the closure of Dunajec river using the dam situated in the most favorable narrow part of the valley- Below the Castle Niedzica Hill./The fluid-flow, pumped-storage power plant gives the electric energy to the network during the highest demand periods (regulatory services for national energetic network). Pumping abilities are used during the night time, when the energy is cheap and it is a lot of it- water is pumped from the lower to upper reservoir- and is used next day to supply the turbines/The characteristic feature of pumped-storage p-p is its the short time of startup which in our case is 3-4 min./Plant consist of two turbo units of 90MW power during turbine regime, and 89MV during pumping regime. The turbine installed is the diagonal cross-section Derioz type one. This is a turbine with double regulation of runner blades and guide apparatus. It has a favorable characteristics, it works with profitable efficiency in wide spectrum of flows. Fluid-flow, pumped-storage power plant- which gives the electric energy to the network during the highest demand periods (regulatory services for national energetic network). Pumping abilities are used during the night time, when the energy is cheap and it is a lot of it- water is pumped from the lower to upper reservoir- and is used next day to supply the turbines. The characteristic feature of pumped-storage p-p is its the short time of startup which in our case is 3-4 min./The installations helped to protect the region against the flood in 1997 by reducing the flood wave from 1450 m3/s to about 600 m3/s outflow from Sromowce Wyżne reservoir./Apart from reducing the flood waves the advantages of this installation are increase of minimal flows, production of clean energy, hydro- meteorological protection system succor, sport& tourism on reservoir, increase employment and technical development as well as many other.

 Flood protection of St. Petersburg Neva River:/Origin – Lake Ladoga/Mouth – Gulf of Finland/Basin countries – Russia, Finland, Belarus/Length – 74 km /Avg. discharge – 2,600 m³/s/…In response to the threat of flooding, the Russian Government decided to construct a Flood Protection Barrier (FPB) across the Gulf of Finland. This Barrier comprises eleven rock and earth embankment dams, six water discharge sluices to accommodate outflow from the river Neva and two navigation channels equipped with closing gates. The Barrier also incorporates road bridges at each of the sluices, a road tunnel at the main navigation channel, a lift bridge at the secondary navigation channel and a road constructed on the embankment dams. The overall length of the Barrier is 25.4km. In 1978 the project was officially approved and two years later construction began. However, construction of the Barrier was suspended for over 15 years due to lack of funds and to environmental protests. In 2003 construction resumed and in 2005 it received a financial and technical boost It is believed that the President Vladimir Putin (native of St.Petersburg )  was involved in finding a solution. Thanks to the pressure at federal level, the project is now due for completion in 2008 (the protection) and 2012 (the highway) 

 Flood protection in Netherlands Zuiderzee Works:/Driving force: flood in 1918 /30 km dam enclosing North Sea inlet /165 000 hectares of gained land..Rotterdam is the second largest port in the world which is located about 30 miles due east of the North Sea, in the interior of the province of South Holland.   “Delta Works”- The Hollandse IJsell Storm Surge Barrier was first established in 1958. It separates Rotterdam from the North Sea and thus protects the densely populated western part of the Netherlands (Randstad). Storm surge barrier works by lowering two weirs or gates into the river   “Delta Works”- The Maeslant Storm Surge Barrier It is a flood control structure which was built between 1991 and 1997 in the mouth of the Nieuwe Waterweg  to stop storm surge from the North Sea. It is not necessary anymore to raise the dikes around Rotterdam. The Maeslant barrier consist of two steel doors which is sunk down and turned away in the docks in the shores. 

 Polish and European Rivers (Vistula, Oder, Danube, Rhine, Dniepr)VISTULA:Origin:  Barania Góra, Beskidy Mouth: Gdańsk Bay, Baltic Sea /Basin countries: Poland, Ukraine, Belarus, Slovakia /Length:1047 km /Source elevation: 1106 m /Avg. discharge: 1080 m³/s (at mouth) /Basin area: 194424 km²The Vistula is the longest river in Poland at 1,047 km. It has its source in the south of the country, at Barania Góra (1220 m high) in the Beskidy Mountains where it starts with the White Little Vistula (Biała Wisełka) and the Black Little Vistula (Czarna Wisełka)./It then continues to flow over the vast Polish plains, passing several large Polish cities along its way, including Cracow, Sandomierz, Warsaw, Płock, Włocławek, Toruń, Bydgoszcz, Świecie, Grudziądz, Tczew and Gdańsk. With a delta and several branches (Leniwka, Przekop, Śmiała Wisła, Martwa Wisła, Nogat and Szkarpawa) it empties into the Vistula Lagoon, or directly into the Gdańsk Bay of the Baltic Sea.The Vistula is navigable, but large parts of its course do not meet the requirements of modern inland navigation. From the Baltic Sea to Bydgoszcz (where the Bydgoszcz Canal connects to the river), Vistula can accommodate modest river vessels of CEMT class II. Further upstream the river does not have enough depth to allow river barges to navigate. Upstream of Warsaw, a project was undertaken to enlarge the capacity of the river by building a number of locks in Cracow area; this project was never prolonged further downstream, so that the navigability of the Vistula remains problematic. The potential of the river in the decades to come would increase considerably if a restoration of the East-West connection via the Narew – Bug – Mukhovets – Pripyat – Dnieper waterways would be considered. The shifting economic importance parts of Europe may make this option interesting.Vistula runs as a mountain river from relatively clean region of Beskidy Mountains, and its waters are relatively clean until Goczalkowice Reservoir, in this area no industry is located. The river runs thought the heavy industrialized Silesian district, where the main problems are point pollution sources like: coals mines, metal ores mines, metal works, coking plants, and chemical plants. Pollutions are discharged to the river also by its tributaries collecting wastewater from over the region. The Silesian district is also densely populated. Leasing Silesian district, waters are polluted by saline mine waters, sulphates and heavy metals. Downstream impurities cause a problem of water shortage in upstream cites like Cracow  and Warsaw. Further downstream the pollution situation changes a little, however industrial pollution sources still occur, the main problems are pollution from diffused agriculture sources as well highly populated big cites. Sewage from cites are discharged almost directly to the river or they are provisionally purified in WWTP, but the technology used is poor resulting in still high emission of nutrients (nitrogen and phosphorus). The number of WWTP in the Vistula basin is not sufficient; about 70% of sewage is untreated. Vistula poses natural ability to self purification along the course; also an important effect is dilution influence of tributaries like Narew and Bug. Despite water quality increase in downstream areas, the total amount of nutrients discharged to the Baltic Sea increases.ODER:Oder River is placed in the middle Europe,  flowing  through Czech Republic,  western Poland and Germany, ending its flow in the Baltic Sea. It one of the most significant rivers in the catchment basin of the Baltic Sea, second only to the Vistula in discharge and length and the 13th in Europe.Oder River is 854 km long, starting its flow in Oderskie Mountains in Czech Republic, at the altitude of 634 m. The source streams of Oder meet in the rift valley of the Moravian Gate and in the depression of the Racibórz The Oder basin is very developed and exceptionally asymmetrical. Source area of its  left bank tributaries lie in the Sudety Mountains and Sudety Foreland. The main right tributary, Warta, with its length and catchment area is almost equal to Oder.Main cities along the Oder River include: Ostrawa (Czech Republic), Opole, Wrocław, Frankfurt, Szczecin. Catchment area of Oder is rather big and accounts for 118 861 km2, including 106 821 in Poland. The Oder River is an  economically important transport route,  navigable for more than 700 km. It supplements the heavily overburdened railway and highway systems that link the highly industrialized regions of the south with the largest Polish seaport, Szczecin, at the Oder’s Baltic mouth. The river carries about 10% of the total tonnage handled by the port.Barges on the river carry iron, coal, and coke. The Oder is linked by canals with the Spree and Elbe rivers; the Warta connects it with the Vistula River.Oder is navigable over a large part of its total length, as far upstream as to the town of Koźle, where the river connects to the Gliwicki Canal. The upstream part of the river is canalized and permits larger barges to navigate between the industrial sites around the Wrocław area.It is also used in agriculture, especially to improve hydrologic situation of adjacent grounds.Furthermore, water carried by the river is used for many technological processes.The Estuary of the River Oder is one of two biggest river estuaries in the South Baltic Sea and Poland. Its geomorphology and environment conditions make it unique. Its area covers the valley of Oder River-called Międzyodrze and Szczecin Lagoon with catchment of its tributaries: rivers of Tywa, Ina, Gowienica and straits of Dziwna, Świna and Piana. In 1994, Oder Estuary was awarded with a title of “The Landscape of the Year 1993/94” by the International Friends of Nature, an international organisation established in 1895. Although Oder river is assumed to be rather poor in water content, it overflows regularly. The most dangerous and enormous flood which was then called ‘’ the flood of  a century’’- took place in July 1997 and the victims where three big cities : Racibórz, Opole and Wroclaw. The previous big flood in 1905, a bit less serious in consequences, touched Wroclaw by flooding its streets near railway station. It is estimated that annual average pollution loads carried by the Odra/Oder at the mouth of the lagoon are some 56 000 tons of BOD, , 24 000 tons of tot-N, 7 000 tons of tot-P, 920 tons of heavy metals and 2 630 000 tons of chlorides and sulfates . Municipal wastes in the Oder basin are generated in quantities corresponding to 1.0 kg/inhabitant/day. Dump sites, which are by far the most usual method of disposal, are frequently filled close to capacity. Sludge disposal is also problematic in many regions.DANUBE:/Length 2845 km (counting from the primary source Breg 2888 km)/Watershed 795 686 km2  /Discharge for before delta /               -average 6,700 m³/s (229,545 cu ft/s)..Danube is the second longest river in Europe and it flows through 10 European countries: Germany, Austria, Slovakia, Hungary, Croatia, Serbia, Bulgaria, Romania, Moldova and Ukraine (Croatia, Bulgaria, Moldova and Ukraine have access to only one bank). It flows into Black Sea through extended delta. The delta, which is a former bay filled with river sediments, is divided into 3 main branches: Kilia, Sulina and Sfântu Gheorghe. The Danube Delta  is the second largest delta in Europe, after the Volg Delta, and the best preserved on the continent. The greater part of the Danube Delta lies in Romania (Tulcea county), while its northern part, on the left bank of the Chilia arm, is situated in Ukraine (Odessa Oblast) .RHINE:/length: 1310 km,/ avg. discharge: /Basel: 1060 m³/s,/Strasbourg: 1080 m³/s,/Cologne: 2090 m³/s,Dutch border: 2260 m³/s, / origin: Rheinwaldhorn Glacier, Swiss Alps, near the town of Andermatt,/ mouth: near Rotterdam (NL), into the North Sea …Rhine river is the longest river in Germany and it is supplied by its major tributaries – leftside Main and Necker and later Moselle, of which catchment is the north-east France, most of Luxembourg and a small part of Belgium,The major German cities along the Rhine are: Karlsruhe, Mannheim, Ludwigshafen, Wiesbaden, Mainz, Koblenz, Bonn, Cologne, Düsseldorf, Krefeld, Duisburg.The Rhine river is navigable from the North Sea to Rheinfelden near Basel (about 800 km) and about 80% of its ship-carrying waters pass through Germany. The entire distance cannot support ocean going vessels and they must end their journey in Cologne (located between Koln and Bonn). Passenger transport (organized cruises mostly) has been extremely successful on the Rhine due to the cultural aspects (many castles), the scenery, and nature along  the route (what concerns especially Upper Middle Rhine Valley).DNIEPER:Length 2,290 km /Watershed 516,300 km² /Discharge at Kherson  – average 1,670 m³/s The Dnieper River is a river that flows from Russia, through Belarus and Ukraine, to the Black Sea.  The Dnieper’s source is the turf swamps of the Valdai Hills in central Russia, at an elevation of 220 m. The Dnieper is important for the transport and economy of Ukraine.  Large ship locks in its reservoirs, allowing vessels of up to 270×18 metres to access even the port of Kiev and thus create an important transport corridor. The river is used by passenger vessels too. Inland cruises on the rivers Danube and Dnieper have been a growing market in recent decades. Hydroelectric powerThe river is famous for its dams and hydroelectric stations. The most famous was the Dnieper Hydroelectric Station or (DnieproGES) near Zaporizhia, built in 1927-1932 with an output of 558 MW. It was destroyed during Second World War, and rebuilt in 1948 with an output of 750 MW. 

Environment Impact AssessmentAfter the Brutland report and idea of sustainable development every new hydrological structure needs a Env.Imp.Ass. Engineers, ecologists, economics and socialists, should prepare it. Following points should be included in EIA:/Possible alternative solutions/Influence of the new hydr.str on the nv. Should be investigated/Show end life of the hydr struct. What will happen to it when it will be no longer in use-what kind of waste-end life/Estimate influence on hydrological, thermal and chemical regimes/-Evaluate influence on the existing ecosystems/infl. On social and living conditions of people living around/-list the advantages and disadvantages of the hydr.str…The summery should be written in non-technical language for the public to understand. It should show it was done with attention to environment, social, technical and economical problems.