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Water and groundwater 01: general indications

Origins of groundwater by seepage water and back filling from the side -- seasons and groundwater level -- slow move of groundwater -- oasis -- clay layers -- swinging groundwater and springs -- big swamp valley with clay layer - artesian groundwater under pressure -- river is "trenching" and groundwater level is sinking -- formation of caves -- houses in ground water zones -- water vein -- over-exploitation of groundwater by industrialization -- sinking Bangkok, sinking Shanghai, and 50 more sinking towns in China

Origins of groundwater, scheme 03 without clay layer with beach and sea [8]	Strong rain with field [6]. Rain is filling up groundwater underground	Dead baobab tree [z002]. When groundwater level is sinking much in a short time remaining there for some years the trees will die because their roots cannot reach the groundwater any more.

by Michael Palomino (2013)

Part 1: groundwater in general - part 2: pollution and contamination - part 3: salinization, oversalted wells

How groundwater is originated - water one cannot see

Earth does not consist only of rock and sand, but also of caves and underground waterways. In these giant underground caves groundwater is collecting coming from a river, a lake, some rain or floods seeping down the permeable ground, above all during floods of meadows and fields. These caves filled with water are called "groundwater". The area of the river which is enriched with seepage water is called "groundwater flow". There are many caves above all in sand stone and limestone where the water partly is originating the caves itself.

According to the material and structure of the ground the conditions are different:

	Scheme 1: Origin of ground water on the countryside - without clay layer
	Origin of groundwater, scheme 01 without clay layer on Prince Edward Island (PEI, near Nueva Scotia in eastern Canada) [1] Mountains consist of hard rock, and the valley consists of soft alluvial layers. First the mountains were formed by earthquakes and moves of the Earth's crust within millions of years, and during this time the rivers formed alluvial layers in the valleys (sediments, sand and gravel). In these soft layers a lot of groundwater can be found. Also in the crevices ground water and meltwater is entering. All in all about 1/3 of rain water is stored in the crevices and in the soft alluvial ground, and only about 2/3 are flowing in the rivers directly to the sea [web01]. Details: Point 1: Rain is coming down above all in the mountains, but also in the valleys. Rainwater is seeping away. In cold regions there is snowfall in winter and no seepage water but seepage water comes in early spring during snowmelt. In this case the groundwater level is reaching it's highest point BEFORE the vegetation is growing [web01]. Point 2: Seepage water in the mountains is forming a spring originating many creeks and at the end there are rivers. Point 3: Other seepage water in the mountains is not coming out again but is blocked in deposits and cracks and pores. The cracks in the rock are originated by the differences of temperatures during summer and winter or also from day and night. Point 4: River water and rain water is seeping into the soft alluvial ground moving slowly passing the grains of sand and the pebble stones always downwards. This zone is called "groundwater flow" or "groundwater flow system" [web01]. Water is purifying there and is enriched with minerals [web05]. Seepage water is cleaning itself with sand, gravel and limestone [web11], and the more it can sink, the more stones it is passing, and the more minerals it contains at the end. Determination of  the content of minerals is an indication for the deep position of the groundwater  [web12]. In the pores of the first layers there is some air yet and therefore this layer is an "unsaturated zone". Depending to the permeability and the slope the water is passing less fast or faster, sometimes only some meters per year. At the same time plants are also using water for their growth from this unsaturated zone [web01]. This filtration layer can also consist in more than only one layer: Scheme with layers and groundwater. Seepage water is passing several filtration layers [2] Rain - seepage water - groundwater, a children's drawing from Friedrichsfehn in Germany [3] These seepage water zones have to be known and have to be cared carefully, above all when there is a confined aquifer system with two big clay layers. When there is a deforestation for example and all roots of trees are also pulled out and all fertile soil has been washed away (like in stupid Thailand) the ground becomes hard and no groundwater is generated any more. Also after some dry seasons the soil can become so hard that almost any seepage function will not work any more and one has to scarify the ground by hand or with machines. Point 5: This is a first aquifer saturated with water and with sand and gravel which is full of seepage water now like a sponge. There is no air in the pores left. The water table under a layer of sand and gravel is a permanent water table, and during long dry seasons, when the upper layers are drying the groundwater is not in danger [web01]. Point 6: Deep clay layer, only hardly permeable. Point 7: Second aquifer with ground water and sand and gravel, is refilled by waterways coming only from the rocks. Point 8: Deep water deposits in cracks and pores in the heard rock in the mountains. In the valley this hard rock is the base of the groundwater, the "soil layer" [web08] respectively the "aquitard" [web17] When there is a clay layer, water is only passing this clay layer very slowly and the first layers over the clay layer will be saturated then, and the water table will be more or less impermeable (opaque): there will be a "perched water table". And when during a dry season the first layer over a clay layer is drying, then the groundwater is in a general danger because in rainy times hardly any seepage water will fill up the groundwater any more [web01]. The number of groundwater flow systems per river can be varied, or several rivers can also form one single big groundwater flow system [web01].

	Scheme 2: Stratification of the ground with soil zone (stratum), intermediate zone (seepage layer), capillary fringe (saturated zone), and groundwater
	Scheme 2: Stratification of the ground with soil zone (stratum), intermediate zone (seepage layer), capillary fringe (saturated zone), and groundwater [4] See here the basic scheme of ground structure in a moderate climate: Rainfall (thick blue strokes) makes the ground fertile. Point 1: This is the soil zone where the roots of the plants soak their water for their growth in spring and for their life during summer (evaporation) (see the thin blue strokes and the flashes upwards). Point 2: This is the intermediate zone with seepage water (blue points with blue flashed downwards) where the water is cleaning itself with sand and gravel and is taking first minerals. Point 3: here we have the "capillary fringe", the saturated zone. Point 4: water table, water level Point 5: Groundwater, ground water.

Variations of water table according to seasons (in a moderate or alpine climate with snow in winter)

There are 5 seasons with ground water: snowmelt - growth in spring - summer - autumn - winter

5 seasons and the variations of water table [5] During the year in a subalpine climate during the official four seasons with a winter with snow there are the following connections: Spring: During the first time of spring there is snowmelt and much seepage water is entering the ground. Water table is rising and at the end is at it's highest point. Then growing plants are using seepage water in the soil zone so only few water is reaching groundwater. Thus, water table is beginning lowering in the later spring [web01]. Summer: During summer seepage water in the soil zone is going on reducing by higher temperatures and growth of plants and by evaporation by the plant's respiration. Air is more humid in summer by this, and at the same time the water table is always reduced step by step until autumn [web01]. Autumn: Growth of plants finds an end now and temperatures are falling. When there is much rain at the same time groundwater is filling up again [web01]. Winter: When snow is falling there is no new seepage water any more but the first ground layer is freezing and blocked. Therefore the water table is reduced step by step during winter times [web01]. More variations: The variations of water table can be very different from year to year and from location to location. In general the biggest variations are in the upper zones of the river systems with variations of up to 5 meters or more. In the lower parts of the rivers water table is varying only by 1 meter or less. In general never should be used more than 50% of the groundwater [web01]. When groundwater is mainly refilled from the side, or when there are winters without snow and the ground is not freezing during winter times, then groundwater is filled up during rainy winter already. This also counts for tropical climates where only two seasons are differentiated with dry season (sinking water table) and rainy season (rising water table). Strong rain with a field [6]. Rain is filling up ground water and water table is rising Use of groundwater: in subalpine climate not more than 50% On a rainy island like Prince Edward Island in eastern Canada all in all only 2% of the groundwater reserves are used, but in dwelling regions with heavy industries up to 50% are used, the maximum for a preservation of a constant water circulation [web01]. Too high water table provoking death of plants and harvests - eventually swamp After heavy rains or when there is too much irrigation ground water table can rise up to the root zone of the plants. When this is lasting for a longer time the consequences for water sensible plants and complete harvests can be heavy [web02]. When the water table is coming to the surface ("open water table") then swamp is forming [web02]. A swamp, for example here in the Cepkeliu reservation in Lithuania [7]. Water table is coming to the surface. Too low water table during summer times When the first earthy layer is drying out in summer, plants loose contact to seepage water and irrigation has to be performed [web02]. There are several irrigation systems. Most effective is drip irrigation with perforated tube systems. When there is no irrigation plants with short roots are drying out first, thus meadows and crops. After droughts for years or after over-exploitation of ground water the water table is sinking much and also the long roots of trees are loosing their contact with ground water and die. Dried out meadow near Catheys Valley in California [z001]. There is no seepage water in the first earth layer, and there was no irrigation. Dead baobab tree [z002]. When water table is sinking much in a short time and is remaining on a low level for years, trees are dying because their roots cannot reach groundwater any more. Water table have to be controlled exactly for warnings to the population in dangerous situations indicating reducing water consumption (no water washing, no swimming pools etc.).

	Scheme 03: Origin of groundwater without clay layer with beach and sea
	Origin of groundwater, scheme 03, without clay layer with beach and sea [8] Point 1: rain Point 2: springs Point 3: water seeping into cracks in hard rocky layers Point 4: rainwater in soft and not saturated alluvial layers Point 5: groundwater zone with saturated zone ("aquifer") Point 6: groundwater flowing horizontally downwards to the neighboring valley Point 7: groundwater flowing horizontally to the sea draining into the sea Point 8: saltwater penetrating groundwater zone in the aquifer Point 9: plants soaking seepage water in spring and summer.

Scheme 4: speed of groundwater is very very low

Scheme 4: speed of groundwater is very very low [9] Mostly rain water is collected in the mountains where most rain is falling, indicated in the scheme as "recharge area". Rain water is dripping into the soil (in the scheme in violet) and 1/3 of it remains in the ground and only 2/3 are coming out in form of springs. When dripping rainwater is reaching groundwater system with saturated zones, then is is flowing slowly to the side in an inclined line to the river valley. For long distances groundwater can use 10 years (decades), or 100s of years (centuries) or 1,000s of years (millenia). Therefore groundwater in the valley is not only fed from above, but is also "filled up" from the side, but only in a very slow way.

	Scheme 5: desert with oasis with groundwater
	Scheme 5: desert with oasis with groundwater [10] When there are locations without rain - or when there is a desert - and when groundwater is taken out and water table sinks, this groundwater is filling up by waterways in the rock from the side, but only in a very slow way. This groundwater is absolutely precious and needs an effective and spare use. Scene 1: draw well: In a valley palms are living with roots to the groundwater. A village with a draw well was installed there reaching groundwater. Irrigation is made by hand. Groundwater is always in danger for being polluted when something is falling in the well. This groundwater is refilled only from the side in a very slow way and thus is very precious and should be used only sparingly.   Draw wells in the desert [11+12] Scene 2: river in the desert: A river is passing the desert and on it's river sides palm trees are growing with their roots reaching groundwater. In the slope a village was installed and field in the river plain are irrigated with river water. This groundwater is fed by the river and from the side and can be used in moderate quantities, but not too much because water table can sink and also the sedimentary alluvial ground can sink. In the case of a dry season with a dry river a draw well has to be installed. Scene 3: artesian well: Next to the mountains which get regular rainfalls is a desert valley (this situation can be found for example in Chile). The little waterways in the groundwater reach the valley and when a well is installed there water pressure is so high that water is coming out automatically. This groundwater comes from the mountains but it's flowing speed in the layer is very very low. Therefore also this groundwater should be used only sparsely otherwise the water table will sink and also the ground can sink with it.

	Scheme 6: stratification with a clay layer and groundwater below this clay layer
	Scheme 6: stratification with a clay layer and flow system below this clay layer [13] When there is a clay layer then the stratification is changing completely: Point 1: there is an earth layer first with earth, sand, and gravel Point 2: now already follows a saturated layer, a "perched water layer" because the clay layer is the block below Point 3: clay layer, here called a "compacted layer" Point 4: below the clay layer, there is another layer with sand and gravel Point 5: water table Point 6: groundwater. Rainwater is seeping passing the first permeable layer with earth, sand, and gravel (1) and then is forming a saturated layer (2) OVER the clay layer (3). A little part of seepage water is continuing it's way passing the clay layer reaching the next permeable layer with sand and gravel below (4) which is seeped relatively fast. Then the water table (5) and the groundwater is reached (6) [web01, web02]. Groundwater under a clay layer (as in the case of sinking town of Bangkok) is mainly filled from the side in a very very slow way. Therefore this groundwater is very sensitive, precious and should be used only absolutely sparsely. Industries and mega cities using much ground water should NOT be in such locations because water level is sinking and the whole town will sink. In China 50 towns are sinking like this. This situation is also described with two water tables: -- first water table is the perched water table over the clay layer -- and the second water table is the real water table (groundwater table) under the clay layer [web01, web02]. When summer times are very dry drying the first layers groundwater is in heavy danger [web01[. This stratification with a more or less impermeable clay layer The clay layer can be in different deeps. When the clay layer is placed in a short distance to the earth's surface heavy rains or too much irrigation can provoke a swamp [web02]. Such a clay layer can be very varied concerning the dimensions and can be limited locally to under 100 meters [web02]. In other cases like in the case of the sinking town of Bangkok or of sinking Chinese cities the clay layer can reach a dimension of several km2.

	Scheme 7: Saturated layer with clay layer and spring formation and a ground water well 1
	Scheme 7: Saturated layer on a clay layer and spring formation and ground water well [14] Rain water is seeping into the meadow (thick blue strokes). Seepage water is blocked on the almost impermeable clay layer (1) and therefore the seepage water is forming a little floating groundwater (a "groundwater lens" [web04], a "floating aquifer" [web07[) (2). At the same time the clay layer is reaching to the slope where a little part of the water is coming out in form of a spring forming a little creek (3). Another little part of the seepage water is also penetrating the clay layer (see the thin blue strokes) and is reaching the deep main water table (4) and is mixing into the deep ground water zone (5). Rainwater seeping aside of the clay layer is directly reaching the main water table (4) mixing into the deep ground water zone (5). These little clay layers (1) with their saturated zones (2) are very important for forming springs. These little groundwaters are not very deep in the earth and therefore they are heavily in danger being polluted and contaminated by fertilizers or pesticides or other toxic products [web03]. Therefore there should NEVER be any fertilizer or pesticide or industry (mining) in territories with springs (headwaters). In the scheme there are also two wells -- one well drilling (6) was successful respectively it is a "successful borehole" and has met the first little floating groundwater -- the second well drilling (7) was stuck in the soil an the well remains dry. The water of the successful well (6) should only be used sparingly because this ground water is not a big one. Scheme 8: A "floating clay layer" (floating groundwater non-conductor") with a "floating groundwater" on it ("floating groundwater conductor", floating aquifer) and with a big and deep groundwater below (main aquifer) [15] Here in this scheme the floating clay layer (floating groundwater non-conductor) is forming a spring (right) and is forming a conic inclined form at the other end (left) so the groundwater is not only coming out in the spring but is seeping down also at the right side downwards to the main groundwater (main aquifer). Scheme 9: floating groundwater and groundwater near the surface (layer water) [16]
	Scheme 10: saturated layer on a clay layer forming a spring and groundwater wells 2
	Scheme 10: Saturated layer with clay layer and forming a spring, and groundwater wells 2, in a mountain area [17] Also in this scheme we see - now in a little bit more realistic way - the principle of a little clay layer (1), a groundwater lens (2), and forming a spring (3). Rainwater is seeping until to the clay layer forming a little water saturated zone ("groundwater lens"). The seepage water right and left of the clay layer is seeping directly to the big water table (4) and is mixing with the big groundwater system (5). A little part of the groundwater lens is penetrating the clay layer and is also reaching the big groundwater system below.
	Criminalities in the high mountains with mining - for example "Conga" project in the region of Cajamarca in Peru Criminal Peruvian government for example is just doing the contrary to any groundwater protection guideline installing big gold mining industry with any kind of toxics in headwater region of Cajamarca with the "Conga" project - with all possible most toxics like mercury and cyanides. More criminality is not possible.

	Scheme 11: Big swamp valley with clay layer, groundwater and a town on it
	Scheme 11: Big swamp valley with clay layer, groundwater and a town, Santa Clara Valley in California, "U.S.A." [18] Such valleys with a thick clay layer in a little deep under the surface were swamp valleys. They were drained with channels and the soil is never very stable and is not appropriate for high houses. Also ground water can hardly be used because the clay layer is isolating the big groundwater in the depth from rain seepage water and the groundwater is mostly filled up from the sides: Point 1: filling up with ground water coming from waterways in the hard rock ("bedrock recharge", and the speed of this groundwater is very very slow, and Point 2: filling up by rain but only there where the clay layer is NOT existing on the border of the valley in the direct recharge zone ("surface recharge zone"). When there is a big clay layer (3) rainwater is hardly passing it and this is the "confined zone" respectively the groundwater under the clay layer is a "confined aquifer" (4). This means that the deep groundwater (5) in a big dried swamp valley is isolated by a big clay layer and this groundwater is highly sensitive and is filled up from the sides (1 and 2) only in a very very slow way. Drinking water supply of towns and locations in such valleys have to be with reservoirs (6). But in this scheme about Santa Clara Valley in California the reservoir is not for drinking water supply, but is for a percolation pond (7) accelerating filling up of groundwater. In general only little groundwater should be taken out by wells (8) from this sensitive groundwater because there is only a filling up from the sides in a very slow tempo.
	Scheme 12: Big valley with groundwater within two clay layers with an artesian groundwater
	Scheme 12: Big valley with groundwater within two clay layers with an artesian groundwater [19] This constellation is also called "artesian aquifer" respectively "artesian basin" [web18]. When the clay layers are completely shut and close to the mountain ranges then groundwater is under pressure thus wells in the valley are under pressure respectively "artesian wells" can be installed running automatically [web15].

Further details about connections with ground water

Scheme 13: Sinking river is "trenching" into the mountain range provoking a sinking groundwater level

Scheme 13: Sinking river is "trenching" provoking a sinking groundwater level [20] Groundwater level around a big river is defined by the level of the river. When a river is trenching itself into the rock, then also the groundwater level is sinking (pictures b and c). When there is limestone as for example in Jura Mountains or in low mountain ranges in Germany the groundwater is partly dissolving this limestone forming new caves. When water table is sinking the caves will be free and stalagmites and stalactites are formed by little waterways in the limestone (c) [web16]. Scheme 14: Cave formation by groundwater in limestone [21] This procedure of a sinking groundwater table is also happening when rivers are channeled or "lowered". Groundwater is sinking much in a relatively short time and the roots of the trees loose the contact to the groundwater and trees are dying in series. This happened after the construction of the channel of Rhine River between Basel and Freiburg where all birches were killed on the French side of the Rhine.

	Scheme 15a+15b: house built in former groundwater zone
	Schemes 15a+15b: house built in former groundwater zone [22] Building a house with an underground basement is not simple, but groundwaters have to be investigated first, and there has to be found out where eventual clay layers are in the ground so the house will be dry. The house on the picture is breaking through a clay layer (first picture) and now see what happens. There are territories with a big variety of water tables and there will be problems without end with drainage [web06]. In such zones with a big variation of water tables houses should not be built but this soil should be only  worked by agriculture and houses on stilts. When a house is built on the river side then there is a continuous danger that groundwater is "knocking" at the basement. When the river was channeled and was "lowered" thus also the water table was "lowered". Now with climate change the clouds are always more humid provoking more rains and the rivers are provoking floods wanting back their big river beds and ground water is filled up thus water tables are coming up "knocking" at many basements of houses provoking mold and humidity or even floods in the basements which only can be fought with water pumps (second picture). This rise of water tables is happening for example on German rivers Rhine, Main and Moselle. The measures for the houses are waterproofing of basements with bitumen ("black basin") or the construction with waterproof concrete ("white basin") [web09]. The measures for the rivers are the creation of flooding zones giving a part of the river water to the groundwater, and the renaturation and enlargement of river beds reducing flowing paces in a natural way as it had been before the violation of the rivers by pressing them into channels. Renaturations should not permit big quantities of still waters and ponds near dwelling areas otherwise mosquito plagues will be horrible.
	Scheme 16: House in a clay layer with an aquifer on it
	Scheme 16: house in a clay layer with aquifer on it [23] The house in the clay layer is harassed by heavy rains and the clay layer provokes an aquifer respectively a swamp [23]. Sometimes climate change provokes that a house is suddenly in a swamp, for example with defreezing permafrost soil in polar zones in Russia, China, Canada, and Alaska. Houses are slowly sinking into the ground or are inclining and are uninhabitable.

Groundwater channel under the house - "water vein"

Groundwater is also called "water vein" when it is flowing in narrow channels. This groundwater stays under big pressure and is passing sand and gravels so this water in such groundwater channels is under tension and there is a radiation. This radiation can be uncomfortable for humans when the house is placed on such a "water vein". Measures are isolation of the house neutralizing the radiation and protecting the house [web12]. Drawing with water veins in the mountains [z003] Drawing with water veins in the plain passing a house, a street, and there is also a water vein crossing [z004] Sleeping or relaxation in the bed over a water vein should be omitted. Before building a house a dowser should investigate if there are water veins on the territory thus the sleeping room is not built on a water vein. Possible illnesses by water veins and their radiation can be: aches of joints, gout, rheuma, sciatica, migraine, sleeping troubles, depression, tension and sleepiness [web12]. Earth radiation of a water vein cannot be measured with technical devices. A dowser can find and measure them. <A dowser has got the capacity to perceive the magnetic and electric energies provoked by such fault zones and can show this energy with a rod. This capacity principally can learn every person but by our education system most humans have lost big parts of their natural talents. Dowsers are specially formed and can also state what kind of fault zones are present leading to a complex analysis which is absolutely necessary for every local place.> [web12] (orig. German: <Der Rutengänger, auch Radiästhet genannt, hat die Fähigkeit magnetische und elektrische Energien, die durch die Störzonen entstehen, wahrzunehmen und mittels einer Rute in Bewegung umzusetzen. Diese Fähigkeit ist eigentlich jedem Menschen gegeben, jedoch durch unsere Erziehung bei den meisten Menschen nicht mehr stark ausgeprägt. Der Rutengänger ist speziell ausgebildet und kann dadurch auch feststellen, um welche Störzonen es sich handelt, was zur komplexen Analyse der jeweiligen Situation unbedingt erforderlich ist.> Houses can be modified and isolated [web12].

Overexploitation of groundwater and the heavy consequences

Scheme 17: Overexploitation of groundwater by industrialization and destruction of living space (biotopes)

Scheme 17 showing overexploitation of groundwater by industrialization [24] When the ground is of limestone, then water tables can sink but the ground is not sinking, but is "only" leaving caves. In the scheme Nº 17 we see a landscape before industrialization with a high natural water table -- with a wet meadow -- with a river with a natural river bed -- with a wet meadow being fed by the water table -- and with a basic layer (clay or other impermeable rock). Groundwater is the guarantee that creeks and rivers are not dry during dry summer times. Groundwater is "providing the maintenance of wetlands and waterways during times without rain working like a balance in the hydrological balance. [...] Ground water conductor (aquifer) is an excellent water deposit balancing humid and dry seasons because drain is delayed much." [web14] (orig. German: Grundwasser "trägt zur Erhaltung von Feuchtgebieten und Flussläufen bei und gleicht in niederschlagsarmen Zeiten den Wasserhaushalt im Boden aus. [...] Der Grundwasserleiter stellt im Wechsel feuchter und trockener Jahreszeiten und Jahre einen vorzüglichen Wasserspeicher dar, da der Abfluss sehr verzögert ist." [web14] Now destructive industrialization is working badly -- sealing the ground so groundwater gets always less seepage water -- wet meadows are drained or was drying automatically when water tables were falling -- wells are pulling out huge quantities of groundwater provoking enormous falling of water tables locally -- rivers were channeled and "lowered" provoking more falling water tables -- all in all water tables are much deeper and many trees are killed because their roots are loosing contact to the groundwater, river flood plains with all their fauna and breeding places and hatcheries are destroyed. In general a sinking water table has disastrous effects during dry seasons (there is an example of the region of Vogelsberg (bird's hill) in Hesse, Germany: -- water tables were falling by over 40 meters by intensive use of groundwater wells (for example in the region of Kohden in Hesse, Germany) -- during dry summers there is no water reserve any more and groundwater is dry and springs, creeks, ponds, marshes and wetlands are loosing their connection to the groundwater and complete biotopes are dried out, aquatic animals and aquatic birds are eliminated -- there are sinking territories provoking waterlogging after submergence of ground, there are sinking craters, sinking territories in agricultural zones -- houses get cracks by damages in sinking territories.

Scheme 18: Overexploitation of groundwater: sinking town of Bangkok on a clay layer - and more sinking towns

Big valley with clay layers, with a heavy megacity and with overexploitation of groundwater, e.g. sinking town of Bangkok [10] Scheme 18: Sinking Bangkok on a swamp ground with a clay layer and with overexploitation of groundwater [25] The town of Bangkok is on a soft drained swamp ground. Heavy buildings are on stilts on a hard clay layer, but at the same time there is a heavy overexploitation of groundwater, so the town is sinking 5 to 10 cm per year - and the groundwater is filled up only from the side - that means, in a very very slow way. Before the valley was swamp formed by the clay layer blocking the rainfall forming swamp land with lakes and lake districts. Humans have drained the swamps and were constructing towns, first with wooden houses which was no problem for the soft soil. But with heavy stone houses and with skyscrapers the problems came up. In Mexico City for example many heavy houses are sinking into the mud ground of a former lake. What is happening in Bangkok? Example of sinking Bangkok (scheme 18) In Bangkok in Thailand heavy stone houses and skyscrapers have 15 meters long stilts being fixed on the hard clay layer. But at the same time the government of Bangkok is supplying a part of the drinking water supply on the base of the groundwater, and additionally the government authorized industries using much groundwater. It seems as if the government means that there is no harm with it. But the result is a sinking town of Bangkok sinking 5 to 8 cm each year, a world wide record: -- water table is sinking because the groundwater is only refilled from the sides with a very slow pace -- add to this the recharge zones for the confined groundwater under Bangkok have been deforestated and soil has become hard and hardly any new groundwater is generated -- the clay layer is sinking with the water table -- the whole town of Bangkok is sinking, some districts more, some districts less, above all there where industries are pulling groundwater out -- some districts of Bangkok are already under sea level and people and industries should be evacuated there -- and there is a heavy danger of salting the groundwater because Bangkok is not far from the coast line. Example of sinking Shanghai In Shanghai the town is sinking already since 1900 because the houses are always heavier and because too much groundwater is used: -- water tables are sinking -- and the whole town of Shanghai is sinking -- Shanghai is fighting against salting of ground water pumping drinking water into the ground in coastal zones -- water supply with river waters and lakes or reservoirs is not existing. Measures for sinking towns We see when Bangkok does not want to drown then this town has to install at once a water supply coming from outside with reservoirs and clarified river waters so no groundwater is consumed any more. Rivers have to be kept cleaned so river waters can be used for drinking water in the lower parts of the river. Additionally it seems that big parts of such towns have to be shifted to safe grounds discharging the clay layer and the swampy soil in general. When there are permeable zones there have to be agricultural zones filling up the groundwater also from above. The same counts for Shanghai and also for sinking Mexico City and for about 50 more sinking towns in China.

Part 1: groundwater in general - part 2: pollution and contamination - part 3: salinization, oversalted wells

Sources
[web01] Prince Edward Island: Groundwater: http://www.gov.pe.ca/environment/index.php3?number=1015822&lang=E
[web02] Soil and water: http://www.fao.org/docrep/R4082E/r4082e03.htm
[web03] Perched ground water: http://www.dwa.gov.za/Groundwater/Groundwater_Dictionary/index.html?introduction_perched_groundwater.htm
[web04] floating aquifer (hängender Grundwasserleiter): http://hydrologie.org/glu/IT/GF0891IT.HTM
[web05] groundwater (Grundwasser): http://www.grundschule-friedrichsfehn.de/projekte/wassertropfen/wasserreinigung/grundwasser.html
[web06] Seasonal high water table in Lake County: www.lakecountyohio.gov/swcd/Landowners/HighWaterTables.aspx
[web07] floating groundwater (schwebendes Grundwasser): http://www.geodz.com/deu/d/schwebendes_Grundwasser
[web08] Fachdokumente zu Altlasten: http://www.fachdokumente.lubw.baden-wuerttemberg.de/servlet/is/10105/mtbe0012.html?COMMAND=DisplayBericht&FIS=161&OBJECT=10105&MODE=BER&RIGHTMENU=null
[web09] http://www.wuerzburg.de/de/themen/umwelt-verkehr/wasserrechtgewaesserschutzwasserwirtschaft/grundwasser/15316.Bauen_und_Grundwasser.html
[web10] Protection Community Vogelsberg e.V.: overexploitation of water (Schutzgemeinschaft Vogelsberg e.V.: Wasserraubbau):
www.sgv-ev.de/page/index.php?page=wasser&cur=raub

[web11] groundwater (Grundwasser): http://www.primolo.de/archiv/grugro/hp_innen6.htm
[web12] information about water veins (Informationen zu Wasseradern): http://www.rutengaengeraktuell.de/infos/wasseradern/wasseradern.html
[web13] http://www.land-oberoesterreich.gv.at/cps/rde/xchg/ooe/hs.xsl/18696_DEU_HTML.htm
[web14] groundwater (Grundwasser): www.lanuv.nrw.de/wasser/grundwasser.htm
[web15] groundwater in a big valley in clay layers, artesian groundwater (Grundwasser im grossen Tal in Tonschichten mit artesisch gespanntem Grundwasser):
http://www.wwa-an.bayern.de/wasser_erleben/lehrpfade/burghaslach/stationen/index.htm
[web16] Groundwater: http://earthsci.org/education/teacher/basicgeol/groundwa/groundwa.html
[web17] Groundwater: http://earthsci.org/education/teacher/basicgeol/groundwa/groundwa.html
[web18] artesian aquifer, artesian basin: http://en.wikipedia.org/wiki/Artesian_aquifer

Photo sources
[1] Scheme 1: origin of groundwater: http://www.gov.pe.ca/environment/index.php3?number=1015822&lang=E
[2] stratification and groundwater: http://www.land-oberoesterreich.gv.at/cps/rde/xchg/ooe/hs.xsl/18696_DEU_HTML.htm
[3] rain - seepage water - groundwater, children's drawing from Friedrichsfehn, Germany:
http://www.grundschule-friedrichsfehn.de/projekte/wassertropfen/wasserreinigung/grundwasser.html
[4] Scheme 2: stratification of the soil with soil layer, seepage layer, capillary layer, water table and groundwater: th.wikipedia.org/wiki/น้ำบาดาล
[5] 5 seasons: snowmelt - growing spring - summer - autumn - winter:
-- 4 seasons in Bad Waldsee, Germany: http://www.fotocommunity.de/pc/pc/display/26765106
-- snowmelt on a golf course in Saint Michael in Lungau, Austria: http://www.meinbezirk.at/sankt-michael-im-lungau/magazin/schneeschmelze-im-lungau-d143829.html
[6] strong rain with a field: http://putzlowitsch.de/2012/06/30/autofahrt-mit-hindernissen-aste-auf-der-strase/
[7] swamp in the Cepkeliu reservation in Lithuania: http://de.wikipedia.org/wiki/Sumpf
[8a] Scheme 3: origin of groundwater, scheme 2: http://www.ec.gc.ca/eau-water/default.asp?lang=En&n=300688DC-1
[8b] clouds: http://de.123rf.com/photo_10422366_set-der-comic-stil-sprechblasen.html
[9] scheme 4: streaming paces of groundwater: http://pubs.usgs.gov/gip/gw_ruralhomeowner/
[10] scheme 5: deserts and oasis with groundwater:
http://www.klett-pressebox.de/sixcms/list.php?page=miniinfothek&node=Oasen&miniinfothek=Religion%20Infothek&article=Infoblatt+Oasen

[11] draw well in the desert: http://www.pixelio.de/search/ziehbrunnen
[12] draw well in the desert in Tunisia: http://www.1000urlaubsideen.de/individualreisen/kamel-trekking-steppen-loudais-bis-zu-hohen-dunen-awinsabat
[13] scheme 6: groundwater flow with clay layer and groundwater: http://www.fao.org/docrep/R4082E/r4082e03.htm
[14] scheme 7: groundwater flow with little clay layer and a spring over it:
http://www.dwa.gov.za/Groundwater/Groundwater_Dictionary/index.html?introduction_perched_groundwater.htm
[15] scheme of a floating aquifer, floating groundwater: http://www.geodz.com/deu/d/schwebendes_Grundwasser
[16] floating groundwater and groundwater near the surface (layer groundwater):
http://www.stadtentwicklung.berlin.de/umwelt/wasser/hydrogeo/de/gw_gleichen.shtml
[17] scheme 8: groundwater flow with little clay layer and a spring over it 2: http://hydrologie.org/glu/IT/GF0891IT.HTM
[18] scheme 9: big valley with clay layers, ground water beneath and town over it, Santa Clara Valley, California: http://www.museumca.org/creeks/z-groundwater.html
[19] valley with clay layers and artesian water: http://www.wwa-an.bayern.de/wasser_erleben/lehrpfade/burghaslach/stationen/index.htm
[20] scheme 11: sinking river in a lime stone mountain range with sinking water tables and caves: http://www.museumca.org/creeks/z-groundwater.html

[21] cave formation by groundwater: http://earthsci.org/education/teacher/basicgeol/groundwa/groundwa.html
[22] scheme 12a+12b: house breaking through a clay layer: http://www.lakecountyohio.gov/swcd/Landowners/HighWaterTables.aspx
[23] scheme 13: house breaking through a clay layer with an aquifer on the clay layer: http://www.lakecountyohio.gov/swcd/Landowners/HighWaterTables.aspx
[24] scheme 14: overexploitation of groundwater by industrialization: http://www.sgv-ev.de/page/index.php?page=wasser&cur=raub
[25] scheme 15: sinking Bangkok: http://www.museumca.org/creeks/z-groundwater.html, varied by Michael Palomino

[z001] dry meadow near Catheys Valley in California:
http://de.123rf.com/photo_656809_red-landwirtschaftlichen-gebauden-gegen-trockene-ausgetrocknete-h-gel-morgan-hill-kalifornien-usa.html
[z002] dead baobab tree: http://www.feierabend.de/Suedliches-Afrika/Pflanzenwelt/Baobab-26615.htm
[z003] drawing with water veins in the mountains: http://vitalist.info/das-konnen-wir-fur-sie-tun/erdstrahlen-geopathogene-strahlung/wasseradern/
[z004] drawing with water veins in the plain with house, street and water vein crossing: http://www.rutengaengeraktuell.de/infos/wasseradern/wasseradern.html

           

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