Tuesday, August 12, 2014

Beware of the hills.


Frequency of landslides in India is indeed increasing. 



By
Dr. Nitish Priyadarshi
Geologist.

Malin, the village in Pune district that was flattened by a landslide few days back claiming more than 130 lives, has brought the focus back on the management –or mismanagement – of the vulnerable hills of India especially Western Ghats, Himalayas and North Eastern states.

The torrential rain on July 30 near Pune perhaps would not have brought down a side of the hill had it not been weakened by quarrying, leveling and deforestation activities banned in the old weathered hills and ecologically sensitive areas.

Last year it was Uttrakhand this year it is Malin and Nepal. A massive landslide in Nepal  triggered by continuous monsoon rains, caused 10 deaths, displaced 5,000 families and destroyed dozens of houses. The landslide has also blocked the Sunkoshi River and forming a lake which is threatening to cause downstream flash floods.

Heavy rainfall in June last year wreaked havoc across Uttarakhand, causing rivers and glacial lakes to overflow and triggering massive landslides – killing almost 6,000 people. Construction of hydroelectric dams, deforestation and the spread of unregulated buildings along riverbanks magnify the impact of the monsoons.

Development works carried out in pursuit of greater economic growth – such as the construction of dams and deforestation – are putting people and the environment at greater risk when disasters strike.
India is one of the most disaster-prone countries in the world, and many of its 1.2 billion people live in areas vulnerable to natural hazards such as floods, landslides, cyclones, droughts and earthquakes.


Landslides are a natural hazard that affect at least 15 percent of the land area of our country, covering an area of more than 0.49 million sq. km. landslides of different types occur frequently in the geo-dynamically active domains in the Himalayan and North-Eastern parts of the country as well as relatively stable domain in the Western Ghats and Nilgiri hills in the southern part of the country. Besides, sporadic occurrences of landslides have been reported in the Eastern Ghats, Ranchi plateau, and Vindhyan plateau, as well. In all 22 states and parts of the Union Territory of Pudducherry and Andaman and Nicobar Islands of our country are affected by this hazard, mostly during monsoons.

Landslides Zonation Mopping is a modern method to identify landslides prone areas and has been in use in India since 1980s.The major parameters that call for evaluation are as follows:
  1. Slope-Magnitude, length and Direction
  2. Soil thickness
  3. Relative relief
  4. Land use
  5. Drainage- pattern and density
  6. Landslide affected population
Causes of Landslides

Landslides can be caused by
1. Poor ground conditions
2. Geomorphic phenomena.
3. Natural physical forces
4. Quite often due to heavy spells of rainfall coupled with impeded drainage.
A Checklist of Causes of Landslides Ground Causes
  1. Weak, sensitivity, or weathered materials
  2. Adverse ground structure (joints, fissures etc.)
  3. Physical property variation (permeability, plasticity etc)

The Himalayan mountain ranges and hilly tracts of the North-Eastern region are highly susceptible to slope instability due to the immature and rugged topography, fragile rock conditions, high seismicity resulting from proximity to the plate margins and high rainfall. Extensive anthropogenic interference, as part of developmental activities, is another significant factor that increases this hazard manifold. As a result, the landscape in the Himalayan and North-Eastern regions is highly susceptible to reoccurrence of landslides.

Similarly, the Western Ghats overlooking the Konkan coast, though located in a relatively stable domain, experience the fury of this natural hazard due to steep hill slopes, overburden and high intensity rainfall. The Nilgiri hills located at the convergence zone of the Eastern Ghats and the Western Ghats bear the innumerable scars of landslides due to their location in a zone of high intensity and protracted rainfall where overburden is sensitive to over-saturation.

Vast areas of western Sikkim, Kumaon, Garhwal, Himachal Pradesh, Kashmir, and several other hilly regions have been denuded of protective vegetal cover, which has been reduced to less than 30 percent, which is less than half of what would be considered desirable. As the pressure of population grew rapidly, more and more human settlements, roads, dams, tunnels, water reservoirs, towers and other public utilities came up in vulnerable areas. The road network in the Himalayan region is more than 50,000 km in length. A large number of dams have been built in the Himalayan region. Quarrying and mining, for example, in the Doon valley, Jhiroli (Almora) and Chandhak (Pitthoragarh) have inflicted heavy damages to the slopes and the associated environment.

According to the information obtained under RTI, In Mumbai city over 22,483 hutment in 327 hilly areas across 25 Assembly constituencies in the city, including Western and Eastern suburbs, are dangerous and the people living there need to be shifted as soon as possible. In the main city, 49 spots are dangerous in which total hutments are 3986, while in Mumbai Suburb 278 spots are most dangerous.

An overall evaluation of the pattern and nature of landslide occurrences in the Kerala part of Western Ghats and its corresponding eastern flank falling within Tamil Nadu reveals the following main features:

1.      Almost all mass movements occur during monsoons (SW and NE monsoon) in the western flank of Western Ghats and during occasional cyclonic events in the eastern flank indicating that main triggering mechanism is the over- saturation of overburden caused by heavy rains.
2.      There seems to be a relation between intensity of rainfall and slope failures.
3.      Majority of the catastrophic mass movements is confined to the overburden without affecting the underlying bedrock.
4.      Improper land use practices such as heavy tilling, agricultural practices and settlement patterns have contributed to creep and withdrawal of toe support in many cases.
5.      A common factor noticed in most of these vulnerable slopes deforestation in the recent past, cultivation of seasonal crops and increase in settlements.
6.      In some areas developmental activities like construction of buildings, road cutting, embankments, cut and fill structures causes modification of natural slopes, blocking of surface drainage, loading of critical slopes and withdrawal to toe support promoting vulnerability of critical slopes.

Frequency of landslides is indeed increasing. The main reasons for this are primarily unplanned development in landslide prone areas which can change the geomorphology of that area. Because of accelerated deforestation, rampant urbanization, high frequency of earthquakes, fragile geological structures, steep topography and intense rainfall in the mountainous regions of the South Asia, the number of fatal landslides, casualties and economic loss is increasing year by year. Increasing extreme events due to climate change are also responsible for this phenomenon. Rainfall is becoming extreme in India, either heavy or scanty. If there is a lot of rainfall in a short span of time, then the soil is not able to absorb the moisture, which makes it vulnerable to erosion and slope instability, eventually leading to landslides.



The Himalayan and North-Eastern regions are potential sites where landslides dams have formed at many places in the past and the potential of such occurrences in the future is high.

Reference:

National disaster management guidelines, June 2009. National disaster management authority, Government of India.

 

Wednesday, July 16, 2014

Importance of Geotourism, with special reference to Jharkhand State of India.



The aim of Geotourism is to make visitors aware of, and to gain some

understanding of, the geological features that surround them.

by

Dr. Nitish Priyadarshi
Geologist. 




Geotourism is the kind of travel that sustains or enhances the geographical character of a place — its environment, culture, aesthetics, heritage, and the well-being of its residents.



Geography—from which “geotourism” derives—is not just about where places are. It’s also about what places are. It’s about what makes one place different from the next. That includes not only flora and fauna, which is the realm of ecotourism, but also historic structures and archaeological sites, scenic landscapes, traditional architecture, and locally grown music, cuisine, crafts, dances, and other arts. Many people sum up that combination of elements as “sense of place.” Since most tourists travel with a variety of interests, geotourism’s holistic approach provides a synergistic effect unavailable to niches like adventure, eco-, or historic tourism. Geotourism speaks to the widest possible market that is compatible with sustaining a destination’s distinctive qualities.


At its simplest geotourism is tourism with some connection to geology or geomorphology.

For many years, environmentalists have strived to make the general public aware of the importance of preserving the quality of an environment. Most individuals are also aware of the many transgressions that are committed against nature in order to further money making industries. These have caused a massive decline in the well-being of the economy and to those who are living in it. This does not only refer to people alone but to the entire ecology including animals, plants, and other natural structures.

Protecting the environment from exploitation whilst encouraging economic and community development is one of the main reasons behind the formulation of the different approaches to tourism. There are currently three basic approaches and this includes ecotourism, sustainable tourism, and geo tourism.

Geo tourism is otherwise referred to as the knowledge based tourism. It seeks to provide tourists with relevant information on the formation of a place’s geology and geomorphology. This means that geo tourism goes beyond just showing off great sights. It takes things a notch higher by informing tourists of how these wonders came to be. An example of this is a discussion of rock formations and its mineral components or how a cave’s inner structure has been created with features such as stalagmites and stalactites. Apart from these, geo tourism is also involved in encouraging both the local community and the tourists to work together in maintaining the quality of each geological site by following the preservation guidelines that are already in place.

One of the major reasons for this is that geo tourism minimizes the negative effects of tourism such as environmental pollution. Places that implement geo tourism has been a huge advantage for many travellers, called geo tourists, since they are provided with an extremely rich experience that involves an immersion in the culture, heritage, and the natural resource of a certain tourist destination. The visitors do not only serve to improve the economy but also help in preserving the environment. It respects local culture and tradition. Foreign visitors learn local etiquette, including at least a few courtesy words in the local language. Residents learn how to deal with foreign expectations that may differ from their own.

Most geo tourists will patronize business establishments such as resorts, hotels, or restaurants that operate under environment friendly conditions. Tourist satisfaction is also enhanced. This means that when they get back to their place of origin, they will be able to tell their families and friends about how positive their travel experience has been. They will also be able to impart the knowledge that they have obtained from the trip to others. Those who hear of these tales will be encouraged to visit the tourist destination themselves.

Geotourism deals with the natural and built environments.

Geotourism was first defined (Hose, 1995) in England. There are two viewpoints of geotourism:
  1. Purely geological and geomorphologically-focused Sustainable Tourism. This is the definition followed in most of the world.
  2. Geographically Sustainable Tourism, the most common definition in the USA. This emphasises preservation of the geographical sense of a place in general, beyond simple geological and geomorphological features.


Case study of Jharkhand state.

Why does Jharkhand need geotourists ?

1. Tourism: an increasingly important contribution to the economy.

2. Creation of jobs for local people: tour companies, drivers, guides, accommodation providers, food outlets.

3. Although Jharkhand has beautiful and interesting wildlife, it cannot compete with the game parks of other parts of the world.

4. However, it has two big advantages over them: unique historical sites and unique and spectacular geology.

5. Therefore promotion of Jharkhand’s geological attractions is important.
6. Ensures that tourists appreciate fully ALL the attractions Jharkhand has to offer!

7. Conservation of important geological sites.


When we speak about Geotourism the attention is usually preferentially paid  to two main aspects involved
 in this concept: on the one side the Geology itself, and the geological values of the area, i.e. the scientific interest of the site, as the main subject of attraction for both geologists, visitors and tourists. on the other side, the Administrations, at local or national level, which should set an adequate legal framework, in close agreement with geologists, to define, promote, arrange, restore and support the maintenance costs of the protected sites.

Nature has sculptured many eye-catching features by geological processes. Jharkhand has been bestowed with a large number of such magnificent geological sites spread throughout its length and breadth and spanning over the entire length of the geological time scale. These sites attract not only the earth scientists but also the common man. These natural exquisite land sculptures have become nature lover's delight and are gaining importance as tourist spots.

The Chotanagpur Plateau serves as a meeting place for the Himalayan and Peninsular biospecies. Here, you find a portion of the oldest part of the earth’s crust, making it the most ancient geological formation in the country.

Jharkhand geological Heritage spans over million years (Archeans to Recent) with substantial part of it exposed at surface. World class exposures of rocks and fossil combined with breath taking scenery and culture make the perfect blend for life time geo-tourism experience. The Chotanagpur plateau region of Jharkhand is made up mainly of Precambrian rocks but has witnessed uplifts synchronously with the Himalayan uplift in the Cenozoic.

Many of the rock and fossil exposure can be utilized for their scientific value and serve as leisure trips at the same time. This sector is possibility orientated towards local, regional and international educational institutions and research centers.  The second sector is a general tourism which contains some element of geology in otherwise mostly scenic and cultural setting and mostly enjoyed by laymen tourists.

The Jharkhand state is well known for spectacular scenery and geology. The record of the Earth's history in Jharkhand is unique. It provides the best exposure in the world to study ancient rock types. Numerous areas in the Jharkhand state offer immediate opportunities for geotourism because of the presence of a diverse range of geological phenomena and outcrops including, amongst many, landforms, structures, residual hills, folding, faulting, water falls, ancient rock paintings, ancient rock carvings, caves, pegmatite intrusions, minerals and fossils. 




Places which can be developed as Geo-tourist spot in Jharkhand.


  1. Ranchi district: Hundru falls, Dasam falls, Jonha falls, Sita falls, Hirni falls, Ranchi hill, Tagore hill, Joda (twin) hills, Bariatu hills, Panchghagh falls, Pithoria valley, Sutiambe hills.
  2. Rajmahal Hills are hills formed from rocks dating from the Jurassic Period and named after the town of Rajmahal which lies to the east in the state of Jharkhand in India. Rajmahal hills are home to plant fossils which are 68 to 145 million years old. Moti Jharna may also be developed as geo-tourist spot.
  3. Hazaribag district: Canary  hills, Parasnath hills, confluence of Bheda and Damodar river in Rajrappa near Ramgarh.
  4. Suraj kund in Hazaribag district: Suraj Kund is a major tourist attraction given its unique distinction of being the 'hottest' hot water spring in India. The spring's waters which have curative properties are always at a temperature of 87 degrees celsius. There are five pools in this place namely Surya Kund, Lakshman Kund, Brahm Kund, Ram kund and Sita Kund which contain hot water of different temperatures. The main Kund is considered to be Surya Kund and it has the hottest water in it.
  5. Dalma range in Singhbhum: The Dalma range marks the belt of Archaevan lava flows. "The structural base of the region is  provided by a series of batholithic intrusions of granite into  Dharwar strata, which were intensely metamorphosed by orogenetic movements.
  6. Abandoned coal mines and other mines of Jharkhand including underground mines.
  7. Roro hills:  About 20 kilometers west of Chaibasa, the headquarters of West Singhbhum district of Jharkhand, lies the Roro hills-- home to an abandoned chrysotile asbestos mine. The Roro mines were closed down in 1983 after Hyderabad Asbestos Cement Products Ltd. (now known as Hyderabad Industries Limited) decided that they were no longer profitable.


This all looks very interesting but what is it?



How such rocks are formed?

 Mystery of Hazaribag Hot springs.
 How such big hills are formed?


 How such structures are formed on rocks?

 Typical rock weathering.


How such hills are formed?




How such caves are formed?


What is this?


How such hills are formed?


How falls are formed?

Formation of valleys.

 
How such structures are formed?



 To understand formation of folding.


How such caves are formed?

Mystery of dome gneiss.

What are there inside such mines?

 To understand formation of such caves.

How pegmatite intrudes in host rock?




                    Roro hills near Chaibasa.




 How such structure of the hills are formed ? ( Its near Jamshedpur).

CONCLUSIONS

Only if we are able to understand Geotourism as a touristic, not academic, activity and make a real effort to make Geology an attractive issue related with the explanation of the beauty of landscape and with disentangling the mysteries of life and earth, far from the complexity of scientific concepts and geological processes we shall be ready to make Geology an interest subject for tourists. If we are conscious that, when talking about Geotourism and its touristic components, besides Geology we are speaking about accommodation and eating facilities, the quality of accesses and services, and the excellence and attraction of merchandising products we shall be able to make Geotourism equally attractive as other classical modalities of tourism. On the contrary, if we identify Geotourism with teaching of Geology or with explaining Geology to groups, we will focus on a separate matter that may be interesting for some visitors but risks to be boring for the general tourists.


Reference:

Hose, T. A. (2012), “ 3G’s for Modern Geotourism ”, Geoheritage Journal, 4: 7-24




















Wednesday, July 2, 2014

Sand mining is going to be new battleground.



Illegal and indiscriminate river sand mining is going to cause a large number of environmental and social problems in World.

By
Dr. Nitish Priyadarshi
Geologist.

 This is Kanchi river which provides sands to Ranchi district.


 This is Jumar River near Ranchi which now contains less sand deposit due to over exploitation.



Illegal sand mining is a scourge in states across India. The latest battle in Gautum Buddh Nagar, Uttar Pradesh, where sub divisional magistrate (SDM) was suspended from service, has served to highlight the plight of rivers ravaged.

Construction work on projects worth thousands of crores of rupees in Jharkhand has been affected by a sand crisis caused by the on-again, off-again auction policy.

River sand is a product of natural weathering of rocks over a period of millions of years. It is mined from the river beds. River sand is becoming a scarce commodity now. River (Fresh water) sand is far superior for construction purposes than any other sand used in construction.

Due to the crisis, prices of river sand have gone up to Rs.7,000 per truck from Rs.3,000 per truck before the current round of auctions started and then halted due to protests. This is because the raw material has to be brought from outside the state.

It is unfortunate that the Jharkhand state is facing a sand crisis and projects worth more than Rs.3,000 crore have been affected. This crisis has been created by the state government. It is the duty of the state government to facilitate licenses and environmental clearances. Construction work has been badly affected in the state.

Illegal sand mining is adding to the plight of the Yamuna river in the National Capital Region. It has not only changed the course of the river but also made its riverbed unstable, thus disturbing the biodiversity of the region.

While farmers from nearby villages claimed that people involved in illegal sand mining intentionally prevent the natural flow of water to take out more sand from a spot, experts claimed that it actually leads to change in the course of river.

The Karnataka government has attempted a rare balancing act between the needs of rivers and buildings for sand. This conflict between the environment and development was addressed by issuing an order to the public works department (PWD) on September 16, 2013 mandating the civil body to use only manufactured sand (M-sand) instead of river sand for all its building activities. A move widely seen as a good initiative aimed to plug the demand-supply deficit in order to ease pressure on sand mining. Shifting of PWD, one of the major consumers of sand in the state, to M-sand is bound to ease prices of sand in the market and also curb illegal sand mining. Point to be noted here is that M-sand is nothing but crushed rock, that too mostly granite. Though it yields higher quality concrete, but the questions one needs to ask are these: Are we really solving the environmental concerns? Isn’t it a misplaced attempt as rocks are also minerals that need to be conserved?

As humans we’re a race that takes everything for granted, and that’s evident in the way we’ve recklessly consumed most of our natural resources. Take a look around, we haven’t spared much in the name of development. Whether it’s coal, water, oil or even natural gas, we’ve managed to diminish it all. But did you know that sand falls into this list as well? That it’s an extremely essential natural resource being used everywhere, right from cement, concrete, glass, computer parts, smart phones, toothpaste, cosmetics, paper, paint, tires and so much more! But sand isn’t an unlimited resource. It’s in fact one of the most consumed and underestimated resources in the world and with 70 per cent of world beaches disappearing, we haven’t the slightest idea what the repercussions will be in the future.

Ranchi city in Jharkhand State receives sand from only Kanchi river now. Earlier sands of two more rivers were used for construction. Now in both rivers the deposits of sands have been affected due to over exploitation especially of Jumar river flowing north of city. 

Sand being so in demand (it’s fuelling the construction boom everywhere), the industry has already consumed most of it available in quarries and rivers. Sand from the deserts cannot be used for construction as the grains are rounded and polished (due to winds) and do not stick together, which is essential for construction. The industry has no option and is turning to the sea and beaches to meet its insatiable demand. Illegal sand mining is already underway in 70 countries around the world.

Sand-rivers providing perennial water supply some sand-rivers provide water throughout all the years due to the favourable features of:

• The floor under the sand in a riverbed forms an upwards dyke which traps water upstream of it. An underground reservoir is thereby created from where water can be drawn. In Jharkhand state of India people residing near the banks of polluted Damodar and Swarnarekha River are more dependent on river sands for drinking water than consuming directly from the river. They dig the sand to trap clean water.

• Coarse sand and gravel in sand-rivers can trap and store 50 per cent of water in the voids between the solids of sand. Up to 35 per cent of this water can be extracted. In other words, 350 litres of water can be extracted from every cubic metre of sand.

Sand is not a sustainable resource and though it regenerates, it is being consumed faster than its  rate of creation. It takes 25,000 years to create sand from the mountains and sand stone, which breaks down and flows down little streams, down rivers to deltas and then gets carried to the ocean by the waves and tides. Much of the sand never makes it to the ocean because of dams which trap the sand. There are about 8,45,000 dams in the world. In the US alone there are around 80,000 dams. In China, it is estimated that by 2020 not one river will reach the sea. Thanks to these dams, much of the sand that could reach the sea won’t do so.

Most of us think of sand as a necessary ingredient for any beach vacation. Yet those seemingly insignificant grains of silica surround our daily lives. Every house, skyscraper and glass building, every bridge, airport and sidewalk in our modern society depends on sand. We use it to manufacture optical fiber, cell phone components and computer chips. We find it in our toothpaste, powdered foods and even our wine (both the glass and the wine, as a fining agent)! Is sand an infinite resource? Can the existing supply satisfy a gigantic demand fueled by construction booms? What are the consequences of intensive beach sand mining for the environment?

By the end of the 21st century, beaches will be a thing of the past. That is the alarming forecast of a growing number of scientists and environmental NGOs. Sand has become a vital commodity for our modern economies. The worldwide construction boom fuelled by emerging economies and increasing urbanization has led to intensive sand extraction on land and in the oceans, with damaging environmental impacts.
The construction industry requires massive amounts of sand for its projects.  Despite some legal framework prohibiting sand mining in most states, the industry gets most of the sand by dredging rivers’ earthen materials beyond a safe capacity.   In almost every river where it is viable, the ‘sand mafia’ purge the depths for profitable sand, amounting to an illegal yearly turnover of Rs. 1000 crore.   Despite its illegality, sand mining is perpetuated by various social and economic dilemmas.  First, it brings revenue to state government and panchayats, which paves the way for corruption and conflict.   Thus, relationships between local politicians, contractors, and bureaucrats emerge to create a power nexus capable of deterring community-based resistance.   The players in this nexus are infamously termed the’ sand mafia,’ by the media. 

The case of Maharashtra epitomizes this phenomenon.   In September 2010, the Bombay High Court banned the extraction of sand, due to its adverse environmental effects and detriment to water supply.  If this ruling had stuck, the real estate industry would have suffered a loss of Rs. 2,000 crore.   The High Court asked the government to come up with a new policy on sand mining after the court appointed Indian Institute of Technology submitted a report. On 20 Oct 2010, State cabinet approved a new sand mining policy that empowers communities to have a say on sand mining in their localities. The policy also bans use of suction pumps in dredging but fails to ban mechanized dredging. Moreover, the High Court directed the Maharashtra government not to award any contract or allow any sand excavation to commence across the state "until and unless" it first obtained environmental clearance as contemplated in its latest policy decision.

The environmental reasons for this ban and others across India are numerous. Sand acts as an aquifer, and as a natural carpet on the bottom of the river.  Stripping this layer leads to downstream erosion, causing changes in channel bed and habitat type, as well as the deepening of rivers and estuaries, and the enlargement of river mouths.    As the river system lowers, local groundwater is affected, which leads to water scarcities aggravating agriculture and local livelihoods.  In terms of legal measures, ground water shortages have been noted as the patent problem with river sand mining.  Less considered in legal action, but centrally relevant, experts also note substantial habitat and ecological problems, which include “direct loss of stream reserve habitat, disturbances of species attached to stream bed deposits, reduced light penetration, reduced primary production, and reduced feeding opportunities”. key issues have not been resolved.

The rivers in Kerala have been subject to significant such degradation, and serve as a good overview of the aforementioned problems.  Major rivers such as the Pampa, Manimala, and Achankovil have been subject to such non-discretionary dredging that there has been a sharp fall in ground water table levels.  According to one study, indiscriminate mining has lowered the Pampa an average of three to four metres, and up to six metres in some areas.

Sand smuggling is continuing unabated in Krishna district despite the ‘preventive measures’ by the official machinery since the sand mafia is enjoying the support of the politicos.

While the government stopped the sand auctions due to legal and administrative issues as well as pressure from the politicos for more than a year, the sand mafia is minting money by transporting the sand from Krishna river using trucks, mini trucks, passenger auto-rickshaws and even bullock carts on both sides of the river Krishna in Krishna and Guntur districts.

Nearly 40 sand reaches are located along the Krishna river in the district from Jaggaiahpet mandal upstream of Prakasam barrage to downstream of the river in Avanigadda mandal in Diviseema.

Sand smuggling is a regular phenomenon in Ibrahimpatnam, Kanchikacharla, Nandigama, Chandarlapadu, Jaggaiahpet, Penamaluru, Thotlavalluru, Challapalli, Ghantasala, Pamarru and Avanigadda mandals of Krishna district.

Besides, sand is also smuggled from rivulets of Munneru and Tammileru in Krishna district.  The officials are facing a challenging task of preventing the illegal sand quarrying. Most of the illegal sand extracted from the reaches is used for construction activity particularly in the construction of buildings, houses, and government projects.

In the Eastern Uttar-Pradesh, mechanized sand mining has resulted in soil erosion and turned thousands of acres of land infertile and sand mafias are in control of rivers like Chhoti Gandak, Gurra, Rapti and Ghaghara.

Indiscriminate sand extraction is likely to create environmental problems in future. The contractors who get the rights for quarrying are exceeding their limits in extracting more sand deep into the river beds.
This will create many environmental problems in future.

Collins et al. (1990) summarized the effects of sand and gravel mining as listed below:

a) Extraction of bed material in excess of replenishment by transport from upstream causes the bed to lower (degrade) upstream and downstream of the site of removal.

b) Bed degradation can undermine bridge supports, pipe lines or other structures.

c) Degradation may change the morphology of the river bed, which constitutes one aspect of the aquatic habitat.

d) Degradation can deplete the entire depth of gravelly bed material, exposing other substrates that may underlie the gravel, which could in turn affect the quality of aquatic habitat.

e) If a floodplain aquifer drains to the stream, groundwater levels can be lowered as a result of bed degradation.

f) Lowering of the water table can destroy riparian vegetation.

g) Flooding is reduced as bed elevations and flood heights decrease, reducing hazard for human occupancy of floodplains and the possibility of damage to engineering works.

h) The supply of over bank sediments to floodplains is reduced as flood heights decrease.


i) Rapid bed degradation may induce bank collapse and erosion by increasing the heights of banks.

j) In rivers in which sediments are accumulating on the bed (aggrading) in undisturbed condition, gravel extraction can slow or stop aggradation, thereby maintaining the channel's capacity to convey flood waters.

k) The reduction in size or height of bars can cause adjacent banks to erode more rapidly or to stabilise, depending on the amount of sand and gravel removed, the distribution of removal, and on the geometry of the particular bend.

l) Removal of gravel from bars may cause downstream bars to erode if they subsequently receive less bed material than is carried downstream from them by fluvial transport.

A worldwide sand rush is taking place. Sand is bagged by divers on the Maldives, it is towed from beaches to trucks by mules in Morocco, excavated from heavenly beaches by machines in the Philippines. In Indonesia dredge boats suck it up from the bottom of the sea, in Vietnam from the river Con. In Sierra Leone workers excavate every grain from local beaches, while on the other side of the Atlantic, in the Caribbean, sand thieves steal entire beaches unnoticed.

Sand is a key raw material for the construction business. Building requires tons of sand. Armoured concrete is two-thirds sand. The construction of a house costs on average two hundred tons of sand. Thirty thousand tons are needed for a one-kilometre stretch of motorway; twelve million tons for a nuclear plant. After water, sand is the most-used material in the world.

Sand for Construction

Sand is an extremely needful material for the construction but this important material must be purchased with all care and vigilance. Sand which is used in the construction purpose must be clean, free from waste stones and impurities. It is important to know what type of sand is beneficial for construction purpose as sand is also classified into three different forms that make it suitable for specific type of construction.

Sand is classified as: Fine Sand (0.075 to 0.425 mm), Medium Sand (0.425 to 2 mm) and Coarse Sand (2.0 to4.75 mm). However this classification of sand is further has types of sand in particular and on that basis only they are being incorporated in the construction. Read out the detailing of the types of sand:

Pit Sand (Coarse sand)

Pit sand is classified under coarse sand which is also called badarpur in common language. This type of coarse sand is procured from deep pits of abundant supply and it is generally in red-orange colour. The coarse grain is sharp, angular and certainly free from salts etc which is mostly employed in concreting.

River Sand

River sand is procured from river streams and banks and is fine in quality unlike pit sand. This type of sand has rounded grains generally in white-grey colour. River sand has many uses in the construction purpose such as plastering.

Sea Sand

As the name suggest, sea sand is taken from seas shores and it is generally in distinct brown colour with fine circular grains. Sea sand is avoided for the purpose construction of concrete structure and in engineering techniques because it contains salt which tends to absorb moisture from atmosphere and brings dampness. Eventually cement also loses its action when mixed with sea sand that is why it is only used for the local purpose instead of structural construction.

There are different standards for the construction purpose which must be checked and considered for the better construction. The requirement according to which sand is chosen should be like:
  • For plastering purpose the overall fine sand used must not be less than 1.5 while silt is preferred to not less than 4 percent.
  • For brick work fine sand used must not be less than 1.2 to 1.5 and silt is preferred is 4 percent generally.
  • Concreting work require coarse sand in modulus of 2.5 to 3.5 with not less than 4 percent silt content.
The coarse sand is used for constructing pillars and underground tanks, while the medium sand is used for the first layer of plastering and other works. The final finish of plastering includes the use of fine sand. Pit coarse sand obtained from quarries is used in the construction of houses in urban areas of Hyderabad. It is filtered when required for specific uses in construction such as plastering.

Like any other material, there are certain features that determine the quality of sand. Good quality sand should not possess more than 4% of silt content. It should have natural and crushed stone sand. It must be free from organic matter and other dirt particles.

How to check the quality of sand.

Many of us do not know the quality, features, and measurements of good sand. Many builders/suppliers make an advantage of this by providing a cheap rate load and may tell that it is of good quality. However, there are certain ways which help you in knowing the quality of sand. Take some quantity of sand and put it in a glass of water. Shake it well and allow it to settle. If a distinct layer of clay or impurities is formed at the top of the sand, it can be considered as of low quality. The other way of assessing the quality is to add sodium hydroxide or caustic soda to sand solution. The presence of impurities in the sand is detected by the color change of the solution. Clay and silt content present in the sand also affects its quality. Here is another idea for assessing the quality of sand. When you rub the sand sample between damp hands, clean sand will leave the hands slightly stained. If the hands are left dirty, it indicates the presence of too much silt or clay in the sand.

Dwindling sand supplies, rising prices and an increased demand have given rise to a sand mafia. In many countries criminals collaborates closely with corrupt governments and police. In over 8,000 places in India, for example, sand is excavated illegally.

Forty percent of Morocco’s sand trade involves illegal sand that is excavated and immediately sold on construction sites. There, it is used unprocessed to make concrete, a guarantee for future problems. The Moroccan government fears that most of its country’s beaches are being transformed into a moonscape.

World status:
 
Singapore – With a booming economy, it has been accused of importing illegally dredged sand from neighbouring states and smuggling sand from poorer neighbouring countries to expand its coast line.

Many islands of Indonesia have vanished.

USA- Sand mining in the USA has resulted in erosion and a collapse of beachfront houses and properties. With beaches disappearing, many places like Florida are artificially putting sand back onto the beaches to attract tourists, but this not been fruitful

Maldives – Many islands have disappeared, there’s been a loss of livelihood and rising water levels Dubai has extensively used and extensively exhausted its own sand resources to build artificial beaches  and in construction, etc. Dubai and many other such countries are buying and importing sand. 

India -
After China and the United States, India has the world’s largest construction business.

India has a very strong sand mafia which works in nexus with builders and politicians, especially in areas like Navi Mumbai, and coastal districts of Thane, Raigad, Sindhudurg and Ratnagiri and Gujarat and Goa. Sand mining and dredging is rampant despite all directives against it.

A lack of any clear regulatory framework has aggravated the environmental problems caused by river sand mining. In addition, sand prices have increased several times over in recent years and this has driven the exploitation of sand into fragile and remote places. This movement of sand mining into marginal areas has not only exacerbated its impact on nature, but has also caused more damage to weak rural roads.

If the demand for sand could be partly met from other sources the environ­mental impact of river sand mining could be significantly reduced. To see whether this is a possible course of action, alternatives to river sand mining were identified and assessed. The following alternative sources were highlighted: offshore sand, land ­based sand, dune sand and the use of quarry dust. A river sand tax could also be introduced in order to encourage the construction industry to move towards the use of offshore sand. But sustainable mining is best option to protect the sands from over exploitation because till today alternatives of sand is not available.

Mother Nature has its own way to counter coastal erosion via a natural supply of sand. Most beach sand comes from rivers that bring it in from the mountains. But exactly these rivers are being dammed up. That effectively stops the migration of sand. Worldwide dams are stopping the supply of fresh sand and are holding up one quarter of the sand supplies. River dredging is another cause why half the sand that would normally reach the sea doesn’t succeed in doing that.

References: 

Collins,B. and Dunne,T. (1990). Fluvial Geomorphology and River-Gravel Mining: A Guide for Planners, Case Studies Included. Special Publication 98, California Department of Conservation, Division of Mines and Geology.











Wednesday, June 18, 2014

Problems of Urban growth.



With special reference to Ranchi city, India.

By
Dr. Nitish Priyadarshi.
Geologist.
76, circular road, Ranchi-834001
Email: nitish.priyadarshi@gmail.com






Night view of Ranchi city.

Abstract:

Owing to population growth, poor levels of hygiene, and increasing urban poverty, the urban environment in many developing countries is rapidly deteriorating. Densely packed housing in shanty towns or slums and inadequate drinking-water supplies, garbage collection services, and surface-water drainage systems combine to create favourable habitats for the proliferation of vectors and reservoirs of communicable diseases. Ranchi the capital city is expanding both vertical and horizontal resulting in lots of problem like irregular electric supply, water supply, ground water depletion, air pollution, noise pollution, municipal waste disposal, failure of drainage systems, traffic jams etc. Surface waters are being contaminated. Seasonal diseases have also multiplied.


Introduction:

As more and more people leave villages and farms to live in cities, urban growth results. Urbanization occurs naturally from individual and corporate efforts to reduce time and expense in commuting and transportation while improving opportunities for jobs, education, housing, and transportation. Living in cities permits individuals and families to take advantage of the opportunities of proximity, diversity, and marketplace competition.
People move into cities to seek economic opportunities. In rural areas, often on small family farms, it is difficult to improve one's standard of living beyond basic sustenance. Farm living is dependent on unpredictable environmental conditions, and in times of drought, flood or pestilence, survival becomes extremely problematic.

Cities, in contrast, are known to be places where money, services and wealth are centralized. Cities are where fortunes are made and where social mobility is possible. Businesses, which generate jobs and capital, are usually located in urban areas. Whether the source is trade or tourism, it is also through the cities that foreign money flows into a country. It is easy to see why someone living on a farm might wish to take their chance moving to the city and trying to make enough money to send back home to their struggling family.

There are better basic services as well as other specialist services that aren't found in rural areas. There are more job opportunities and a greater variety of jobs. Health is another major factor. People, especially the elderly are often forced to move to cities where there are doctors and hospitals that can cater for their health needs. Other factors include a greater variety of entertainment (restaurants, movie theaters, theme parks, etc) and a better quality of education, namely universities. Due to their high populations, urban areas can also have much more diverse social communities allowing others to find people like them when they might not be able to in rural areas.

Clearly, urban settlements differ greatly in size, as mentioned by their populations. Is there a Theoretical maximum and an optimum size? Criffith Taylor and others believe that the ultimate size may be fixed by the increasing difficulty of obtaining enough water to supply unduly large numbers concentrated in a small area, while Lewis Mumford and similar authors think that the continued growth of very large cities not only produces more administrative problems than benefits. This also paralyses rather than furthers social relationships and phenomenally raises central land values, so much that land ceases to be adaptable to new needs.

Views on the optimum size of a city have altered with the march of history. Plato believed that most desirable size was 5,000, a figure which would allow everybody to hear the voice of an orator and so participate in active political life and develop varied social relations. Late nineteenth – century garden city enthusiasts in Britain thought that towns of 30,000 to 50,000 would be large enough supply all necessary human needs, whether medical, educational, social, economic or cultural.

Towns could not come into being until the surrounding countryside was capable of providing a food surplus in the past. Due to modern transport and large surpluses in many parts of the world, towns generally have little difficulty in obtaining food, even from far distant lands. Developing countries may lack the capital to give all their town folk an adequate diet, and even in developed countries there are sporadic temporary shortages, owing to failures in economic planning, poor harvests, dock strikes and traffic hold-ups occasioned by excessive rain, snow, floods, droughts etc.

The problem of water supply is more permanent and applies specifically to cities. It is becoming increasingly serious even in advanced countries which certainly have no problem in paying for the water they consume. The root of the problem lies in the fact that 98% of the earth’s surface water is contained in the salt oceans and in ice-caps. The remainder is unevenly distributed and often polluted. Over half is needed for agriculture, about a third for industry, 10 percent for domestic use.

Many cities, especially in developing countries, lack a clean supply of fresh water. In India, e.g., less than a third of the urban population has access to pure water, and the main reason why water borne diseases are rampant. Even when people are provided with purified water for drinking, they usually wash themselves and their clothing in contaminated supplies.

Owing to population growth, poor levels of hygiene, and increasing urban poverty, the urban environment in many developing countries is rapidly deteriorating. Densely packed housing in shanty towns or slums and inadequate drinking-water supplies, garbage collection services, and surface-water drainage systems combine to create favourable habitats for the proliferation of vectors and reservoirs of communicable diseases. As a consequence, vector-borne diseases such as malaria, lymphatic filariasis and dengue are becoming major public health problems associated with rapid urbanization in many tropical countries

Another change that has occurred after the oil crisis of 1973 is the vertical growth of large cities. People who were living in suburbs found it costly to travel to the city. The open spaces within the city got filled up by the construction of high rise buildings. Large bungalows and old residences were demolished and high rise buildings have come up both as commercial complexes and as residential flats. Many rich families are migrating from the suburbs to flats or apartments near the city centre. The vertical expansion of cities poses further problems in water supply, sewage disposal and traffic congestion on the roads. Traffic causes urban noise, air pollution, stress and strain in an individual.

Urbanization results in construction of a large number of buildings, more roads factories, parking places, etc. for all these, land is secured either by diverting agricultural land or by cutting forests. There may not be one example where a large urban centre has been developed on barren land. It is always the agricultural land or forest land which is utilized. At some places beaches, lakes and rivers are filled to create land to accommodate the growing population. In these cases too, natural habitat is disturbed or destroyed.

Urbanization also introduces new types of plants and animals. When human beings occupy any area they prefer to those animals and plants which are of immediate value. For example, dogs, horses, cows and other domestic animals, are maintained. Parks and garden are created where plants of ornamental and economic values are cultivated. There is also another class of animals, which automatically start living in areas which are occupied by humans. There are rats, crows, mosquitoes, houseflies etc. 


The demands made on water by urban industries, power stations and homes are growing at a more rapid rate than the growth of population. Many wells do not yield enough water, river pollution, like Ganga, Damodar etc. in India, is a continuing evil, and the remaining water resources- mostly in thinly populated highland areas of abundant rain- are far from many consuming centres.

Objectives:

  1. To understand the problem of the Ranchi city due to population growth after becoming capital of Jharkhand state.
  2. To enhance equal and good environment planning on every aspect of development in Ranchi city.
  3. To create awareness of water contamination and water depletion.
  4. To examine the relationship between urbanization and climate change.

Methodology:

In order to achieve the purpose of this paper and to answer the research questions, information was gathered in several ways. These are: field interviews, and field observation . Secondary data also is an important source of information for this paper which was collected through local news papers and web sites.


Case study of Ranchi.


Ranchi is located in the southern part of the Chota Nagpur plateau, which is the eastern section of the Deccan plateau. Ranchi is known as the "City of Waterfalls" because of its numerous waterfalls, the most well known of which are Dassam Falls, Hundru Falls, Jonha Falls, Hirni Falls and Panchghagh Falls.
The Subarnarekha river and its tributaries constitute the local river system. The channels Kanke, Rukka and Hatia have been dammed to create reservoirs that supply water to the majority of the population.
Ranchi has a hilly topography and its dense tropical forests a combination that produces a relatively moderate climate compared to the rest of the state. Although Ranchi has a humid subtropical climate, its location and the forests surrounding it combine to produce the unusually pleasant climate for which it's known. Its climate is the primary reason why Ranchi was once the summer capital of the undivided State of Bihar and was designated a preferable "hill station". Since that time, rapid population growth and industrialization have caused a marked change in its weather patterns and an increase in average temperature. This has resulted in gradual loss of its eligibility for "hill station" status

Demographic history of Ranchi shows that its population grew slowly during 1901-1941. In the subsequent decade of 1941 and 1951, its rate of growth was higher than national average. Due to enhanced importance of the city and its environment, people are attracted towards the city, and occupy land for businesses and residential purposes. The decade 1961-1981 saw the highest growth of population due to migration and attraction of people towards the old summer capital of Bihar. Population increased with 82 percent in 1961-71 and 92 percent in 1971-81. Obviously, people occupied the area where they felt secure in terms of education, hospital, infrastructure, employment, etc.

Ranchi started as a small city occupying an area of around 6 sq km in 1869 with a population of approximately 12,000 in 1871. The area gradually increased to 43.44 sq km in 1965, 175.29 sq km in 1985 and eventually stood at 177.19 sq km in 2004.


Geographically Ranchi city is heterogeneous and due to its varied topological features, development process disturbs-land, village forests, and natural resources. Use of land and steep slopes for cultivation, and heavy engineering works can easily activate ecological degradation. Since natural resources are important base for subsistence, some means should be devised for planned use of these resources. Ranchi region needs much more attention due to regular occurrences of deforestation and improper urbanization.

Rapid urbanization has resulted due to several factors. However, natural population growth remains one of the major factors since 1980s.Ranchi City is experiencing a high rate of growth and it is one of the fastest growing cities in India. As per census from 1901 to 1941 the rate of growth was 3.5 percent per annum, whereas it was 14 percent during 1951 to 1971 and 8 percent during 1971 to 2001. After independence, population of Ranchi City in 1951 was only 1,06,849, which increased by over eight times to 8,63,180 in 2001.


After being separated from Bihar, Jharkhand state of India is now fast growing in terms of business. Ranchi the capital city is expanding both vertical and horizontal resulting in lots of problem like irregular electric supply, water supply, ground water depletion, air pollution, noise pollution, municipal waste disposal, failure of drainage systems, traffic jams etc. Surface waters are being contaminated. Seasonal diseases have also multiplied. More and more people are concentrating in the city flats which has raised the land values many fold. Ranchi earlier known as the summer capital has now become the heat furnace during summer. It is all due to the unplanned expansion of the city.

 Expansion of Ranchi city.


 Dams and ponds are polluted.


 Fine dust created by stone mining to fulfill the demand of Ranchi city is affecting the forest cover.




View of Ranchi city from top of the hill.


Some of the major problems of urbanization in Ranchi are 1. Urban Sprawl 2. Overcrowding 3. Housing 4. Unemployment 5. Slums and Squatter Settlements 6. Transport 7. Water 8. Sewerage Problems 9. Trash Disposal 10. Urban Crimes 11. Problem of Urban Pollution.

The sheer magnitude of the urban population in Ranchi, haphazard and unplanned growth of urban areas, and a desperate lack of infrastructure are the main causes of such a situation. The rapid growth of urban population both natural and through migration, has put heavy pressure on public utilities like housing, sanitation, transport, water, electricity, health, education and so on.

Poverty, unemployment and under employment among the rural immigrants, beggary, thefts, dacoities, burglaries and other social evils are on rampage. Urban sprawl is rapidly encroaching the precious agricultural land.

A considerable change in land use has occurred during the last four decades. Change from rural to urban land has been fast as a result shortage of land has led to speculation and increase in land values.

Over the last thirty years, expansion of the urban settlement has left adverse impact on the health of surface water bodies. Apart from the lessening of the numbers (around 300) of water bodies, it has also lead to the shrinkage of wetlands. Now-a-days, residential or business apartments, at the expense of the water bodies, have become a common phenomenon in the city. According to the study the area has from 1960s onwards suffered from substantial decrease of agricultural lands, open spaces, water bodies, along with an increase of settlements. In 1972, the total area under the surface water bodies was only 66.23 sq. km, while in 2010, the area was 62.14 sq. km. The area under the major reservoirs of the study area (Kanke, Rukka, Hatia reservoir) too has undergone shrinkages.

According to Ranchi district Gazetteer published in 1970, “The climate of Ranchi is cool and pleasant. The general elevation of 2,180 feet above sea level gives it a uniformly lower range of temperature than the plains. However, in spite of the high day temperature, the nights are cool and the atmosphere is so dry that the heat is by no means so oppressive as that in plains. About 5 to 6 thunder-storms and nor’-westers occur in April and May and cause refreshing fall in the temperature”. But today climate is changing with rising temperature and erratic rainfall. Earlier Ranchi received rainfall almost throughout the year but the now it has changed.

The urban heat island has become a growing concern in Ranchi and is increasing over the years. The urban heat island is formed when industrial and urban areas are developed and heat becomes more abundant. In rural areas, a large part of the incoming solar energy is used to evaporate water from vegetation and soil. In cities, where less vegetation and exposed soil exists, the majority of the sun’s energy is absorbed by urban structures and asphalt. Hence, during warm daylight hours, less evaporative cooling in cities allows surface temperatures to rise higher than in rural areas. Additional city heat is given off by vehicles and factories, as well as by industrial and domestic heating and cooling units. This effect causes the city to become 2 to 10 degree F (1 to 6 degree C) warmer than surrounding landscapes. Impacts also include reducing soil moisture and intensification of carbon dioxide emissions.

Inhabitants of Ranchi city of Jharkhand state of India are facing acute water crisis. Most of the dug wells and deep wells and the corporation taps of this populated area have run dry forcing people to consume polluted surface water. Extensive deforestation, urbanization and industrilization has led to uneven spread of rainfall, on which the water supply from the dams to the city area is depended. Even the ground water table has been affected due to uneven rainfall. From last few years rainfall due to western disturbances during winter season has shown decline trend. This rainfall earlier used to recharge groundwater which helped to maintain water table in peak summer season.

The process of urbanization and industrialization from last 30 years has caused changes in the water table as a result of decreased recharge and increased withdrawal. Many of the small ponds which were main source of water in the surrounding areas are now filled for different construction purpose affecting the water table. Lots of DEEP- BORING in the Ranchi city has also forced the water table to move down as well as Ranchi plateau consists of metamorphic rocks which are relatively impermeable and hence serve as poor aquifers. They bear groundwater only in their weathered top portion which rarely exceeds 10 meters.

Now the Ranchi air has become highly polluted. Children are suffering from different lungs diseases. Eyes burning while driving scooter or even walking, is now a very common phenomenon. Toxic gases emitted from the automobiles are increasing many folds. Lots of trees have also been cut down for making houses, marketing complexes etc. Due to thin vegetation Ranchi is under the grip of dust pollution. Due to the dust pollution sky above the Ranchi looks pale yellow.

Ranchi topped the list of increase in vehicle registrations in 2001-2002, the largest in buses, cars, taxis, jeeps, two-wheelers and three wheelers were recorded in Ranchi. Transportation (cars, trucks, buses etc.) is responsible for a significant percentage of criteria pollutants, such as Sulfur dioxide, Nitrogen oxides, Volatile organic compounds, Particulates, Carbon monoxide and Lead.

Emissions from an individual car are generally low. Average emission of carbon monoxide from the two wheelers varies from 0.04% to 0.10% and average emission of hydro carbons was 500 ppm in Ranchi city. But emissions from thousands of vehicles plying in the streets of Ranchi city add up, making the automobile the first greatest polluter. Main problem is with old cars especially diesel operated. In fact, driving a car is probably a typical citizen’s most “polluting” daily activity.

Ranchi City has put heavy pressure on the ecologically sensitive areas, due to deforestation and loss of cropped area. Agricultural land is being gradually converted into built-up land for industrial, commercial, residential and others, uses.

CONCLUSIONS:

Theme of the paper is urban growth and its haphazard nature, which is obvious while traveling on the streets of Ranchi. Areas are being converted for urban use without any systematic development plan and without a corresponding investment in infrastructure. Ranchi City is expanding towards northeast and southwest, encroaching adjacent small towns and engulfing rich agriculture land. Ranchi City has put heavy pressure on the ecologically sensitive areas, due to deforestation and loss of cropped area. Agricultural land is being gradually converted into built-up land for industrial, commercial, residential and others, uses. Poor water and poor land management has resulted in urban areas with inadequate services and infrastructure and a corresponding lack of accessibility, that may prove very costly to resolve in future.

One solution for both lateral expansion and vertical growth of a city is to develop satellite towns at a distance of 40 to 50 km from the city. The satellite town will not be a mere residential town to accommodate commuters. Such a satellite town will be both a place of work and a place of living.

References:

Cherunilam, F. and O.D. Heggade, !987. Housing in India, Himalaya Publishing house, New Delhi.