Presentation on theme: "CONTAMINATION OF GROUNDWATER RESOURCES"— Presentation transcript:
1CONTAMINATION OF GROUNDWATER RESOURCES & ITS SERIOUS CONSEQUENCESBy - : SOMSHREE MUKHERJEE1st YearY10UC326LNMIIT, Jaipur.
2The story of water, is in many ways, the story of life itself… Water is a vital natural resource which must be utilized optimally, ‘harvested’, recycled, conserved, prevented from getting polluted and properly channelized for sustainable development
3GROUNDWATER RESOURCES : How it gets polluted There can be several ways by which the groundwater can get polluted. Here, I have covered the two main sources of groundwater contamination.Through non-engineered open landfillsThrough an increment in the soak pit density, resulting from the increasing population of an area.
4In order to study the aforementioned causes of Groundwater pollution, two case studies were done : 1. Contamination of groundwater resulting from increasing density of soakpits due to increasing population.PLACE : Dehradun city2. An open landfill area causing groundwater pollution due to leaching of toxic materials through the earthPLACE : Outskirts of Jaipur city, along Agra Road, near LNMIIT campus.
5CASE STUDY : 1Contamination of groundwater resulting from increasing soakpit density due to increasing population.PLACE : Dehradun city
6HISTORICAL BACKGROUND * According to “Skanda Purana”, Dun formed a part of the region called Kedar Khand.* The city derives its name from “Dehra” or “Dera” signifying temporary abode or camp.* The term “Dun” or “Doon” means the low lands at the foot of a mountain range* Derivation of the term Dun or Doon is stated to be from Dronashram, hermitage of Guru Dronacharya of Mahabharata fame, who sojourned for a season in the village of Devra, situated near Dehra to perform his devotion at a lovely spot at the foothills of the Himalayas.* It is now the capital of the newely carved hill state of Uttarakhand.
7DEHRADUN CITY Location : Topography : Climate and Rainfall Longitude: 78o00’E o10’ELatitude: o15’N o25’NTopography :Sub-montane valley floor with uneven topographic surface and are also dissected by number streams.Southeast trending streams associated with Bindal, Song and Rispana rivers that drain into Ganga, and the northwest-ward flowing streams associated with Asan river that drain into River Yamuna.Climate and RainfallThe climate of Dehradun is generally temperate.Extreme temperature variation. The heat is often intense during summer (max400C) and it drops down to 2-30C during winter.Substantial Rainfall. Average annual rainfall is 2054mm with 75 rainy days.
8Area and populationThe total Area under the municipal city limit is 52 sq. kmTotal Population according to recent census (2001) is Highest population growth rate: 65% (Approximately 50 persons per day)
9# I observed that students are frequently absent from school because of illness at some point of time in the year.# As observed, it so happens that almost every child today has been affected by some water-borne disease (WBD) at some point of their life, be it jaundice, typhoid, dysentery, cholera, amoebiasis, etc.# So I decided to conduct a demographic survey to find out whether these diseases were locality-specific or spread out through the entire city.# For this, I conducted a survey at school, at Doctor’s clinic and also at chemist shops.# They were given questionnaires in which they were asked their age, the WBD that they had had(if any and the year of occurance ) and the locality in which they lived.
12RESULTS–I: Survey at School Distribution of WBD: No specific locality is more affectedSeasonal Variation: Most of the cases of Typhoid and Jaundice occurred during the summer and rainy season.Out of the 208 families, 58 cases from 55 families reported WBD during the past 18 months.WBD Type Distribution23 typhoid23 Jaundice10 OthersAGE Vs. WBDTyphoid and Jaundice seems to be restricted to children below the age of 15 years.There are only 6 cases of WDB among the adults of more than 15 years of age (2 cases each of Amebiosis, typhoid and jaundice only).
13RESULTS–II: Survey at Clinics TOTAL 75 CASES reported at 3 clinics with in 10 days (Mid October, 04)Typhoid = 19Jaundice = 8Others = 48(Others: Gastroenteritis, Diarrhoea & Dysentery)71 (95%) cases of WBD among Children below 15 Years age groupTyphoid and Jaundice in children (<15 yrs) = 18Contrary to the survey at school, incidence Typhoid and Jaundice cases are significant even during this time (i.e. October).
14Conclusions:The WBD is more prevalent among the children of <15 years age.WBD is spread all over the city. No specific locality is more affected.Most of the cases of Typhoid and Jaundice occurred during the summer and rainy seasonHowever, incidence Typhoid and Jaundice cases are significant even during other times of the year.“Since WBD is caused by consumption of contaminated water, therefore, there are sufficient reasons to believe that the Domestic water supplies in Dehradun is contaminated at some stage from source to end users.”
15Let’s have a look at the FRAGILE GEOHYDROLOGICAL CONDITIONS OF DOON VALLEY Doon valley is an inter-mountane piedmont plain between the northern Mussoorie and the southern Siwalik foothills.Sub-surface rocks consists of loosely packed gravel, sand and silty clay layers up to ~600m thick, underlying the gravels, are the sandstones of Siwalik formation.Doon gravels, having primary porosity and permeability, forms the main aquifer in the area.The groundwater is present in multi-layered aquifers under unconfined conditions and is characterized by high infiltration rate.The depth of water bearing zone is about meter below the surface
16DRINKING WATER RESOURCES of Dehradun City Groundwater Resources•Aquifers down to depths of m.• 52 tube wells in the urban areas and 8 tube wells in the rural areas•82mld of water is pumped through these tube wells.Surface water Resources•Perennial sources:1.Bandal river2.Bijapur canal3.Sahanshai canal4.Rajpur canalm these resources
18# As seen in the population explosion chart before, the population of Dehradun city is increasing at an alarming rate per day.# This is resulting in more number of construction of houses and hence there has been a drastic increase in the number of soak pits in the city.# As the population increases, the demand for water also increases and so more and more tubewells are being dug to pump out more of Ground Water .# This may result in a serious condition of contamination of the ground water as shown next, in a schematic sketch model of how excessive pumping from the aquifer and increasing density of soakpits are directly interlinked to groundwater contamination.
19Sketch model of groundwater contamination due to excess pumping
21This case study was done a couple of years ago, and the project as a whole was also presented at the NATIONAL CHILDREN’S SCIENCE CONGRESS on a National Level at Guwahati, Assam.When this project was presented at the district level, the Chief Executive of the Waterworks Department Of Dehradun was also present, and after seeing the alarming figures and photographs, a follow-up action was immediately executed by her, wherein all leakages on pipelines were plugged and also sewer pipelines have been laid all over the city so as to prevent groundwater contamination through construction of excessive soak pits.
22Another major cause of Groundwater pollution is unplanned landfills. This topic crossed my mind while I was on my way from college(LNMIIT) to Delhi by the Agra Road (NH 11) around January 2011, and this is the topic for my 2nd case study.
23CASE STUDY : 2An open landfill area that may cause groundwater pollution due to leaching of toxic materials through the soil.PLACE : Outskirts of Jaipur city, along Agra Road, near LNMIIT campus.
24HISTORICAL BACKGROUND * Jaipur, the pink city was founded in 1727 by Maharaja Jai Singh II, a Kachhwaha Rajput, who ruled from* Jaipur is the first planned city of India and the King took great interest while designing this city of victory.* According to that time, architecture of the town was very advanced and certainly the best in Indian subcontinent.* Still, the neat and broadly laid-out avenues, painted in pink provide a magical charm to the city.* This city of victory really wins the hearts of the people with its splendid charisma.
25Location :* Jaipur is the capital city of Rajasthan, a state in the Northern part of India.* The pink city would have been a part of Thar Desert, if the Aravalli Hills have not separated them.* As a result, Jaipur is located under the kind protection of Aravalli Hills.* Under the terms of geography, Jaipur extends from latitude degrees in the north to longitude degrees in the east.* The city covers an area of sq kms and lies at an altitude of 431 m above sea level.
26Topography:~ The general slope of the Jaipur city and its surroundings is from north to south and then to south-east.~ Nearly all the ephemeral streams flow in this direction. Higher elevations in the north exist in the form of low, flat-topped hills of Nahargarh (587 meters).~ Jaigarh, Amber and Amargarh, which are deeply dissected and eroded. An isolated hillock called “Moti Dungari” upon which an old royal castle exists, is near the Rajasthan University.~ Further in the south, topographical levels of the plain areas varies between 280 meters along Bandi and Dhund rivers in the south to some 530 meters in the north east of Chomu near Samod hills.~ The overall trend is a decline of level from the areas bordering the hills in the north to plain in the south slopes of the plain areas are in general gentle.
27Drainage:~ The natural drainage of the Jaipur city is largely technically affected.~ It shows intense gully erosion particularly in the northern hilly region.Dhund river and Amanishah nala form a fork like drainage pattern in the confluence zone of which the major part of Jaipur city is situated.~ The Amanishah nala, which originates from the western slopes of Jaigarh hills, flows northwards in the upper reaches, turns south and south-west in its middle course and flows towards east with a broad semi-circle.Finally it joins river Dhund further down stream.~ There is another small drainage system in the north foothills which now a days discharges the city’s waste effluents into an artificially impounded lake called the Jal Mahal (Man Sagar).~ Jal Mahal lake is a large cesspool now of effluent waste water changing its profile from muddy water mixed with effluents and sludge during rainy season to a dried large puddle surrounded by parched earthen floor during summer seasons.
28Solid waste management is one of the most challenging issues in urban cities, which are facing a serious pollution problem due to the generation of huge quantities of solid waste.
29In a majority of the urban centers, waste is disposed off by deposition in low-lying areas, and uncontrolled land filling is practiced in most of the cities. The disposal sites are selected on the basis of their proximity to the collection areas, and new disposal sites are normally identified only when the existing ones are completely filled up. In most cases, the waste is simply dumped at such sites and bulldozers are rarely used for compaction at the disposal site
30# Landfills have been identified as one of the major threats to groundwater resources # Waste placed in landfills or open dumps are subjected to either groundwater underflow or infiltration from precipitation.# The dumped solid wastes gradually release its initial interstitial water and some of its decomposition by-products get into water moving through the waste deposit.# Such liquid containing innumerable organic and inorganic compounds is called ‘leachate’. This leachate accumulates at the bottom of the landfill and percolates through the soil.
31ENVIRONMENTAL PROBLEMS RELATED TO OPEN LANDFILLS 1. Provisions for leachate and gas control do not exist, and soil cover is rarely provided except at the time of closure of the site.2. Most of the disposal sites are unfenced and waste picking is commonly practiced, posing problems for controlled operation of the sites.3. The landfills are not lined, compaction of waste is not carried out, and soil cover is also not applied over the waste.4. As a result, the landfills create unhygienic conditions and cause degradation of environmental quality.5. In rainy seasons, rain water percolates through the waste and soil strata and pollutes the groundwater.6. Fly and mosquito breeding take place at the disposal sites.7. Moreover, a smoke nuisance is caused by the unauthorized burning of waste practiced by rag pickers
32The pollution process : How the Groundwater is getting Contaminated 1. When rainfall soaks into waste in a garbage tip it slowly drains through the waste under gravity.2. As it does so it picks up soluble contaminants from the waste itself. This produces a very strongly organically contaminated liquid which is called leachate.3. Most of the contamination is biological (organic) in nature, but whatever soluble contaminants are present in the landfill, the leachate will probably also contain them in small quantities.4. The leachate will also have dissolved methane in it if it comes from a gassing (biogas producing or methanogenic) landfill.5. The leachate will drain away through any reasonably permeable material which exists under the landfill. Although this material below the landfill may do some filtering and further cleansing of the leachate, it can enter the underground strata still in a highly polluting condition.6. Any groundwater which gets polluted will still keep flowing underground and although the ground may help to naturally filter and biologically treat the leachate, eventually the pollution flow may grow and the small extent of a polluted area shown initially may later have to be extended if a growing contaminant plume develops, and nearby water resources including water supply boreholes can be contaminated.
33Schematic diagram for leaching of Contaminated Soil into the Aquifer
34If the Groundwater gets contaminated once, it will probably remain unusable for several generations. Such a loss of something as precious as water is a terrible problem for later generations.
42Moreover, the landfills stand extremely close to the River hence polluting the river water as well. This River water is used for irrigation purposes in the fields and also for drinking purposes in many of the nearby villages
43It spans 1.67km along the Agra Road and almost 0.32 km in width
44~~~ The site is non-engineered low lying open dump, looks like a huge heap of waste up to a height of 12–20 m. Trucks from different parts of the city collect and bring waste to this site and dump the waste in irregular fashion. The waste is dumped as such without segregation, except the rag pickers who rummage through the garbage and help in segregating it.~~~ The extent of contamination of groundwater quality due to leachate percolation depends upon a number of factors like leachate composition, rainfall, depth and distance of the well from the pollution source, the landfill site in the present case.~~~ The gravitational movement of the viscous fluid, leachate is hindered due to the mass of the solid soil matter.With increasing time the viscous fluid penetrates deeper and spread all over a longer distance.
45Jaipur population Census Pop. %± 1981 1,015,200 — 1991 1,518,200 49.5% Let’s have a look at some statistics of the population of Jaipur :Jaipur populationCensusPop.%±19811,015,200—19911,518,20049.5%20012,210,80045.6%Est. 20135,000,000126.2%i.e persons per day came into the city everyday for 10 years from 1991 to 2001.Source: Census of India
46As we can see , that, as the population of Jaipur increases at this alarming rate, the total solid waste that would be produced everyday will go on increasing and hence these landfills will become even worse !!
47* Areas near landfills have a greater possibility of groundwater contamination because of the potential pollution source of leachate originating from the nearbysite.* Such contamination of groundwater resource poses a substantial risk to local resource user and to the natural environment through air pollution, soil pollution and water pollution.* Many approaches can be used to assess the contamination of underground water. It can be assessed either by the experimental determination of the impurities or their estimation through mathematical modeling
48This Agra Road landfill site is non-engineered landfill This Agra Road landfill site is non-engineered landfill. It is neither having any bottom liner nor any leachate collection and treatment system.Therefore, all the leachate generated finds its paths into the surrounding environment. In such conditions only feasible options that could be followed are:(i) Limiting the infiltration of the water through the landfill cover by providingimpermeable clay cover. Due to this lesswater will enter and subsequently less leachate will be generated, thereby reducing the amount of leachate reaching the landfill base.(ii) Extraction of the leachate collected at the base can be done and it can be recycled, so that less amount will enter the aquifer lying below.(iii) Increasing the evapo-transpiration rate by providing vegetation cover over the landfill can also reduce leachate production.
49Let’s have a look at some of the photographs taken of this place while on a journey from Jaipur to Delhi via the Agra road inJanuary 2011
68Direct Consequences to LNMIITians !!! * With the direction of flow of air, the foul smell from the landfill garbage heaps sometimes also make their way into the college atmosphere, polluting it.* The direction of the river branching in the map shows the slope of the land to be from the landfill area towards the LNMIIT campus.* Therefore, the Groundwater flow direction and the surface water flow directions are toward the college campus which is a serious threat to the students living here and also the villages around.* For this, the groundwater quality should be kept under regular monitor so as to check for any changes in the purity levels of the groundwater, so that, if necessary, steps can be taken to control further damage and pollution of the Aquifer there.
69CAUTION !!! IMAGINE !!! If the aquifer is contaminated… Do we have any technology to clean up the aquifer?The micro-organism would grow and multiply. The valuable groundwater shall become unusable.ACT NOW AND SAVE THE CITY FROM SUCH A DEVASTATION