Links: Europa Life, Moon Geology, Citizen Activism

Some readings I perused over the past couple of weeks.

1) Our picture of habitability on Europa, a top contender for hosting life, is changing. Jupiter's moon Europa has long been a contender for hosting life. But lately some scientists have expressed their doubts. Europa has an ocean beneath a 20 km icy crust. Geologists now think that the sea floor is not active. They simulated conditions which could generate shallow earthquakes leading to fault movement and exhumation of fresh rock. Reaction of sea water and freshly exposed rocks is necessary for chemical reactions that sustain life. Results suggest an inert sea floor. Another study implied no magmatism on Europa. Rising magma brings with it heat and chemicals. But, could these be transient conditions that we have caught? Maybe there is a cyclicity to Europa's energy flow. Some interesting thoughts in this article.

2) China's Moon atlas is the most detailed ever made. The Chinese Academy of Sciences has released a stunning 1:250,000 scale geologic map of the moon. A decade of research has revealed 17 rock types ( I used to think only basalt!), 81 basins, and 12,000 odd craters! Compiled from orbiting satellites and then sharpened using data from the two lander missions.

3) How Punekars fought for their hill, Vetal Tekdi, to save its ecology. My city Pune has a proud tradition of citizen activism. For the past few years citizens have vigorously protested a road planned along a forested hill slope. This hill has been a life saver for thousands of citizens as a recreation spot. It hosts rich biodiversity and is an important groundwater recharge zone. The Pune Municipal Corporation is insisting on building this road, despite their own reports admitting an adverse environmental impact, and pointing to at best a short term marginal improvement in traffic flow. The fight to save the hill goes back a couple of decades. Shobha Surin has done a good job summarizing this long battle in Question of Cities.   

Is It A Lava Tube?

My latest field geology video is about a small cave in the basalt lava near my house in Pune city. The location is Hanuman tekdi, also known as Fergusson College Hill. The cave is along the slope right behind IMDR canteen. 

Is the cave a remnant of a lava tube, or has it formed by some other process? 

Sound on. Permanent Link - Fergusson College Hill Cave.

You can access this cave by walking along the path starting from the main gate of Gokhale Institute of Politics and Economics. Turn left as you approach the hill and after a few steps look up to the right. 

Visit quickly. As you can see from this photo, rubble from the construction works of water tanks at the top of the slope is slowly spreading and might cover up this cave. I hope not. 

More geology videos soon!

Groundwater Worries: Saving Pune's Hill Slopes

 SCRAP HCMTR - MAKE PUNE A MODEL FOR SUSTAINABLE DEVELOPMENT

I wrote a short note on my Facebook page on Pune groundwater and its growing importance in response to a citizen's petition to save natural recharge areas that occur on several of Pune's hill slopes. There is a proposal for two roads (the petition mentions only one) to cut across these hills, which will result in the paving over of the recharge surface. In the picture below, the roads will be built at two levels across the slopes behind the green and yellow colored building.

 Forested Slopes of Law College Hill

Besides the threat to groundwater, there are other objections to the road, including its outdated route  and its preference for private vehicles over public transport.

Pune nature lovers and others too... do consider signing the petition and help save part of our precious remaining natural heritage.


Cross Posted from Facebook:

A couple of days ago it rained about 75 mm in central parts of Pune. If you consider a 1 sq.km area around your neighborhood, about 75 million litres of water came crashing down in a few hours. If just 2 percent of that infiltrated into the ground, about 1.5 million liters were added to our ground water resource through a 1 sq. km surface area.

Surprised that rock can hold this much water? Those who grew up swimming in the Tilak Tank of old won't be. It was fed by a natural spring. At any one time the pool held about 2.5 million liters of water. The Tilak Tank hole in the ground would have held much more, but excess water was being drained into a nullah. More recently, the Suvarnarekha building on Prabhat Road was demolished, and the builder excavated a hole for a basement. It soon filled up with ground water. It held about 5.5 million liters of water. As the builder started pumping out the water, more kept rushing in. Over a one and half year period up to 100 million liters of water was likely pumped out. All this water held under a few hundred square meter area!

Pune receives about 650 mm of rain annually. That means 260 billion liters of water falls yearly over a 400 sq.km area. How much of that is infiltrating into the ground.. 5 percent, 10 percent, 20 percent? No one knows for sure and the amount will be highly variable across a surface. But we do have an idea how much is being taken out. A recent estimate by ACWADAM, one of the leading experts on local hydrogeology, puts our annual extraction of groundwater to be 3-4 TMC, which amounts to 80-100 billion liters of water. This suggests that we are extracting more than the natural recharge, since ground water levels are beginning to dip at many places.

The Pune dam cluster collectively store 826 billion liters of water out of which 315 billion liters are allocated annually to Pune. Our increasing use of ground water at 80-100 billion liters annually, underscores the critical role ground water is beginning to play in our lives.

It is imperative that we redress the growing imbalance between extraction and natural recharge. We can do this by individual action of leaving ground uncovered around our homes, and also by protecting larger swaths of recharge areas where infiltration rates are particularly high. The Vetal - Hanuman Tekdi slopes have been identified by ACWADAM as an important natural recharge zone. They must be protected from being covered over by concrete by the proposed HCMTR and Balbharati roads.

Please sign this petition for saving Pune's tekdi slopes from being destroyed! Say no to the HCMTR and Balharati Roads.

SCRAP HCMTR - MAKE PUNE A MODEL FOR SUSTAINABLE DEVELOPMENT

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A small addition to the above post. An earlier study by Raymond Duraiswamy and colleagues published in 2009 had identified the Hanuman (Law College) Hill slopes as potential recharge zones. The map below shows recharge potential of parts of Pune as identified using hydrogeologic criteria. The red rectangle (my addition) roughly outlines the hill slopes under threat of being paved over by roads. The study highlights an area inside the red rectangle (Table 20: Balbharati Building) as an ideal site for enhancing recharge and also points out old quarries in nearby places which could be repurposed to store runoff water for recharging the underlying aquifers. Unfortunately, some of these quarries are now being encroached by slums and also being used as dumping grounds for construction debris. 

Source: Raymond Duraiswamy, Vrishali Dumale and Usha Shetty 2009 - Geospatial mapping of potential recharge zones in parts of Pune city.

ACWADAM will be soon releasing a detailed study of the ground water situation of Pune along with maps of aquifers. I will post that information when it is made available.

Geology Photo Contest

The Centre for Education and Research in Geosciences, a geology outreach group based in Pune, is organizing a photo contest. Entry is open to all. The selected entries will be exhibited during their annual Geology Week event to be held in Pune from October 8 to October 12. Last date for entry in September 21 2018.

Brochure.

.. and go to this webpage for details regarding the photo contest: Geology Photo Contest

Please share widely!

Geo Week 2017, Pune

 Geo-Week 2017 Pune

Starting October 9th 2017, a week long geo-activity program for the public is going to be held at Raja Ravi Varma Art Gallery, Ghole Road, Pune.

It is being organized by the Center For Education and Research in Geosciences (CERG) along with Fergusson College, Pune. CERG is a citizen outreach initiative taken by students and professionals from the Pune geology community.

Take a look at the poster.

The inaugural talk by Dr. R. Shankar of Mangalore University will be on October 9th at 11.30 am . The topic is Paleoclimate Studies of Lake Sediments from South India. The venue is Raja Ravi Varma Art Gallery.

There is another lecture scheduled on October 14th  at 7.40 pm by Dr. S. N. Rajguru. The topic is Prehistoric Environment of the Mula Mutha River, Pune. This talk will be held at the Amphitheater on Fergusson College campus.

There is also a geology exhibition, art and essay competitions for school children, earth science themed film shows and a workshop on QGIS. The exhibition is at Raja Ravi Varma Art Gallery, while most of the films will be screened at the Amphitheater, Fergusson College. Check the website for schedule details.

Pune geology and science enthusiasts, share this with your friends and do stop by and support this initiative!

Geo-Week 2017, Pune

On Being On The Lower Rungs Of Science Hierarchy

This made me chuckle: On being a mycologist from Adam Rogers- Proof: The Science of Booze

"It was something even I, an undergraduate who didn't know anything could do", Scott says. " I could go out there and look for stuff" In the space of one anecdote, Scott had become a mycologist. You think you were an iconoclast in college? Try being a tall, gay, banjo-playing fungus major with a microscope in  your dorm  room,  walls decorated with fungal family trees you drew yourself".

and.. this on perceived scientific hierarchy:

Magnified fungi look like alien plants from a 1930s pulp sci-fi magazine cover, or a Dr. Suess illustration rendered by Pixar. Its a weird landscape, not to everyone's taste. 'If you found a new deer, you'd be on the cover of Nature," says John Taylor, a mycologist at UC Berkeley. "If you find a new fungus, you're in the middle pages of Mycotaxon. But we're not bitter".

That last sentiment reminded me of a conversation I had a long time ago. It was during my M.Sc field training week in Central  India. We were walking back to  camp after a long day's tramp through forests and stream beds. The conversation turned to career choices and the merits and excitement  of getting into a science career. One faculty with us reminded us not to expect attention. Most scientists  will live through  a low profile career.  They will meet a small circle of colleagues and peers. Their papers  will be read by a few  handful of others. You need  to accept this and be satisfied that your  choice and your work is adding  incrementally to our knowledge. Don't expect revolutions.

Is there a division in geology between glamorous and less weighty fields? Again, I  am reminded of the situation during my graduate days at Pune University. The geology department there grew out of a hard rock petrology tradition. There were experts galore on igneous, metamorphic rocks, structure and tectonics and field mapping. Sedimentologists studying hard, consolidated, heavily diagenetically altered and cemented rocks were considered real geologists. Working on unconsolidated Quaternary sediments and landforms was looked down upon. Even worse was if you were in the "environmental" field. Dibbling  dabbling with water samples was just not worth the trouble! It's not hard core geology- was the majority voice.

But times are changing.  The recent impetus in studying climate change means that Quaternary sediments and the secrets they hold about past climates and sea level changes is a hot area of research. So are fields like environmental geochemistry, spurred by increasing social awareness and a tougher regulatory regime, geared towards understanding the myriad pollution problems we face today. They attract funding from government grants and younger faculty and scientists are seizing the opportunity and launching their careers on *shudder* ..the unconsolidated stuff..

The Aquifer Underneath My House

... is very prolific.

The photo above taken in March 2012 is of an excavation for a building about half a kilometer away from my home in Pune, India. The developer struck water at around 20 feet below the surface. Water began gushing out of sheet cracks in the basalt rock. Within a couple of days the water level had risen to just a few feet below the surface and then stabilized.

The water level you see in the picture is not the water table but the potentiometric surface. The developer had punctured a confined aquifer. Water in this type of aquifer is under hydrostatic pressure. The puncture or hole is this case creates a pressure gradient and water flowed from the aquifer (high pressure) into the hole (low pressure). It rose until the water pressure at the bottom of the hole equaled the water pressure in the aquifer at which point water stopped flowing out of the aquifer and hence stopped rising in the well /excavation.

In the picture below the red arrows point to the sheet cracks from which groundwater is seeping out.

Indian Rationalist Narendra Dabholkar Shot Dead In Pune

Crushingly sad news from Pune, India. Yesterday morning two unidentified gunmen shot dead Dr. Narendra Dabholkar (pictured on left) who for many years had been the public voice of reason, fighting against the superstition and pseudo-science that permeates Indian society. The murder followed a persistent campaign by Dr. Dabholkar to get the Maharashtra state government to pass an anti-superstition bill.

The International Humanist and Ethical Union has a short article  on Dr. Dabholkar and his work.

I often hear people say that differences in belief systems and ideology must be debated peacefully and not result in violent outcomes. I think that really underestimates the power belief systems like religion have over human behavior. Much violence throughout human history has been because people hold what they see as nonnegotiable belief systems which then piggyback and amplify an inherent human tendency to divide people into an "us versus the other". Letting go of such strongly held beliefs becomes a question of self-preservation.

Besides, there is an economic angle to this too. Godmen and clairvoyants in India rake in enormous amounts of money channeled to them by an adoring gullible public. They have dedicated television channels where long distance blessings can be purchased. " Our daughter has been sick for the last 8 months" - "Make sure to  sew buttons of the same color on your husband's shirt.. Your daughter will be cured" is the kind of profound advice I have heard being given and which the believers willingly lap up.

Dr. Dabholkar's work threatened to put the brakes on this lucrative business.

World Water Day: Water Water Everywhere ...And Shale Gas

Its World Water Day.

Near my house a big site is being developed. The builder excavated a huge pit about 40-50 feet deep for underground parking only to find he had hit a prolific aquifer.

My rough calculations suggest that the hole contains on the order of 15 -20 million liters of water. That sounds a lot but I was struggling to give it a context. Then this morning I read an article on Fracking, Methane and Food Security. Fracking or hydraulic fracturing is the process of injecting shale rock with a mixture of water, sand and chemicals to pry open the shale and release the tightly bound natural gas.

Here is what the article says about the amount of water used by each well being fracked -

 “Every time a gas well is fracked, 4 to 9 million gallons of water are injected into the ground. A single well can be fracked up to 12 separate times, adding up to over 100 million gallons of freshwater used in the lifetime of a well.” (waterdefense.org)

4-9 million gallons injected every time a gas well is fracked. That's on the order of 20 odd million liters of water, as much as is contained in that hole near my house.

My neighborhood is not depending on groundwater right now, but may have to in the not so distant future. Shale gas though will be extracted in the future from wells drilled in rural India, which depends a lot on groundwater. Farmers use it for drinking purposes as well as irrigating their fields. The gas will be in sedimentary formations a couple of kilometers below the surface, but the water for fracking will be taken from much shallower aquifers that the farmers rely on for their livelihood.

Each time a gas well is fracked, 20 million liters of water will have to be diverted from aquifers underlying their fields for getting the natural gas out. Over the lifetime of a well over 400 million liters of water may be consumed by one well and in an area few tens of sq km, there may be scores of such shale gas wells.

Its early days in our goal to exploit shale gas from various Indian sedimentary basins. Let us quantitatively assess the state of our aquifers besides exploring for shale gas. Let's educate our farmers on how much water shale gas drilling is likely to use up. The residents of central Pune can afford to pump all of 20 odd million liters of groundwater away and still see water gushing out of their taps.

Farmers in the dusty hinterlands may not afford that luxury.

Planting Trees Will Provide Clean Air To Pune?

Pune has several hills scattered throughout its extents. About 1600 odd hectares of them going by the various sources. Some of the hill land is owned by government and is managed by the forest department, some is government owned and is covered by slums and some is under private ownership.

There is a grand plan to convert all or most of this 1600 odd hectares into bio-diversity parks. While the idea of setting aside large swaths of hills as open spaces is creditable, reporting by the media on the supposed benefits of these parks verges on the side of being silly.

Here are a couple of examples I see again and again in media reports on this issue, most recently in yesterday's Times of India (Nov 12 2010, Pune edition):

Air pollution in Pune is a threat to health and well being. The United Nations recommends at least 12 sq m of green area per person for adequate environment for physical and mental health.

An average family of five will require 60 sq m of green area to survive and breathe. Once it comes up, the BDP's will provide clean air for approximately 35 lakh people.

BDP's are the bio-diversity parks and 35 lakhs equals 3.5 million.

Reading this strange environmental calculus makes me wonder how people in Tokyo, Hong Kong, Dubai and Las Vegas, cities with either hyper dense populations or ones bereft of any greenery manage to live healthy lives.

Going by the U.N criteria as presented in the Times of India (TOI) all the people in these cities should be diseased wrecks by now.

The fact is that the greening of the hills will not make a dent in either offsetting carbon dioxide emissions or preventing other types of air pollutants. Pune by a rough estimation of the number of vehicles (approaching 2 million) likely emits more than a million tons of carbon dioxide a year from vehicles alone (here is another estimate). There are other sources that add to this.

1600 hectares of the Utopian forest that may or may not come up on these hills will sequester at most a few thousand tons of carbon dioxide per year. That is the best case scenario. Most likely the number will be disappointingly smaller. Currently the forest on these hills sequester a few tens of tons per year according to this study on carbon sequestration in Pune.

Besides trees don't suck in particulate matter and sulfur and nitrous compounds which have ill effects on health. More than CO2, these pollutants pose an immediate threat to our health. These continue to be emitted in large quantities mostly as vehicular emissions and tree plantations won't reduce their presence in the air above Pune.

I would like to see at least parts of these hills being left as open spaces..there are clear benefits in terms of providing cool recreational spaces for citizens and as a refuge for the urban bird and animal populations. But whether those hills are left barren or are built upon or are completely covered by trees won't make a difference in terms of providing clean air to the city.

That will happen only through cleaner and more efficient use of energy sources particularly a move towards cleaner vehicular fuels.

Sinking Deeper And Deeper For Groundwater In Pune

This is a sight becoming common in Pune.


A drilling rig is often the first order of business for many new constructions on commercial and residential premises. It reflects both an increased consumption of water due to affluent lifestyles and a growing uncertainty about water security often due to lack of piped water supply especially in the suburbs and despite claims from the Pune Municipal Corporation that surface water reservoirs have enough capacity to provide for future population growth and increased use.

I guess people want to ensure that they have a water supply under their control in case of future inability of the city to provide them with piped water. I talked recently with a geologist with years of experience in the groundwater situation in Pune and I heard the same ominous story that is reverberating all over India.

The deeper aquifer in Pune which means drilling to depths of 150-200 feet seems to be experiencing overdraft as unregulated bore-wells extract more than natural recharge. The city is trying to address the problem by proposing that it will limit the number of bore-wells based on surveys of aquifer capacity. This kind of aggregate limit however will not regulate current and future use by individual wells already in operation. Indian groundwater law allows the owner of a property unlimited use of the groundwater and increased reliance on groundwater in the future will keep depleting the resource if not managed scientifically.

And therein lies the problem because just how much water lies underneath is at best only sketchily understood. Any blanket limit going by watersheds  imposed on extraction makes little sense because the deeper aquifers in Deccan basalts are not congruent with the surface water contours. They show extreme laterally variability and are compartmentalized. So for proper groundwater management the underlying aquifers need to be mapped, monitored and a scientific database on aquifer capacity needs to be built before any allocation plan that is sustainable is finalized.

Besides understanding the limits of extraction, just how the city is going to regulate individual use of groundwater remains a thorny issue. There is extreme reluctance to price the use of groundwater by metering bore-wells. The reasons are manifold. It will be an "enforcement headache" (read we are too lazy) is one excuse I have heard. Besides, there is a cultural tendency in India to look at groundwater as a free resource. The focus for long on groundwater use as been on rural consumption for agriculture. Making farmers pay a price for electricity and water is considered political Harakiri in India. So politicians keep tip-toeing around making any serious amendments to groundwater law.

Indian cities however are growing and reliance on groundwater by urban users is bound to increase. There needs to be a sensible re-look at groundwater laws for the urban consumer. Water allocation for well owners based on the aquifer capacity, the need to limit new well permits, mandating artificial recharge structures to augment refilling, and getting urban consumers to pay for the water they are pulling out of the aquifer are all ideas that need to be debated and thrashed out if we want to move towards a more sustainable use of this resource.

Groundwater Flow in Basalts, Caught on Video

The volcanic rock basalt underlies the city of Pune and much of the state of Maharashtra. Its rock mass is made up of an interlocking fabric of crystals and it doesn't have interconnected pore spaces through which water could be transmitted. The permeability of the rock mass is negligible. But basalts can be prolific aquifers. The reason is the various kinds of fractures and joints that serve to store and transmit water.

I came across a construction site near my house the other day and saw that they had dug a pretty deep hole for a foundation. I could see a thick rock profile consisting of two basalt flows. The upper flow was an amygdaloidal vesicular basalt. The lower one was a compact basalt. These are field terms used to categorize flow units with different physical characteristics. At the junction of the two flows was a fractured zone. The fractures were horizontal giving the basalt a sheeted appearance. And water was flowing out of these fractures at a fair pace. Take a look.

Groundwater flow in Basalt

This narrow flow zone which is a few feet thick is really the aquifer in this case. The compact basalt below forms the base of the system. Above this water seep you can see that the amygdaloidal basalt is bone dry. I wrote before about the enormous influence basalt hydrology has on the lives of Maharashtra farmers. You can get an idea why that is so. Finding water in basalts can be tough work because of such narrow permeability zones. Farmers often have the misfortune of farming tiny plots of land over basalts with no or very deep permeability zones. Digging wells into basalts is expensive and risky. Without proper geological guidance many poor farmers remain without access to groundwater.

So far this shallow groundwater system is not being exploited as a resource within the city of Pune. But that might change. Looking twenty years ahead, an expanding population and more water intensive life styles as people become prosperous might strain the surface water supply, which currently is sufficient to give citizens of Pune one of urban India's highest per day per capita allowance of around 200 liters.

Add to that are the vagaries of the monsoons. Even without global warming induced perturbations to rainfall, Indian monsoons are characterized by a decadal scale natural variability. Pune over the last 3-4 years has experienced higher than average rains but extended periods of lower than average rainfall is also a likely scenario in the future. A combination of lower rainfall and higher population might mean that the surface water reservoirs fall short of supplying enough water. The aquifer underneath Pune might gain importance in this context.

Unfortunately hydrologists don't really know how much water is present in the aquifers underneath Pune. The state ground water board periodically issues completely useless statements about the level of groundwater either going up or going down by said amounts. These are based on a few observation wells in areas where the aquifer is not being exploited. But there is practically no quantitative assessment of what will happen to the groundwater system if people suddenly start sucking water out of it. The system has not been studied under stress.

There is an opportunity to do that. On the outskirts of the city private water suppliers have sunk dug wells and bore wells. Year after year they are pumping water out of the shallow and deep aquifers. The water balance is not understood. How much should be taken out so that natural recharge will balance extraction? But I don't see government scientists rushing with their measuring tools to take advantage of these potential data points. Scientific progress relies as much on opportunism as on any other attribute. But state hydrologists lack the flexibility to deviate from their 2 year or 3 year of 5 year plans and schemes they are directed to follow.

Pune must have a science backed plan if and when the time comes to start exploiting the underlying aquifers. The time to start a serious research program is now.

Accessing the Shallow Aquifer Under Pune City

The second phase of the monsoons which normally hit Pune by mid July early August may fail. I read a few days ago that the Pune Municipal Corporation (PMC) fearing a water shortage has plans to tap the shallow ground water aquifer by sinking 500 odd tube wells all across the city. Ground water is available at depths as shallow as 20 odd feet under many parts of Pune city. This shallow aquifer occurs in the basalt lava flows of the Deccan volcanic province. The aquifer has different characteristics which vary laterally and with depth. Dug wells which were an important source of water several decades ago offer the best view of this basalt aquifer and its variability. The image below is of one of the few remaining dug wells in my neighborhood. I have fond memories of this well. During the annual Ganesh festival the family used to come here to immerse the Ganesh idol on Ananta Chaturdashi day. Great to see it still flourishing, providing water for a local garden. The well is located on the talus slope surrounding small hills. The contact between the talus and the basalt is sharp and unfortunately cannot be seen as the upper talus portion is lined. Just below the lined portion of the well, is the basalt which has a slab like appearance. This is due to horizontal sheet joints. Water is stored and transmitted along these joints.


These days you can see the rocks properties of the aquifer at construction sites which excavate huge holes in the ground to put building foundations. The image below is taken at a construction site on flat ground and shows a very different profile than the first example.



The image shows a thick mature soil grading into a highly weathered basalt at the base. This highly weathered basalt forms the upper part of the aquifer. The weathered basalt grades into fresh basalt which may have horizontal joints like the one in the first photo or may be a more dense compact basalt with vertical joints. Its hard to find a location which shows the entire sequence and I have started taking my camera with me in the hope that a big construction site will show the entire aquifer profile. Meanwhile the figure below depicts the typical shallow aquifer system seen in the Deccan volcanic province.


Source: ACWADAM

I think its a lousy and dangerous idea to use this shallow water resource in the manner PMC is proposing to. The corporation simply intends to sink tube wells and install hand pumps and let citizens especially those living in slums access to this water without making any provisions for checking its quality. Unfortunately we know very little about the quality of this water. Likely sources of contamination are leaking and broken sewage pipes and seepage of surface pollutants.The section on groundwater in the environmental status report of the PMC shows that the water has not been screened for the presence of metals, microbes and even fecal matter which is very likely present especially in the groundwater underneath slums which often have no sanitation facilities. Without proper treatment any use of the water in the shallow aquifer constitutes a health hazard.

Pune is luckier than most big cities in India in having an adequate water supply during normal monsoon years. The PMC claims to supply about 200 liters per capita per day. This is much more than most cities in India. There are several big surface reservoirs with capacity to meet projected demands over the next few decades. Pune is growing fast and the problem in recent years has been the delays in setting up water supply infrastructure. Construction of water supply pipelines lags behind buildings, sometimes by years. Suburbs and shanty towns come up either without piped water facilities or with pipes too narrow to supply adequate water, leaving citizens dependent on groundwater which they extract from the deeper aquifer (100 feet or more) or buy from providers who tap it.

But the wild card in coming decades is the reliability of the monsoons. If rains become erratic due to climate change then Pune may be forced into tapping the shallow groundwater system to supplement surface water. This should not be done haphazardly like the current proposal. There needs to be a science backed plan which regulates not only the quality of water taken but also strikes a balance between extraction and replenishment. The deeper aquifer is already showing signs of degrading as unregulated extraction has resulted in an overdraft of several meters over the last decade. That means extraction exceeds natural replenishment with the result that ground water levels are falling year after year. The shallow aquifer if similarly exploited will also diminish quickly as a water resource.

My Five Minutes of Fame As Citizen Activist

I have been profiled in the Times of India, Pune edition. Check out this piece in Times e-paper. You may have to navigate to page 6 of July 25th issue once the e-paper downloads: Switch off at signals, save fuel


Almost a year ago I wrote a series of posts on air pollution and environmental problems facing Pune City. At that time my blog was virtually anonymous. A few friends knew I had started blogging, but the site meter counter moved only occasionally. Still, I like writing about science and I was curious about air pollution in Pune and I kept writing. I really had no expectations about the reach and effect those posts might have. I had underestimated badly the power of the Internet search:

how much CO2 emitted during vehicle idling
bus pollution graphs
comparing diesel and CNG emissions
forest CO2 sinks

These search phrases I can say changed the profile of my blog. I have had several thousand hits on those Pune City posts and hundreds of clicks on the images of the graphs and tables, which have most likely been downloaded. If at least part of the role of a science blog is outreach and education, then I am satisfied with the role my blog is playing. Last month a reporter from Times of India stumbled upon those posts and interviewed me. The article was published today. I don't expect editorial control over the content of the article, but I wish a draft had been sent to me before publishing. The article covers only one of the posts I wrote and I felt a broader coverage of my posts would have helped highlight the entire series. I think its best readers refer to my posts on these topics. Links below:

Part1. Idling and Pollution
Part2. PMT buses and Pollution
Part3. Rickshaws and Pollution
Part 4. Urban Forests and Clean Air
Part 5. Sensing Corruption Remotely
Part 6. Diets, Consumption and Global Warming

I like writing about the city I live in and the neighborhood I grew up in. Being profiled like this is always welcome but I will keep writing about local issues regardless.

Those City Water Wells

Last week I came across a small report on groundwater levels in Pune and finally got down writing about it. The caption read: "Well" done! Water table has gone up in Pune. I am not sure how much significance to assign to this euphoric caption and particular findings detailed in the press report. One usual quibble I have regarding reports such as these is that a meaningful comparison and context is never given. Water table has gone up compared with what? The last measurement? A five year average? A ten year average ? What is the variation shown by the groundwater system over the last 100 years and how does this latest data point fit in? There are apparently some old observation wells that the Groundwater Survey and Development Agency (GSDA) monitors. This forms the basis of these periodic announcements of water table levels. The city has grown enormously over the last few decades and extrapolating from these few monitoring wells to the entire city does not seem to me a very sound idea. Basalt aquifers such as the ones that underlie Pune are quite heterogeneous in their groundwater transmissivity and storage capacities. What is happening to the water table in a few observation wells may not apply some distance away. Without understanding the variability of the system and its causes, simply reporting that the water table has gone up or gone down by a certain amount makes little sense.

The wells referred to in the report are shallow dug wells, which lots of old bungalows used to have when I was growing up in the 1970's. There are still some 5000 odd remaining according to the news report. I remember peering over the side to see how deep the wells were. The water table was shallow about 15-20 feet below surface and the wells always had plenty of water. But even then they were not being used as a drinking water source. Their use was for washing and for the garden. On Ananta Chaturdashi day many well owners used to let neighbors use the well for immersion of their Ganesh idol. It used to be quite a festive occasion. Over the last 3 decades or so their use as a water resource within the city has declined as the water has got more polluted. Still as a geologist I don't miss an opportunity to peer over the side. These dug wells tap the shallow groundwater system in the basalts. Image to the left below is a photo of a dug well I took a couple of days ago. The image to the right is a schematic which shows the hydrogeology of these wells (Source: ACWADAM).





















In the photo you can see that the well is lined. Below that level is the basalt rock which has a slab like appearance. That is due to horizontal sheet joints or fractures along which groundwater flows. Basalt is a volcanic crystalline rock which has a tight interlocking crystal fabric. Water is not stored and transmitted through the rock matrix i.e. spaces between crystals but along cracks and fractures that develop in the basalt. Vesicular amygdaloidal basalt is a type of basalt that has horizontal sheet joints. Another type of basalt known as compact basalt usually develops vertical joints. Basalts with horizontal sheet joints have higher transmissivity and storage capacity and yield more water than compact basalt. These controls are shown in the schematic in the figure to the right (above)

This shallow groundwater system within the city is underutilized today. The trend has been to fill up these wells as bungalows make way for bigger apartment complexes and to bypass the shallow system and tap the deeper aquifers using bore-wells. Many new apartment complexes have bore-wells and utilize the water for washing and the garden. There is an assumption that this deeper aquifer contains cleaner water but that might not always be true. As the graphic to the left shows (source: ACWADAM) deep aquifers are replenished through the shallow system by penetrating vertical fractures. There is a real chance of contamination of the deeper system as well and using that water without adequate treatment is a health risk.



The population of Pune metropolitan area today is around 3 million or so. The city is fortunate to have lots of big surface water reservoirs (Khadakvasala, Panchet, Varasgaon) and the water supply per person is about 2oo litres per day according to the Pune Municipal Corporation Env. Status Report 2004. These reservoirs have adequate capacity to meet projected water demands over the coming decades and the PMC claims to be building water supply infrastructure to supply a population of about 6 million by 2025. Besides surface water the Municipal Corporation keeps talking about using these groundwater aquifers as a supplemental water resource to be used for non-domestic purposes. Rain water harvesting, artificial recharge of aquifers, sustainability, these are the latest buzzwords the city government likes to throw around. But I see two problems for any sustainable use of these systems. The first is a lack of basic science. City officials admit that they don't have any rigorous quantitative estimates on how much water is there and how much extraction is possible given natural replenishment rates. The second problem has to do with how to regulate the use of this resource. Currently groundwater use is not regulated in India and allows the owner of the land to extract as much groundwater as needed. Without changes in the regulatory framework, there will be overexploitation and the danger of degradation of the groundwater system.

Diets, Consumption and Global Warming

Part 6 of the six part series on Pune pollution and environment.

Sometime back a blogger left a comment on one of my earlier blogs, suggesting a number of ways to reduce pollution. Among the many was, "don't drive, walk as much as possible", the rationale obviously being that using less fuel is good for the environment. In these times, when global warming is one of the big talking points, walking is the healthy and responsible way forward. But is it?

A few weeks ago I read a strange article in the Times of London, where a calculation was presented. Apparently if a person walks to the store and around the neighbourhood for errands, let's say around 3 miles or 4.8 km, then providing that person with enough calories to replace those burnt, emits more CO2 than if the person had driven to the store. Driving to the store and back according to the calculation will emit around 0.9 kg of CO2. On the other hand, walking to the store will burn around 180 calories. To replace that with a mostly beef diet will result in 3.6 kg of CO2 emissions. With a straight face the report says “The troubling fact is that taking a lot of exercise and then eating a bit more food is not good for the global atmosphere. Eating less and driving to save energy would be better.” This says a lot about how energy intensive the meat food production chain has become in developed countries. But not just the meat. If you try to replace those 180 burnt calories with milk, it will result in 1.2 kg of CO2 emissions, still more than driving. In 2002, in the United States, the food production system accounted for around 17% of fossil fuel use. Going vegetarian or "vegan"will reduce this burden. Another study has calculated that the difference in greenhouse gas emissions due to shifting to a veggie diet is as much as that achieved by shifting from an SUV to a standard car, a reduction of about 1.4 tons CO2 per person per year. Cutting meat altogether from our diet seems very unpopular at present. Recently, Michael O'Leary, the boss of budget airline Ryanair, came under heavy criticism when he remarked that global warming can be eliminated by slaughtering the world's livestock. Off course going veggie alone doesn't help as illustrated by this cartoon.

I walk a lot in Pune, so do I actually contribute more to global warming by walking and not driving. Suppose following the U.K example I walk around 4.8 km per day and burn about 200 calories. My diet these days is almost entirely vegetarian. Based on a Ford Foundation study on energy intensity of Indian agriculture I calculated that producing 1 kg of food will result in about 2 kg of CO2 emissions. This includes energy required for the entire food production chain including fertilizers and transportation. If I burn 200 calories, eating healthy I would have to eat about 300 grams of various vegetables to make up those burnt calories resulting in about 0.6 kg of CO2 emissions. Much less than the person walking in U.K. and gorging on beef later. Energy intensity of Indian agriculture is still much less than the industrialized food production of the west. If I drive those 4.8 km in my Fiat (that old beast still chugs along) this will result in about 1.15 Kg of CO2 being emitted. But if a person zips around on a two wheeler, driving 4.8 km to the store and back will emit around 0.19 kg of CO2. In Pune, walking over short distances is better than driving a car, but not better than driving a two wheeler when it comes to replacing burnt calories and emitting greenhouse gases.

This will work as long the person maintains a particular weight. If a person starts overeating then all those extra calories represents extra emissions of CO2. This is likely to be a problem in urban India with all the new found prosperity. Trends of weight increase in urban Indians suggest that 40 to 50 million Indians have become overweight over the last few years and it could get worse. To gain one pound a week one has to eat 500 calories extra per day. That is a total of 3500 extra calories. Urban Indians are becoming fat not by eating huge amount of healthy veggies, but by stuffing themselves with calorie rich foods like sweets and oil rich fried stuff. That would mean they will require about 900 - 1000 grams of extra food to put on 1 pound of weight or 20 kg of extra food to gain 10 kg weight. The energy intensity of producing smaller amount of sweets and oil is probably the same as consuming larger amount of veggies. Going by this assumption, that would mean additional emissions of about 230 kg CO2 for every 10 kg of weight increase. If 50 million Indians become overweight by 10 kg that will result in additional emissions of 11.5 million tons of CO2. The figure will be much more if they start eating more chicken, since poultry industry is becoming very energy intensive, western style. My calculations are probably off by some amounts but the intent is to show that obesity and consumption has unexpected consequences.

How are urban Indians doing when it comes to personal lifestyles and the contribution thereof to global warming? Why not find out? Use the personal CO2 calculators I have listen below to calculate how much you contribute to global warming.

Carbon Counter
Conservation Fund Calculator
Carbon Footprint Calculator

To help you out here is a conversion list:

1 Dollar ~ Rs 40
1 gallon = 3.37 litres
1 kg = 2.2 lbs
One unit on your MSEB electricity bill ~ 1 kwhr.
1 cylinder of cooking gas (Propane) ~ 16.5 litres
Fuel Economy: 1km/lit = 2.35 miles/gallon
1000 kg = 1 ton

Compare your emissions with those of households of other nations given below.
CO2 Household Emissions by Country:
Australia - 14 tons/yr
China - 2.4 tons/yr
U.K- 9.8 tons/yr
U.S.- 19.06 tons/yr.

In the interest of full disclosure, I emit about 4 tons per year, a little more I suspect than many Puneites, primarily due to international travel.

This has been a fun series to write. I will be writing on and off about Pune so watch this space.

Part1. Idling and Pollution
Part2. PMT buses and Pollution
Part3. Rickshaws and Pollution
Part 4. Urban Forests and Clean Air
Part 5. Sensing Corruption Remotely

Sensing Corruption Remotely

Part 5 of the six part series on Pune city pollution and environment. Updated every Tuesday.

In this blog I integrate geology and high-resolution images with GIS, to showcase some example of poor urban planning and cases of violation of the urban development plan in Pune. The list of violations of building codes in Indian cities will be quite long. In recent months controversies over whether to build on the hills, and flooding of premises built too close to streams and rivers have caught the public attention. I have highlighted these types of violations since they require some geological knowledge and image interpretation skills to spot. At the end I will discuss some limitations of this approach.

Hill Top Hill Slopes:
Hills are measured in terms of gradient, which is merely the rise of the hill over the run. If you're going up 2 feet for every 100 feet you travel, you're on a 2% hill. For the purposes of urban zoning, the Pune Municipal Corporation Development Plan defines any hill slope with a gradient of 20% i.e. 11 deg or more as falling within a Hill Slope/Hill Top zone (HS/HT). According to the development control rules, owners of plots in HS/HT zones can have a built up area up to 4% of the plot area. Recently, all HS/HT were given protected status and all construction halted.

Construction on steep hill slopes can occur under a number of circumstances.

1) The slope was constructed upon at a time when the area fell outside the limits of the development control rules, i.e. outside PMC limits. This is a common situation in the fringe villages which only recently came under PMC jurisdiction.

2) The slope falls under HS/HT zone and has been encroached upon by slums. This situation is common for HS/HT zones under government ownership.

3) The slope falls under HS/HT zone and constructions have come up as per the development restrictions defined for HS/HT.

4) The slope is reclassified as not falling under HS/HT. Constructions on such misclassified slopes follow normal development control rules. This is a particularly insidious form of corruption of the urban development plan, since the "reclassification" allows plot owners to bypass the 4% rule and construct mansions on hills. Image below depicts this situation.

Source: Google Earth ; Image Copyright: 2007 Digitalglobe ; 2007 Europa Technologies; 2005 Google

The green line is the gentler slope. The yellow line is the steep rocky slope (HS/HT). The orange dotted lines outline a layer of black basalt rock. This layer can be traced from the upper left of the photo where it lies in the HS/HT reserved forest of Vetal Tekdi, along the entire length of the base of Chaturshringi hill. Since the basalt outcrop is horizontal the upper and lower dotted lines are analogous to contour lines. The gradient between them is the same along its entire length and should fall under the HS/HT zone along its entire length. On the lower right however one can observe massive constructions intersecting the basalt layer. The gradient at the site of these construction has been "reclassified" to residential to allow owners to maximize FSI (floor space index).

Encroachments of river banks:
During the recent monsoons, Ram Nadi, a tributary of the Mula river flooded its banks. Water entered the premises of several constructions built close to the banks. Residents, city government and the media suddenly woke up to the fact that these houses were built with scant regard to urban development rules, which mandate a no construction zone of 30 metres near water bodies. Below is an example of a clear violation of that rule. Image shows a section of the Mutha river near the bridge connecting Karvenagar and Sinhagad road.

Source: Google Earth ; Image Copyright: 2007 Digitalglobe ; 2007 Europa Technologies; 2005 Google

I have built a 30 metre buffer along the river banks (green band). River banks are the blue lines. Flow is from right to left. On the south bank (top of image) one can clearly see big apartment complexes falling within the 30 metre buffer. Red arrows outline the unnatural right angle the river bank takes, which means that the river bed has been encroached upon by dumping massive amounts of debris.

Blockage of natural drainage:
Hill slopes have natural drainage made up of small streams. A proper urban development plan should take into account such drainage and not allow constructions to block these streams. However, natural drainage everywhere in Pune has been built upon, simply by filling up these streams. Since during monsoons, water does not find a natural drain, this results in sheet flow of water onto the roads. The erosive power of this water is quite significant, resulting in the famous pot-holes of Pune. Below is an example of natural drainage which has been blocked by several constructions.
Source: Google Earth ; Image Copyright: 2007 Digitalglobe ; 2007 Europa Technologies; 2005 Google

Flow of streams is from left to the right of the image. If one follows the red arrows, you can make out the curvilinear outlines of a small stream which at places abruptly terminates against buildings. This stream joins another stream outlined with blue arrows and forms a bigger drain at the purple arrow. This then flows into the Mutha river. Such blocked streams have only recently caught the attention of the city government, which has promised to amend building rules to allow natural passage of this drainage.

Some technologies such as Google earth allows citizens to locate violations of the urban plan. One can use the distance tools to measure and also draw outlines of objects and save them in a geographic format. These files can be shared with other Google earth users. In this way, citizens can participate in discussions and debates on urban planning without needing expensive GIS software. They can also register complaints with the Municipal Corporation online. But the images are not really a monitoring tool. The images are 6 months to 3 years old. The city government however can use remote sensing as a monitoring tool, if they decide on purchasing high-resolution images every 3 months or so. A one meter resolution image covering Pune municipal limits should cost about Rs. 3-4 lacs. So a purchase budget of Rs. 12-15 lacs a year will give the municipality a powerful urban planning tool not just for spotting violations but also for other urban planning purposes. This off course has to be accompanied by a dedicated GIS staff, in which the city government has shown little inclination and interest.

Part1. Idling and Pollution
Part2. PMT buses and Pollution
Part3. Rickshaws and Pollution
Part 4. Urban Forests and Clean Air

Urban Forests and Clean Air

Part 4 of the six part series on Pune city pollution and environment. Updated every Tuesday.

Tropical forests are extremely important to the global carbon cycle. These forests remove a high proportion of carbon dioxide being emitted by industries and through deforestation. Human activities emit around 25 billion tons of carbon dioxide (CO2) every year. Out of that about 30% is absorbed by the oceans, about 40% stays in the atmosphere and about 30% is thought to be absorbed by forests. Temperate forests are less efficient in sucking in CO2 as compared with tropical forests. But the amount of forest cover is steadily decreasing thus increasing the amount of CO2 that stays in the atmosphere. Deforestation is the second biggest emitter of CO2 after power generation as can be seen in the figure below on greenhouse gas emissions by source (source: World Resources Institute).


In general mature forests are not net absorbers of CO2, since they give up almost as much CO2 through rotting biomass. New growth forests are more efficient absorbers of CO2. So planting trees and expanding forest cover rather than just maintaining forests will lead to offsetting of CO2 emissions.

Right on! Trees as life givers of oxygen (I often wonder why people don't choke to death in deserts), trees as the lungs of our city, save trees and breathe better, all these have become popular slogans. Here are a few more from Pune environmentalists:

"The veritable and venerable lungs of our city".. in this article

"..these green areas give Oxygen....(for us humans..and this is the only source of Oxygen on the planet), help to reduce pollution, and preserve our eco-environment" in this article

and recently (Times of India, Sept 13 07, Pune) by noted environmentalist Anita Gokhale Benninger " An average Pune family size of five people will require 60 sq metres of green areas to breathe and survive. Once preserved and re-forested, the Pune BDP (biodiversity parks) will provide clean air for approximately 35 lakh (3.5 million) people living in this area"

The ability of trees to absorb CO2 has lead to an unquestioned faith in their ability to provide us with clean air. But can trees provide us with that service?

Let's take pollutants that harm us now, and pollutants that will harm us in the future.

Vehicles in Pune emit several hundred to thousands of tons of harmful pollutants like SOx, NOx, HC and PM10 (particulate matter) every year. These are having immediate health effects on citizens. But trees do not absorb these chemicals. No amount of tree plantations will have any effect on the amounts of these pollutants in the air. Ultimately only better quality fuel and to a certain extent a better public transport system will have any appreciable impact on Pune air quality. But trees also absorb dust. Won't that reduce for example the amounts of particulate matter. Ms. Benninger recently calculated that trees in the proposed biodiversity parks will trap around 80 thousand tons of dust per year. The problem is that a large proportion of particulate matter that harms citizens is adsorbed on dust lying of unclean and unpaved roads. Pune Municipal Corporation Env. Status report 2006-07 indicates that nearly 6 thousand tons of particulate matter adsorbed on dusty roads get suspended by vehicular traffic. This is the dust that harms citizens health. The solution for this problem is not trees on hills but better paved roads which are cleaned regularly.

And what about pollutants like CO2, which through its effect on global warming will harm us in the near future? Is the tree cover in Pune offsetting sufficient amounts of CO2 emitted from vehicles? The discrepancy is startling. Here are two examples:

The forest cover on Law College Hill and Vetal Tekdi absorbs about 1.5 tons of CO2 per year. In contrast, idling your vehicle for 5 minutes at Nal Stop every day, will lead to emission of about 625 tons of CO2 per year (amount calculated for total number of vehicles passing through Nal Stop every year).

The total amount of CO2 absorbed by the tree cover in Pune is about 55 thousand tons per year. In contrast, vehicles emit about 2 million tons of CO2 per year.

So Pune tree cover cannot save us from the increasing amount of CO2 emissions either. Increased plantations especially on the hills will help increase the amounts of CO2 absorbed, but I feel they will play no significant role in offsetting vehicular emissions.

Image below shows managed forest on Pune hills.

The second topic I want to briefly touch on is the reporting on the proposed biodiversity parks on the hills. There are complex legal issues involved in this since the ownership of the hills is split between the forest department, the government and private land owners. A significant portions of the hills have been encroached upon by slums. Recently from an environmental perspective the reporting has focused upon carbon trading schemes and whether they can generate funds for land acquisition. The basic idea is to use plantations on Pune hills to offset CO2 emissions and get paid for every ton of CO2 absorbed. Supporters of this scheme say that significant amounts of funds can be generated by plantations on Pune hills. Here is a summary of a recent calculation by Ms. Benninger (Times of India, Sept 13, 07, Pune):

The amount of hill land is 1646.74 hectares. Each forest hectare will absorb around 55 tons of carbon per year. Therefore the total amount of carbon absorbed per year will be 90,530 tons. Carbon credits are presently sold for around $12 per ton of CO2 eq. (my link) and will increase in the near future. So amount of funds generated per year will be around 4.88 crore.

First some technicalities. Some of the hill land is already built upon legally and will in reality never be available for any plantations. Further, is it 55 tons of carbon or carbon dioxide? If it is carbon that means almost 200 tons of CO2 will be absorbed per forest hectare per year (one ton Carbon combines with oxygen to give 3.62 tons CO2). Either way, 55 tons absorption of carbon or carbon dioxide is a gross exaggeration (doesn't the media ever do any background checks?). Amount of CO2 absorbed per forest hectare varies depending on the climate (temperate or tropical) , soil quality, and species of trees. Generally the range is from about 6 tons per year for temperate areas to anywhere from 5 tons to 20 tons per year for tropical areas.

All these amounts are for managed plantations. Currently our forest on various hills (few hundred hectares) are absorbing in totality around 3-4 tons of CO2 per year. This is an abysmally low figure but not very surprising if you are to walk on these hills. The vegetation is stunted and sparse. It sheds leaves starting December and lies bare until the monsoons. By February the forest department starts burning the underbrush as part of their forest management plan. This means emissions of CO2. I doubt if there is any net absorption of CO2 by these forests, especially in the more mature stands. Considering the rocky soils of the hills, no amounts of additional plantations will raise CO2 absorption to a quantity that can generate any significant funds. Besides, environmentalists agree that even the dubious 4.88 crore per year they have calculated is too little an amount for land acquisition, which will require according to estimates several 100 crores.

On this funding issue, the Maharashtra government has been disingenuous. They have transferred the burden of coming up with the funds for the biodiversity parks onto the Pune Municipal Corporation and are refusing to pass the green development plan for the city, which has earmarked the hill areas as biodiversity zones. However, large amounts of money which will unlock land on the hills especially through slum rehabilitation is tied to the Jawaharlal Nehru National Urban Renewal Mission, a central government scheme to modernize Indian cities. The centre will not release that money to the Maharashtra government until they repel the Urban Land Ceiling Act , which the Maharashtra government is hesitating to do. That really should be the thrust of the arguments made by the PMC and environmentalists in the effort to acquire land for the biodiversity parks.

In summary, regarding the biodiversity parks, I feel carbon trading schemes will not generate any appreciable funds. Besides, the very nature of carbon trading schemes through plantations is incompatible with what should be the real goal of the biodiversity parks, which is maintaining and expanding biodiversity. Trading schemes require that plantations consist of rapidly growing trees. Even though indigenous species will be preferred, it would inevitably mean that the plantations will consist of only one or two rapidly growing indigenous tree species, defeating the purpose of developing and maintaining biodiversity.

Trees on Pune hills will not provide citizens with clean air nor will they significantly offset CO2 emissions. The real value of urban forests on these hills is that they provide citizens with open recreational areas, and if properly developed will create expanded habitats for land animal and bird species, thus genuinely contributing to rich urban biodiversity. That by itself is a goal worth fighting for.

Part1. Idling and Pollution
Part2. PMT buses and Pollution
Part3. Rickshaws and Pollution

Rickshaws and Vehicular Pollution

Part 3 of a six part series on Pune city pollution and environment. Updated every Tuesday.

Didn't you see my right foot?! In the middle of an argument over a minor accident the rickshaw driver claimed he had poked his right foot out to indicate that he was turning right. Pune has around 60-70 thousand three wheeler rickshaws. They are no doubt a very convenient form of taxi service. To many harried customers, rickshaw drivers are rude and indisciplined, but I don't really find their behavior on the road to be any different than that of private vehicle owners. This is a country where everyone owns a piece of the road, so rules be damned.

But rickshaws do pollute a lot. Below table shows pollution amounts in tons/year for different pollutants for a total of 62, 600 rickshaws, compared with other vehicle types. Source: Emission factors from S. Guttikunda, World Bank. Rickshaw numbers from N. Iyer, Consultant Bajaj Auto. Values represent combined sum for two stroke and four stroke rickshaws. Other vehicle numbers, from Pune Municipal Corporation, Env. Status report 2005.

As I showed in my previous post, buses pollute more on an absolute basis but are more fuel efficient on a per passenger km basis. What about rickshaws? Below graph shows per passenger km pollution for a trip of 100 kms. It shows that rickshaws pollute more than buses and two wheelers on a per passenger km basis.

Source: Emission factors for CO2, PM10 and SOx from World Bank: A Simple Model for Better Air Quality (2005); N.Harshadeep and S. Guttikunda. Emission factors for rickshaw, S. Guttikunda and N. Iyer.
Assumed Occupancy: 2 wheels-1, Car-2, Bus- 40, rickshaw - 2.

To tackle rickshaw pollution, the Road Transport Authority has made a policy decision to convert existing 2 stroke and 4 stroke petrol rickshaws to natural gas powered vehicles. How much reductions in emissions will be achieved by conversion of petrol rickshaws to CNG? (compressed natural gas). Below table shows reduction in emissions in tons/year for rickshaw and for comparison reduction in emission for PMT buses.

Blank fields indicate lack of data for emission factors. However, SOx emissions are expected to decrease by large amounts for CNG rickshaws.

A conversion of existing fleet of 2 stroke and 4 stroke rickshaws to CNG has the potential to reduce CO and HC emissions by around 95 percent and PM emissions by around 40 percent! There would be significant reduction in CO2 (by about 30,000 ton/yr, or about 20%). Public transport contributes to a substantial portion of total vehicular pollution. My admittedly rough estimates suggest that public transport including rickshaw, PMT buses and private company buses (about 8000 of them according to the municipal corporation) contribute about 40% of total SOx emissions, 30% of PM10 emissions and about 35% of CO2 emissions. Conversion to cleaner fuels will definitely lead to improvements in air quality, especially if the several thousand private company buses are also included. But changing fuel quality of public transport alone may not help in the long run. In Delhi, after significant improvements in air quality due to conversion of public transport to CNG, the latest news is that pollution is on the rise again, due to a heavy influx of private vehicles, many of them running on diesel. Pune faces similar problems with about 6000 new vehicles being registered every month. And with the eminent arrival of the much touted 1 lakh rupee car in the next few years, gains in reducing emissions by cleaner fuels in public transport vehicles may be swamped by the enormous increase in private vehicles. A more comprehensive public transport system needs to be pursued with urgency combined with pricing initiatives to make driving private vehicles more expensive.

Finally some thoughts on six seater rickshaws, those horrendous contraptions, which were banished to the outskirts of the city, because they were thought to be "polluting more". Image shows a six seater in Pune suburbs.

I have to admit I have a liking for these beasts. There is no doubt that they offered frequent and cheap transport services, something that the bus transport has failed to offer. In principle they should not pollute more than rickshaws, maybe even less on a per passenger basis, since on average they carry more passengers. But a widespread use of adulterated fuel and very poor engine maintenance has lead to additional pollution. Here's a thought. Why doesn't the PMT offer their own six seater service? Is it necessary that they offer only a bus service? This way at least the fuel quality can be regulated, and drivers can be trained to obey at least a few rules.

But that would mean thinking out of the box!

Part 1. Idling and Pollution
Part 2. PMT buses and Pollution