Emerging Urban Issues

8 billion people TODAY, WHAT ARE WE DOING ?

with

the RISE and the FALL

RESEARCH BYRENO : ASHWINI DHAMANKAR | 001718070 | MUD FALL 2014 9 PROFESSOR. FALL 2014 JUDITH RENO | FALL 2014 | ARCH 765 PROFESSOR JUDITH

ASHWINI DHAMANKAR 1

10 8 1 2

COASTAL CITIES MILLION PEOPLE AT RISK INCH RISE PER YEAR

CONTENTS Sea level rising Factors affecting sea level Case studies Sandy hurricane Missisipi River delta What the world is doing Mumbai Introduction to 2005 mumbai floods Open space per person Mumbai’s natural drain: Mithi river Mangroves Concerning issues Conclusion and recommendations

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SOURCES

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SEA LEVEL RISING global mean sea levels have risen by

0.6

feet

annual rate of rise sea levels have risen by

0.13 sea level rise

inches

3.2

over past

20

years

mm per year

10 MOST VULNERABLE COASTAL CITIES MIAMI , NEW YORK , NEW ORLEANS , TAMPA, BOSTON, GUANGZHOU, MUMBAI, NAGOYA- JAPAN, SHENZHEN- CHINA, OSAKA- JAPAN 4

INFLUENCES

MORE EVAPORATION

WARMER OCEANS

THERMAL EXPANSIONS

RISING SEA LEVELS

STRONGER STORMS

CLIMATE CHANGE

Global warming is the primary cause of current sea level rise.

Shoreline erosion and degradation. Rising sea levels allow waves to penetrate further inland, even during calm conditions, increasing the potential for erosion.

The biggest contributors to sea level rise is rising temperatures, which contributes in two ways. Firstly by increasing the amount of water in the water. Secondly, increasing the amount of space the ocean takesup. The hotter the ocean is, the more volume it takes up - the majority of sea level rise is caused by an increase in volume of the first 100m of depth. An increase of just 1% in this part of oceans’s volume would lead to a significant vertical increase.

MELTING OF SNOW AND ICE

fig. illustrating the causes of sea level rise and their relationship with each other http://www.ucsusa.org/sites/default/files/images/2014/09/gw-graphic-sea-level-rise-storm-surge-and-high-tides-magnify-risks.jpg

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ICELANDS IF MELTS

7.2 m GREENLAND ICELANDS

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ANTARTICA ICELANDS

66 m

RISE IN SEA LEVEL

INFLUENCES

Melting of glaciers and polar ice caps:

Ice loss from Greenland and West Antarctica:

Large ice formations, like glaciers and the polar ice caps, naturally melt back a bit each summer. But in the winter, snows, made primarily from evaporated seawater, are generally sufficient to balance out the melting. Recently, though, persistently higher temperatures caused by global warming have led to greater-than-average summer melting as well as diminished snowfall due to later winters and earlier springs. This imbalance results in a significant net gain in runoff versus evaporation for the ocean, causing sea levels to rise.

As with glaciers and the ice caps, increased heat is causing the massive ice sheets that cover Greenland and Antarctica to melt at an accelerated pace. Scientists also believe meltwater from above and seawater from below is seeping beneath Greenland’s and West Antarctica’s ice sheets, effectively lubricating ice streams and causing them to move more quickly into the sea. Moreover, higher sea temperatures are causing the massive ice shelves that extend out from Antarctica to melt from below, weaken, and break off.

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PREDICTIONS sea levels have risen

sea levels will rise

0.9

3.6

feet

feet

Most predictions say the warming of the planet will continue and likely will accelerate. Oceans will likely continue to rise as well, but predicting the amount is an inexact science. A recent study says we can expect

http://www.centerforsealevelrise.org/ http://ocean.nationalgeographic.com/ocean/critical-issues-sea-level-rise/

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since

by

1930

2100

the oceans to rise between 2.5 and 6.5 feet (0.8 and 2 meters) by 2100, enough to swamp many of the cities along the U.S. East Coast.

SDSDSSD

Sandys storm surge extent 2012

Manhattan ModeL Provided by PictoMetry (2009, 2012)

Sandy 2100

SANDY HURRICANE, NEW YORK

“The answer to the oft-asked question of whether an event is caused by climate change is that it is the wrong question. All weather events are affected by climate change because the environment in which they occur is warmer and moister than it used to be.”

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CASE STUDY

Above, modified satellite images show the river’s delta plain as it appears today compared with how much of the region might be submerged by 2100 due to a combination of trapped sediment and rising seas.

The Mississippi River Delta is drowning, according to new research that predicts the surrounding coastline will be inevitably reshaped in coming decades.

http://news.nationalgeographic.com/news/2009/06/090629-mississippi-river-sea-levels/

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WHAT THE WORLD IS DOING

IJBURG, AMSTERDAM Small docks and communal walkways link the floating houses built on a lake in east Amsterdam. Secured by sliding collars to steel pilings, the houses can rise and fall during floods and storms.

http://ngm.nationalgeographic.com/2013/09/rising-seas/steinmetz-photography

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WHAT THE WORLD IS DOING

NEW ORLEANS The 11 diesel pumps housed in another new storm-surge barrier, this one south of New Orleans, can discharge 150,000 gallons of floodwater per second. In operation since 2011, the barrier helped protect the city’s suburbs from Hurricane Isaac’s storm surge last year

RUSSIA Two curved steel gates, each more than 350 feet long, can swing shut to protect St. Petersburg, Russia, from Baltic Sea storms, which have flooded it repeatedly over the past three centuries. Completed in 2011, the gates are part of a 16-mile-long flood barrier that also carries a new highway.

http://ngm.nationalgeographic.com/2013/09/rising-seas/steinmetz-photography

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WHAT THE WORLD IS DOING

MALDIVES A seawall now protects Maale, capital of the Maldives, an Indian Ocean archipelago that is the lowest, flattest country on Earth. By 2100 rising seas may force Maldivians to abandon their home. More than 100,000 live on this island, on three-quarters of a square mile.

WALCHEREN ISLAND, THE NETHERLANDS For nearly a thousand years the Dutch have been reclaiming land from the sea— and occasionally losing some. A catastrophic flood that killed more than 1,800 people in 1953 spurred the country to

http://ngm.nationalgeographic.com/2013/09/rising-seas/steinmetz-photography

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MUMBAI

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Mumbai is the most populous city in India, most populous metropolitan area in India, and the fifth most populous city in the world, with an estimated city population of 18.4 million and metropolitan area population of 20.7 million as of 2011 originally a group of 7 islands; many reclaimed areas are just 5 mtrs above low tide sea level

MUMBAI MUMBAI

Area- 437 Sq.Km; Population-12Million (2001) Population density-29000 per sq-km

664 mm of rainfall in one day as compared to 950 mm of a monthly rainfall “India stats: Million plus cities in India as per Census 2011�. Press Information Bureau, Mumbai (Press release). Press Information Bureau, Government of India. 31 October 2011.

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MUMBAI 2005 FLOODS

MUMBAI

TRANSPORT STATS FACTS: 52 LOCAL TRAINS, 37000 AUTORICKSHAWS, 4000 TAXIS, AND THOUSAND OF LOCAL VEHICLES DAMAGED COMMERCIAL, INDUSTRIAL AND TRADING INACTIVITY FOR DAYS FACTS: 450CRORE TO DIRECT LOSS TO NUMBER OF BANKS, TRADING CENTRE AGRICULTURE FACTS: 5.5 LAKH HECTARES OF LAND SUFFERED CROP LOSSES 20,000 LAND LOSSES DUE TO TOP SOIL BEING WASHED AWAY

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MUMBAI 2005 FLOODS ECOLOGY DISTURBANCE FACTS: MALLS BULT OVER MANGROVE PATCHES RIVERS DESTROYED FOR DEVELOPMENT

UNPLANNED UNCONTROLLED DEVELOPMENT

ANTIQUATED DRAINAGE SYSTEM FACTS: CAPACITY OF CARRYING 25ml/ hr

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OPEN SPACE PER PERSON

Open Mumbai has calculated that Mumbai has just 1.1 square metres of open space—gardens , parks, recreation grounds (RG) and playgrounds (PG)—per person. The city has 2.5 sq km of gardens and parks, 4 sq km of PG and 7.7 sq km of RG. This adds up to just over 14 sq km of open spaces for 12.4 million people; or 1.1 sq m per person. This corresponds to the oftrepeated statistic that Mumbai has

Only 14 sq km of green for 12.4 million people

a poor 0.03 acre of open space per 1,000 people.

Open spaces have been shrinking to dangerous lows in Mumbai, putting tremendous strain on resources and threatening human health.

“Only 6 percent of the total land in the city is made up of open public spaces. Out of this, 45 per cent is partially or completely encroached upon. A citizen of Mumbai gets 1.95 square metre of open space against the international standard of 11 square metre per person,” said Pankaj Joshi of Urban Development and Research Institute

http://timesofindia.indiatimes.com/city/mumbai/You-have-just-1-1-square-metres-of-open-space/articleshow/13585198.cms http://www.governancenow.com/news/regular-story/only-195-sqm-person-open-space-available-mumbai#sthash.tbleK3iL.dpuf

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OPEN SPACE PER PERSON

where are the trees?

Green spaces in Mumbai Devoid of Green spaces http://timesofindia.indiatimes.com/city/mumbai/Only-19-L-trees-in-Mumbai-makes-greens-see-red/articleshow/8658056.cms

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MUMBAI’S NATURAL DRAIN: MITHI RIVER

Mumbai’s existing storm water drainage system has largely contributed in the inundation of the city. The city’s storm water drainage system is basically a complicated system of simple drains and rivers, creeks, drains and ponds. “The network comprises of a hierarchical system of roadside surface drains (about 2,000 km mainly in the suburbs), underground drains and laterals (about 440 km in the island city area), major and minor canals (200 km and 87 km respectively) and over 180 outfalls, which discharge all the surface runoff into the rivers and the Arabian Sea.”Of these outfalls, some drain directly into the Arabian Sea, while others empty into the Mahim creek, Mahul creek or the Thane Creek. Additionally, some out-falls that drain out storm water from the western suburbs empty directly into sea while the water from the remaining ones is discharged into the Mithi River which ultimately joins the Mahim creek.

The Mithi River constitutes a major component of the city’s SWD system.The storm water drainage of the river is encroached upon by a large number of hutments, storages, processing industries, workshops and scrap yards situated along its banks. These settlements make it difficult even to define the path of the river. Direct discharges of the untreated sewage, wastewater, trash from the unauthorized settlements and industrial effluents flow into the river’s course and choke it up, thus raising the level of water during heavy rains. Similarly, most of the other storm water drains carry sewage and dry garbage in summers which clog them and disrupt the natural flow of rain water. Moreover, illegal settlements and reclamation for future development further reduce the existing width of the river they are built on. These result in the “reduction of the river’s natural storage and aquifer recharge.”

http://disastermanagementmumbai.blogspot.com/2009/07/chapter-4-factors-influencing-mumbai.html 20

MUMBAI’S NATURAL DRAIN: MITHI RIVER Major Drawbacks in the Existing Drainage network

The storm water drainage system of Mumbai was built largely in the days of the British Rule in 1860, when the population of Mumbai was merely one-tenth of what it is at present.

The system comprises of about 400 km of underground drains and laterals, built on the basis of the population and weather conditions of the times it was constructed in. This antiquated storm water drainage system is capable of handling rain intensity of 25 mm per hour at low tide. If the rain intensity exceeds 25 mm per hour and a high tide occurs, there is

always a possibility of inundation.

The city’s existing drainage system is designed to tackle a rainfall of normal intensity, with the assumption that there are no significant solids deposits in the drains. This is because the slope of the drains is supposedly designed to generate a self-cleaning velocity in the flow and is thus built to keep flooding relatively rare.

Most of the drains throughout the city have been found to be occupied by a substantial amount of garbage and other solid deposits.

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MUMBAI’S NATURAL DRAIN: MITHI RIVER

Mthi River’s condition worsens every year after year

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MUMBAI’S NATURAL DRAIN: MITHI RIVER

Starting off as seven separate, lush islands it coalesced into a solid landmass after massive land reclamation projects literally filled up the sea and formed the cosmopolitan, integrated city as we know it today.

This city opens itself up to the sea and balances its various megastructures almost miraculously as the millions that inhabit every inch of its available space

http://footnotes.tiss.edu/proofing-the-citys-bulwarks/

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CONCERNING ISSUES

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MANGROVES

Over 37 sq. km. of mangroves existed in Mumbai, largely in the Thane creek, Mahim, Versova, Gorai and Ghodbunder, with sporadic patches in places such as Bandra, Malabar Hill and Colaba. Mumbai has probably

lost 40 per

cent of all its mangroves in the past decade or so, largely because of reclamation

for housing, slums, sewage treatment and garbage dumps. Mangroves clean the air and water and provide a nursery for aquatic animals, but most importantly, they are the only barrier between the mainland of Mumbai and its unpredictable sea.

Fig. The importance of Mangroves

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MANGROVES

Mangroves

Fig. illustrating the mangrove areas in Mumbai

http://mapinduli.wordpress.com/2009/02/13/mumbai-networks/ 27

Required Mangroves

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CONCLUSION AND RECOMMENDATIONS

Side drains are needed for collecting the surface run-off and leading it to a natural stream.

Combination of landscape and drainage is a good technique to remove out water aesthetically.

Ladsape Catch Basins will make the surface permeable and also takes care of the drainage issues. http://www.allstarrtreeandlandscape.com/sitebuilder/images/french_drain_003-233x250.jpg

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CONCLUSION AND RECOMMENDATIONS

1. Introduce drains along roads to avoid street water run off 2. Increase the permeability near the coastal area so that water could be easily absorbed by the ground 3. Increase tree plantation areas to make soil stiff so that it doesnt run off during catastrophic calamities.

4. Improve quality of roads, application of permeable materials for raods which help in absorbing water .

4. Conservation of forested areas and mangroves 5. River clean off for which is a main problem and hence causes water to pull inside the city 6. Improve the capacity, the material and the quality of storm water pipes to be used.

7. Restoration of existing water bodies, natural drainage, resettle the encroachment, enforcement of rain water harvesting etc. to moderate the discharge.

Permeable concrete pavers allow rain and runoff to infiltrate directly into the ground, taking pressure off stormwater systems and allowing capture of runoff which can then be applied to many other uses.

http://www.hotfrog.com.au/Companies/HydroCon-Managing-water-in-the-urban-environment/HydroSTON-permeable-concrete-pavers-138288

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SOURCES

Books: 1. Dutch Dialogues: New Orleans/ Netherlands : Common Challenges in Urbanized Deltas 2. Drawing the Ground- Landscape Urbanism Today: the work of Palmbout Urban Landscapes 3. Water and the City- Risk, Resilience and Planning for a Sustainable Future by Ian White and Rout ledge Publisher 4. Design with Nature by Ian Mcharg Websites and Texts: 1. www.inhabitat.com i. INHABITAT INTERVIEW: Water Architect Koen Olthuis on How to Embrace Rising Sea Levels ii. Global Warming Threats in Just 10 Major Cities Could Cost 9 Percent of the World’s GDP by Mid-Century by Kristine Lofgren

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