Category Archives: Flooding

Protecting the City, Before Next Time

Source: NYTimes

Architecture Research Office and dlandstudio

URBAN WETLANDS A rendering of Lower Manhattan that shows tidal marshes to absorb waves.

Published: November 3, 2012 Arriving in Venice years ago, Robert Benchley, the New York journalist and wit, is said to have sent a mock-panicked telegram to his editor: “Streets flooded. Please advise.”

Related in Opinion

Related in Opinion

Should New York Build Sea Gates?

How can we better protect New York City from flooding?

After the enormous storm last week, which genuinely panicked New York with its staggering and often fatal violence, residents here could certainly identify with the first line of Benchley’s note. But what about the second?

If, as climate experts say, sea levels in the region have not only gradually increased, but are also likely to get higher as time goes by, then the question is: What is the way forward? Does the city continue to build ever-sturdier and ever-higher sea walls? Or does it accept the uncomfortable idea that parts of New York will occasionally flood and that the smarter method is to make the local infrastructure more elastic and better able to recover?

Gov. Andrew M. Cuomo on Wednesday gave a sea wall the nod. Because of the recent history of powerful storms hitting the area, he said, elected officials have a responsibility to consider new and innovative plans to prevent similar damage in the future. “Climate change is a reality,” Mr. Cuomo said. “Given the frequency of these extreme weather situations we have had, for us to sit here today and say this is once in a generation and it’s not going to happen again, I think would be shortsighted.”

The water rose in Dumbo, Brooklyn, on Monday.
Kirsten Luce for The New York Times

The water rose in Dumbo, Brooklyn, on Monday.

But some experts in the field who have thought deeply about how to protect New York from huge storms like Hurricane Sandy — and especially from the coastal surges they produce — suggested that less intrusive forms of so-called soft infrastructure might prove more effective in sheltering the city than mammoth Venetian sea walls. Mayor Michael R. Bloomberg seemed to agree with them on Thursday when he said: “I don’t think there’s any practical way to build barriers in the oceans. Even if you spent a fortune, it’s not clear to me that you would get much value for it.”

According to the experts — architects, environmentalists and civil engineers — large-scale projects like underwater gates are expensive, cumbersome and difficult to build. More important, they say, such undertakings are binary projects that work just fine until the moment they do not.

Whatever the way forward, Klaus H. Jacob, a Columbia University seismologist and an expert on urban environmental disasters, said the century-event of Hurricane Sandy could become, because of rising seas alone, an annual occurrence by 2100.

“We know what we have to do,” said Dr. Jacob, who predicted last week’s tragedy with eerily prescient detail in a 2011 report. “The question is when do we get beyond talking and get to action.”

Among those actions already proposed are relatively minor alterations to the building code, to ban housing boilers and electrical systems in basements, and slightly more apocalyptic strategies, like one known as managed retreat, in which people would cede low-lying areas to the sea. While no one is calling for a mass and permanent exodus from the Rockaways, for instance, some experts, like Radley Horton, a climatologist at Columbia University, said that as parts of New York became more difficult — and costly — to protect, managed retreat needed at least to become “part of the public discussion.”

Here, then, are three proposals — some traditional, some fantastic, but all at least theoretically workable — designed to reduce the effects of storms like Hurricane Sandy on three especially vulnerable New York neighborhoods: Lower Manhattan, the Red Hook and Gowanus sections of Brooklyn, and the northern shore of Staten Island.

Lower Manhattan

Marshy Edges, Absorptive Streets

Picture a fringe of mossy wetlands strapped like a beard to Lower Manhattan’s chin, and you are halfway toward imagining the plan to protect the financial district and its environs dreamed up by the architect Stephen Cassell and a team from his firm, Architecture Research Office, and a partner firm, dlandstudio.

“Our goal was to design a more resilient city,” Mr. Cassell said. “We may not always be able to keep the water out, so we wanted to improve the edges and the streets of the city to deal with flooding in a more robust way.”

Among the most disturbing images to emerge from the aftermath of the storm was that of a pile of cars floating upended in the waters of a parking lot near Wall Street. Lower Manhattan, where most of the borough’s power failures occurred, is vulnerable to floods like this not just because it sits low in relation to the sea; it also juts out on heaps of artificial landfill, into the fickle waters of New York Harbor. It is probably not coincidental that the flooded areas of Manhattan, largely correspond to the island’s prelandfill borders.

To prevent incursions by water, Mr. Cassell and his planners imagined ringing Lower Manhattan with a grassy network of land-based parks accompanied by watery patches of wetlands and tidal salt marshes. At Battery Park, for instance, the marshes would weave through a series of breakwater islands made of geo-textile tubes and covered with marine plantings. On the Lower East Side of the island, Mr. Cassell and his team envisioned extending Manhattan by a block or two — with additional landfill — to create space for another new park and a salt marsh.

Beyond serving as recreation areas, these engineered green spaces would sop up and reduce the force of incoming water.

“When there’s a storm surge, it creates an enormous amount of energy,” Mr. Cassell said. “Wetlands absorb that energy and protect the coastline.”

As a complement to the parks and marshes, Mr. Cassell’s team would re-engineer the streets in the neighborhood to make the area better able to handle surging waves, creating three variations of roadway. On so-called Level 1 streets, asphalt would be replaced with absorptive materials, like porous concrete, to soak up excess water like a sponge and to irrigate plantings in the street bed. Level 2 streets, planned for stronger surges, would send running water into the marshes at the island’s edges and also into prepositioned ponds meant to collect runoff for dry spells. Level 3 streets — the only ones that might require a shift in the current city grid — would be parallel to the shoreline and designed to drain surging water back into the harbor.

“We weren’t fully going back to nature with our plan,” Mr. Cassell said. “We thought of it more as engineered ecology. But if you look at the history of Manhattan, we have pushed nature off the island and replaced it with man-made infrastructure. What we can do is start to reintegrate things and make the city more durable.”

Red Hook and Gowanus

Oysters to the Rescue

The architect and landscape designer Kate Orff based her plan to shield the Red Hook and Gowanus neighborhoods of Brooklyn on the outsize powers of the oyster. “The era of big infrastructure is over,” Ms. Orff said. By placing her faith in a palm-size bivalve to reduce the effects of surging storms, Ms. Orff said, she is “blending urbanism and ecology” and also “looking to the past to reimagine the future.”

Red Hook, Brooklyn, was hit hard last week by flooding from Hurricane Sandy.
Spencer Platt/Getty Images

Red Hook, Brooklyn, was hit hard last week by flooding from Hurricane Sandy.

Red Hook, in particular, was thrashed by Hurricane Sandy as some of the local inlets, like the Buttermilk Channel and Gowanus Bay, spilled into the low-lying area, swamping public housing projects and sending water rushing so high through the streets it occasionally swallowed up cars and bicycles.

Ms. Orff’s proposal., created by a team at her design firm Scape/Landscape Architecture P.L.L.C., envisions a system of artificial reefs in the channel and the bay built out of rocks, shells and fuzzy rope that is intended to nurture the growth of oysters (she calls them “nature’s wave attenuators”).

<strong>WATERWORLD</strong>&nbsp;A reef constructed from rock and shell piles to host oyster growth, as seen in a rendering for a proposal in Brooklyn. Such a structure could filter water and mitigate storm surge.
Scape/Landscape Architecture

WATERWORLD A reef constructed from rock and shell piles to host oyster growth, as seen in a rendering for a proposal in Brooklyn. Such a structure could filter water and mitigate storm surge.


The Bay Ridge Flats, a stretch of water that sits off the coast of the Brooklyn Army Terminal, was once home to a small archipelago of islands that protected the Brooklyn coastline. The islands have long since disappeared because of dredging, and Ms. Orff would replace them with her oyster-studded barriers, which, over time, would form a sort of “ecological glue” and mitigate onrushing tides, she said.

<strong>AQUACULTURE</strong> Oyster beds as depicted in a rendering for a proposal in Gowanus, Brooklyn. The shellfish could be cultivated by community groups and seeded on a planned reef, part of a water filtration and surge-mitigating system.
Scape/Landscape Architecture

AQUACULTURE Oyster beds as depicted in a rendering for a proposal in Gowanus, Brooklyn. The shellfish could be cultivated by community groups and seeded on a planned reef, part of a water filtration and surge-mitigating system.


At the same time, she imagines installing oyster beds along the banks of the Gowanus Canal in a series of what are known as Floating Upweller Systems (Flupsys) — essentially, artificial shellfish nurseries. A powerful fan blows aerated water through a group of eight chambers in which oysters or mussels can be grown. The chambers protect the budding oysters from predators like starfish. Above the Flupsys, Ms. Orff would place a public walkway for joggers and strollers, punctured every so often by hatches that could be lifted to permit a view of the nature below.

“This is infrastructure that we can do now,” she explained. “It’s not something we have to think about and fund with billions of dollars 50 years down the road.”

Oysters have the added benefit of acting as natural water filters — a single one can clean up to 50 gallons of water a day. By being placed in the Gowanus Canal, Ms. Orff hopes, they could further purify what has already been named a federal Superfund site. She wants, by way of her project, to change how we think about infrastructure projects.

“Infrastructure isn’t separate from us, or it shouldn’t be,” Ms. Orff said. “It’s among us, it’s next to us, embedded in our cities and our public spaces.”

Staten Island

A Bridge in Troubled Waters

A rendering of a storm barrier with a drawbridge on Arthur Kill, intended to protect Staten Island in a Category 3 hurricane.
CDM Smith, Inc

A rendering of a storm barrier with a drawbridge on Arthur Kill, intended to protect Staten Island in a Category 3 hurricane.


A few years ago, Lawrence J. Murphy, an engineer in the New York office of the global engineering firm CDM Smith, was asked by the local chapter of the American Society of Civil Engineers to propose a way of protecting northern Staten Island from the forces of a Category 3 hurricane. He came up with a plan to build a classic storm-surge barrier across the Arthur Kill, the tidal strait that separates Staten Island from the mainland of New Jersey, designed to act in concert with similar barriers in the East River, the Narrows and the waters near the Rockaway Peninsula.

Staten Island was ravaged by Hurricane Sandy, as entire neighborhoods were flooded, a168-foot water tanker crashed onshore and city officials said that most of the fatalities in the city occurred there. It is arguably New York’s most exposed borough, surrounded not by peaceful rivers but by oceanic channels like the Arthur Kill and, of course, the Atlantic itself.

Mr. Murphy’s concept, created with his partner, Thomas Schoettle, calls for the construction of a damlike structure with suspension towers spanning the Arthur Kill. Tidal gates below the surface would open and close as needed.

A rescue from Dongan Hills, Staten Island, on Tuesday.
Michael Kirby Smith for The New York Times

A rescue from Dongan Hills, Staten Island, on Tuesday.


According to the Army Corps of Engineers, Category 3 hurricanes (Hurricane Sandy was a Category 1 storm, downgraded by the time it reached New York) would produce surges of slightly more than 14 feet above normal sea levels. Mr. Murphy designed his barrier to protect against “overtopping waves” of an additional 8 feet, for a total height of 22 feet. He also designed a complex system of locks and drawbridges to accommodate the numerous commercial ships that navigate the kill.

Mr. Murphy’s barrier would be run by a trained staff and would operate on emergency power in the event of an electrical failure. Because strong tides pass through the kill, he would also outfit the barrier with tidal generators, which, as an extra benefit, could produce electricity.

Nor did Mr. Murphy ignore the possibilities of public recreation. “The concept design of the Arthur Kill Storm Barrier has been made with a focus on aesthetics to create a destination,” he wrote in his proposal. “The multiuse path can provide bicycling and walking opportunities. Fishing and bird-watching amenities can also be provided.”

A version of this article appeared in print on November 4, 2012, on page MB1 of the New York edition with the headline: Protecting the City, Before Next Time.

Tropical Storm Gaemi to hit Cambodia


Wednesday, 03 October 2012
 Phak Seangly

Infrared imagery from the AIRS instrument aboard NASA’s Aqua satellite captured this image of Tropical Storm Gaemi on Oct. 2 at 0517 UTC. The purple areas indicate the most powerful thunderstorms with coldest cloud top temperatures. The asterisk (*) indicates the center. Photograph: NASA/JPL, Ed Olsen

A storm brewing in the South China Sea will hit Cambodia tomorrow, causing heavy downpours, wind and flooding in up to 13 provinces, the Ministry of Water Resources and Meteorology warned yesterday.

Tropical Storm Gaemi was yesterday a low pressure system about 700 kilometres west of Danang, Vietnam, but will develop into a larger storm, also crossing parts of Laos and Thailand, over the next four days.

Fishermen in Koh Kong, Kep, Kampot and Preah Sihanouk provinces have been told to postpone fishing over the weekend and stay on high alert.

The storm is expected to cross Cambodia tomorrow and depart Monday.

Nak Seng, a fishermen’s representative from Troy Koh commune in Kampot, said some fishermen would venture out despite expected waves of up to 2.5 metres.

“We won’t go far from the shore, and we’ll come back when we see the storm,” he said.

In his announcement, Minister of Water Resources and Meteorology Lem Kenhor said Gaemi would cause heavy rain, wind and floods in the higher-up provinces of  Kampong Cham, Mondulkiri, Ratanakkiri, Kratie, Stung Treng, Oddar Meanchey and Preah Vihear; lower-lying Siem Reap and Kampong Thom as well as Koh Kong, Kep, Kampot and Preah Sihanouk.

Meanwhile, more than 200 families in Banteay Meanchey’s O’Chrou district face emergency evacuation after Thai authorities in the border province of Sa Kaeo were forced to release water from an overfull dam on Monday.

Soung Muon, O’Beichoan commune chief in Banteay Meanchey’s O’chrou district, said that water levels had increased by more than half a metre yesterday as authorities prepared to move villagers to higher ground.

“It doesn’t rain here, but water is increasing a lot. We could assume that it flows from Thailand, and about 200 families might be evacuated soon. We are observing the sutation,” he said.

The National Committee for Disaster Management will revisit the province tomorrow.

To contact the reporter on this story: Phak Seangly at

Flood’s deadly toll contested

Phnom Penh Post

Tuesday, 02 October 2012
 Phak Seangly

Villagers look at the body of a man who drowned during flooding in Banteay Meanchey province on Sunday, Sept.30, 2012. Photograph: National Police

Disputed figures surround the flood death toll in Banteay Meanchey province.

Yesterday, Banteay Mean­chey city hall spokesman Keo Ratanak rejected reports that more than 10 people had drowned in the province as a result of the flooding, saying: “The exact number is seven.”

But according to numbers obtained from other local authorities, including police and district governors, the deaths add up – with three people drowned in Poipet, three in Serei Sophoan, three in Ou’chrov dstrict, two in Phnom Srok distict and two in Mong Kulborei district for a total of 13 people.

The most recent victim, an 18-year-old from Poipet, had been found dead on Saturday, Poipet governor Ngor Meng Chroun said.

Thai authorities in the flood-prone border province of Sa Kaeo informed Banteay Meanchey authorities they might have to release a dam that is filling up after an extended wet period.

“Thailand informed us, so we alerted our people in Ou’chrov district and Poipet town, because they are the two places that will be affected first,” National Committee for Disaster Management’s Keo Vy said.

By yesterday afternoon, Ratanak was still not certain whether Thailand would release the water.

Last Friday, the government announced a low-pressure system would develop until Thursday, leaving 18 provinces, as well as national routes 4, 5 and 6, at risk of flooding.

“The low air pressure can cause rain almost nationwide, so people living in the areas, be careful and take precautions,” the Ministry of Water Resources and Meteorology advised.

Meanwhile, the flooding in Banteay Meanchey that forced 5,000 families to be evacuated and inundated 41,000 hectares of paddy fields, is on the rise again after subsiding early last week.

To contact the reporter on this story: Phak Seangly at

It Rained A Little This Morning

Happy one year anniversary in Cambodia to City of Water!

I have tried, and failed, to really capture the flooding since I moved to Cambodia one year ago:

While driving with a HD Hero 2 Go Pro – here.

With my waterproof camera an Olympus StylusTough-8010 – here – which does well in bright sun but rather poorly in rainy, low-light environment, especially when combined with traffic movement.

One afternoon, I did get some shots on foot near my house with my Nikon D7000 – but that involved several ponchos and plastic bags.

This was a rare opportunity to shoot the flooding from inside a van.

Rainy Phnom Penh

Rainy Phnom Penh

Rainy Phnom Penh

Rainy Phnom Penh

Rainy Phnom Penh

Rainy Phnom Penh

Flood resistance leverage for foreign investment


Thursday, 27 September 2012  May Kunmakara

Minister of Commerce Cham Prasidth (L) looks at vehicles at a new Honda showroom in Phnom Penh yesterday at Honda’s 20th anniversary gathering. Photograph: Vireak Mai/Phnom Penh Post

Cambodia’s Commerce Minister Cham Prasidh said foreign investors with production bases in Thailand ought to consider Cambodia for future expansion because of the Kingdom’s greater resistance to floods.

Speaking at Phnom Penh Honda’s 20th anniversary yesterday, the Commerce minister said that while Cambodia faces floods each year, the floods did not seriously affect most factories and industries.

“Flooding affects only rice fields along the Mekong River – not factories. We also forecast that this year, the floods will be bigger than the last year, and we are trying to curb any negative effects to the economy. Cambodia’s industry sector, which is mostly located away from flooded areas, should not be affected,” he said.

“Cambodia has great business areas, offers a better investment climate and incentives for foreign investors. I do believe that it is a great opportunity for other Japanese companies that have factories in Thailand to consider Cambodia.”

Hiroshi Suzuki, CEO of Business Research Institute for Cambodia (BRIC) agreed that floods did not have a severe affect on Cambodia compared to neighbouring countries, stressing that infrastructure such as roads were little damaged, connections between Phnom Penh, Thailand and Vietnam were not seriously impaired and only the tourism sector in Seam Reap was seriously hampered.

“Fortunately, Cambodia’s industry sector is very resilient to floods. Last year’s floods were the biggest in the 10 years. However, almost all factories were free from damage. Main industries such as the garment and textile sector weren’t susceptible to flooding,” Suzuki said.

He said Japan’s Minebea had begun to expand their factory in Phnom Penh Special Economic Zone, as one example of an industry fairly impervious to flooding.

Suzuki said the damage by flooding didn’t compel the Japanese companies operating in Thailand to plan relocations of factories immediately to the Kingdom.

“In the middle term, some of those factories, especially the labour-intensive parts-manufacturing sector, would consider the transfer of a part of their operations to safer places such as Cambodia, as one of the measure of risk control,” he said.

Chairman of the General Insurance Association of Cambodia (GIAC) Chhay Rattanak said last year’s floods had delayed some construction projects in Siem Reap province as well as the railway project in Banteay Meanchey province worth around $1 million. He hopes that this year the government will be well-prepared to deal with floods.

Last year’s flooding in provinces along Mekong River damaged about 10 per cent of Cambodia’s total crop, compared to more than 60 per cent of crops that were damaged in Thailand.

The Cambodian government spent about US$200 million for the rehabilitation of infrastructure hit by the floods last year. Cambodia has set aside $90 million for 2012 from the national budget against the possibility of flooding.

To contact the reporter on this story: May Kunmakara

Three lives swept away by flash flood

Three lives swept away by flash flood

Thursday, 20 September 2012 Phak Seangly and Rosa Ellen

A villager paddles through the flood, after much of rural Cambodia was inundated for several weeks. Photograph: Sreng Meng Srun/Phnom Penh Post

Three people have drowned and more than 3,000 have been evacuated since flash flooding struck a trio of provinces late last week.

Yesterday, the Cambodian Red Cross said it was mobilising aid and planned to have packages of rice, canned fish, noodles and other materials in the hands of 2,340 families, mostly in Banteay Meanchey, by this weekend.

In the evacuated village of Ou’Bei Chean in Banteay Meanchey’s Ou’Chrov district, the body of a 34-year-old man was found yesterday morning. Commune chief Suong Suon said the man  returned alone to his house while his family was being moved to safer ground.

Ten of the 11 villages in his commune were flooded, Suong said, with 126 families forced to leave their homes.

“Villagers are in need of food and the Cambodian Red Cross plans to distribute food and gifts for the 126 families on Thursday,” he said.

A 59-year-old local drowned in Kampong Thom’s Kampong Svay district on Monday, and a 12-year-old girl drowned in Siem Reap late last week.

Poipet governor Ngor Meng Chroun said officals were still busy moving hundreds from flooded areas, including Poipet City, to properly assess structural and environmental damage.

The Asia Development Bank, which is leading Cambodia’s Flood Damage Emergency Reconstruction Project for last year’s devastating floods, said it wasn’t clear yet what rural road projects had been affected.

“When we considered the Stage Two projects, we selected them on their vulnerability, based on whether they were likely to be flooded again,” deputy director of ADB’s Cambodia mission Peter Brimble said.

If the government did request help for newly damaged infrastructure the bank would look at money left over from existing projects, Brimble added.

About 300 metres of national road under construction has been damaged in Ou’Chov district, authorities reported.

Water has receded in some provinces threatened by flooding earlier this week, but rain is expected through to Sunday.

To contact the reporters on this story: Phak Seangly at
Rosa Ellen at

Historic Flooding National Museum

Two men in a pirogue paddle by the museum entrance. Circa 1934. Photo courtesy Nicole Groslier. Photo 1934. Via Di Dol Facebook.

Toronto Flood Protection Plan

“…landscape architect Michael Van Valkenburgh has taken a novel approach to flood protection, reconfiguring the proposal so flood protection is phased in one area at a time. This also reduces the initial costs..The new $1.9 billion plan moves up the timeline for development..And it means parts of the 400-hectare Port Lands can be sold off for development, with the money used to build flood protection in another area.”

Port Lands development proposal looks ‘pretty darn good’

Published on Wednesday August 08, 2012

WATERFRONT TORONTOAn illustration of the redeveloped Don Roadway shows how the area would look after the renaturalized Don River is directed through the Port Lands area.
Patty Winsa
Urban Affairs Reporter
After dodging a proposal that would have turned the Port Lands into a carnival sideshow, development of the massive parcel of land is back on track.

Waterfront Toronto and the city unveiled the latest vision for the Port Lands on Wednesday, almost a year after it was nearly critically derailed by councillor Doug Ford’s plan to build a Ferris wheel, monorail and megamall.

“This is a silver purse we made out of the sow’s ear,” said Councillor Paula Fletcher, referring to Ford’s plan.

The new $1.9 billion plan moves up the timeline for development, which is what the city asked for last September when councillors voted against Mayor Rob Ford’s bid to take over Waterfront Toronto, the city-provincial-federal agency tasked with developing the lakeshore area. The city also joined on as a partner.

The original plan for the Port Lands was contingent on making the area floodproof in case of a massive storm that would overwhelm the Don River. Accomplishing that meant moving the mouth of the river from the Keating Channel to the Toronto Harbour, an immense undertaking with a price tag of more than $600 million — a sum Waterfront Toronto didn’t have.

Instead, this time around, landscape architect Michael Van Valkenburgh has taken a novel approach to flood protection, reconfiguring the proposal so flood protection is phased in one area at a time. This also reduces the initial costs.

And it means parts of the 400-hectare Port Lands can be sold off for development, with the money used to build flood protection in another area.

“One thing that was very clear is that people wanted something started in the Port Lands, for something to come out of this exercise,” says Fletcher. “And to not have something to start with would be very sad.”

But she notes, “It doesn’t have to be all done at once,” and the proposal will be phased in over 30 years.

Currently, there’s no funding for the project. But David Kusturin, chief operating officer, says Waterfront Toronto’s business plan shows development revenues will cover a significant portion of the costs.

Other money may come through loans from the city or province. There’s also a new revenue idea: instituting area-specific development charges to offset infrastructure costs.

The agency said it consulted with developers, who have indicated they are willing to help pay for services such as water and sewer. “It makes sense for us to proceed,” Kusturin says.

The plan calls for a bus rapid transit line that will eventually be replaced with light rail. The city is currently looking at many ways to increase overall transit funding, including road tolls and gas or sales taxes. An extended transit package expected this fall will include the BRT proposal as well as the East Bayfront streetcar line along Queens Quay, explains deputy city manager John Livey.

An environmental assessment of the new proposal could be approved within the next 12 to 18 months, says Fletcher, who will push city council for the $65 million needed to create flood protection in phase one.

In that phase, the northwest corner of the Port Lands, south of Lake Shore Blvd. and west of Cherry St., will be developed at a total cost of $447 million, including $267 million in infrastructure costs. The site will be raised slightly higher.

Flood protection involves building a spillway along the Don Roadway, east of the area, to absorb excess flow in the event of flooding.

The mouth of the Don won’t be relocated until phase three of the bigger project.

The Port Lands area is almost as big as the region from Dundas St. to the lake and from Bathurst St. to Parliament St. The soil must be cleaned because it’s contaminated from years of industrial use, and because the area is largely infill, the bedrock lies 10 to 20 metres below the surface, which increases construction costs.

Planning for this project “has been arduous and very tough,” says Fletcher. “The public scrutiny is very high, as it should be. At the end we’ve got something pretty darn good.”

The new proposal will go to the executive committee in September and city council a month later.

Floods in Phnom Penh Likely to Worsen

Source: Tuesday, 07 August 2012  Justine Drennan

Cars, motorbikes and pedestrians struggle through knee-deep water last May around Phnom Penh’s Kandal market. Photograph: Heng Chivoan/Phnom Penh Post

During this year’s rainy season in Phnom Penh, new obstacles facing the city’s drainage system will probably outweigh improvements, experts said this week.

Key to that prediction is the recent completion of the scheme to fill Boeung Kak lake with sand, which they say will increase flooding, and the fact that the ongoing drainage project supported by the Japan International Cooperation Agency remains years away from completion.

Nora Lindström, advisor at urban NGO Sahmakum Teang Tnaut, which published a 2008 study on the effects of filling in Boeung Kak, said the lake can no longer hold run-off that previously drained there.

“The Boeung Kak area [where people have been given land titles] has been flooded this year already during heavy rains, as it appears drainage pipes have been blocked by the sand,” Lindström said.

She added that supposed mitigating measures taken by the developer, ruling Cambodian People’s Party Senator Senator Lao Meng Khin’s Shukaku Inc, were not “based on sound engineering”, according to the 2008 study.

Meanwhile, the new phase of JICA’s Project for Flood Protection and Drainage Improvement in Phnom Penh that begun in March is still in its early stages.

“This project is expected to finish at the end of 2015, so unfortunately, the effect of this project will be limited for this year’s flood season,” said Uchida Togo, Environment and Climate Change specialist for JICA’s Cambodia Office.

The project’s US$44.2 million new phase will involve several neighbourhoods across the city. Drainage systems installed in previous phases in the city’s northeast and southwest have already helped minimize flood damage, Uchida said.

But he stressed that the public must “try to avoid leaving the garbage outside on the street so that it would not clog the drainage system.”

National Committee for Disaster Management’s Pey Sopheap said that regarding the severity of flooding this year, “for the estimation, we cannot say anything”.

According to the municipality’s website, Phnom Penh’s district governors met on July 18 to coordinate emergency flood management.

To contact the reporter on this story: Justine Drennan at

Survival Lessons From an Ancient Failed City



Survival Lessons From an Ancient Failed City

The city of Angkor Wat, Cambodia, was a vibrant, growing metropolis in the late 17th century. Angkor was the New York, Paris or Rome of its time. At its peak from the 9th to 17th centuries AD, no one could have imagined any threat to this Khmer city-state. Yet, Angkor collapsed almost totally in the 17th century, and the reasons behind its demise offer an important lesson for today’s cities.

Angkor was built on a vast transportation network: canals acted substantially like freeways. The metropolis grew by expanding its network of canals from the central city to form a vast complex of suburban satellites. As depicted below, this was a gigantic enterprise. Ankgor grew exponentially as internal wealth and power increased. The waterways allowed goods and people to move well beyond the central core of the city.

Angkor Wat Water Suburbanization, photo by Roland Fletcher

But as Angkor continued to grow, its waterways became more fragile and vulnerable. Rain and other small but severe weather changes occurred, and the system began to crumble. My colleague Roland Fletcher, a professor of architecture at the University of Sydney in Australia, describes this process as “low density metropolitan collapse.”

Fletcher excavates cities to discover their social, physical, and economic trajectories. He and his colleagues have found a high correlation between extensive low-density suburbanization and subsequent metropolitan collapse. His thesis is that city expansion increases with wealth, which leads to, in essence, suburbanization.

Angkor expanded in a mild weather period. So, Angkor policymakers assumed this weather regime would continue forever and thus built their canals with few water catchments and earthen dams.

Today’s sprawling cities expanded in a period of mild weather too, with no anticipation that seas might rise or energy resources could be depleted. Angkor and modern cities resemble one another in that they were built to survive in only the most benign weather regimes. The roads, sewers and the like of the modern suburb are based on an assumption of mild weather and cheap energy. Recent events like Hurricane Katrina in New Orleans and subsequent Midwestern intense storms show how poorly modern infrastructure performs in extreme weather.

Elongated shallow roads and related infrastructure are as vulnerable today to destructive forces as Angkor Wat’s canals were. Fletcher explains the consequences of this process from dense city to decaying suburbs in the video below:

There may be some debate over the causes and consequences of how cities rise and fall, but there is no doubt we have similar processes at work now in America. New Orleans, Grand Forks, North Dakota, and urban South Central Florida have experienced crippling disasters in the last two decades, where part of the cities have been destroyed beyond our capacity to rebuild them.

In 2012, there were more national emergencies for tornadoes, hurricanes, and snow storms that in any other year since records have been kept. As sea levels rise and weather patterns are increasingly unpredictable, basic city settlement systems are failing. Angkor Wat was not the first or last place to go through this evolution of city boom, sprawl and bust. Beirut and other cities around the world have grown and retreated as climatic conditions changed.

And of course, we don’t have to look as far back for even more analogues. As our energy supplies dwindle, we’ve watched as radical weather imperils America’s aging infrastructure. It is too simple to suggest that we can draw direct parallels here. But it is useful to learn from the past as we try to build or rebuild for the future. It is also unwise to suggest all suburbs are bad. What policymakers have to confront is what can we do in light of this past evidence.

Two blighted houses sit vacant in the Lower Ninth Ward of New Orleans. Photo by Lee Celano/Reuters

Climate change plays a part but is not the sole culprit. New Orleans, where I spent considerable time post-Katrina as Recovery Czar, is a classic example of city sprawl. The city had almost 15,000 vacant units of housing in its core when the storm hit in 2005. City leaders had expanded the city into surrounding swamplands from 1965 to 1990, doubling the geographic size of the city. So when the storm hit, the city was expanded beyond the bulwarks of levees, leaving the entire city vulnerable to sea surges destroying much of the suburban infrastructure.

Many American cities have large suburban extensions held together by vast, over-stretched infrastructure. As Fletcher notes, the expansion of low-rise land use patterns require continued expansion of roads, water, and energy resources. This, in turn, could lead to a situation much like New Orleans, where the entire city framework is threatened when climate change alters rain, heat, and sea levels. Beijing experienced this phenomena last month with more than 30 lives lost because the expanded city could not support the volumes of flood water created by expansions of the city into surrounding natural habitat.

The lesson for American and similar land use pattern nations like Canada and Australia is to build compact, flexible settlements. One direction already underway is urban consolidation, in cities such as Miami, Indianapolis, and Louisville. Another is containment of sprawl, similar to Portland and Seattle and now Los Angeles. Finally, Denver, Phoenix, and Dallas are trying to re-knit the suburbs with the cities using light rail to generate development along corridors rather than continuous outward development. All of these approaches at this point have merit, but they may not be enough to prevent massive systems failures. So as the nation debates the need for more infrastructure spending, it would be wiser to think of a strategy to improve city cores and reinforce transport spines. Angkor Wat is a useful lesson because it shows that if we don’t take drastic action, we are all facing the grim prospect of massive regional system failures. Cities can generate suburbs; but suburbs cannot save the city.

Photo credit: Andrew L. /Shutterstock

Edward J. Blakely is honorary professor of urban policy at the United States Studies Centre at the University of Sydney. He served as the Executive Director of Recovery in New Orleans after Hurricane Katrina. He is an international urban policy theorist and practitioner. His most recent book is My Storm. All posts »