For years, experts had been warning that Houston was a hurricane disaster waiting to happen. The city is built on a massive flood plain next to the Gulf of Mexico, which routinely sends big rainstorms its way. As the city has grown into the nation’s fourth largest, developments have gone up in areas that more strictly regulated states wouldn’t allow. And with the long-term risks to Houston rising, there’s no easy or cheap fix, writes Ralph Vartabedian in the Los Angeles Times

Houston is built on what amounts to a massive flood plain, pitted against the tempestuous Gulf of Mexico and routinely hammered by the biggest rainstorms in the nation.

It is a combination of malicious climate and unforgiving geology, along with a deficit of zoning and land-use controls, that scientists and engineers say leaves the nation’s fourth most populous city vulnerable to devastating floods like the one caused this week by Hurricane Harvey.

“Houston is very flat,” said Robert Gilbert, a University of Texas at Austin civil engineer who helped investigate the flooding of New Orleans after Hurricane Katrina. “There is no way for the water to drain out.”

Indeed, the city has fewer slopes than a shower floor.

Harvey poured as much as 374 billion gallons of water within the city limits, exceeding the capacity of rivers, bayous, lakes and reservoirs. Experts said the result was predictable.

The storm was unprecedented, but the city has been deceiving itself for decades about its vulnerability to flooding, said Robert Bea, a member of the National Academy of Engineering and UC Berkeley emeritus civil engineering professor who has studied hurricane risks along the Gulf Coast.

The city’s flood system is supposed to protect the public from a 100-year storm, but Bea calls that “a 100-year lie” because it is based on a rainfall total of 13 inches in 24 hours.

“That has happened more than eight times in the last 27 years,” Bea said. “It is wrong on two counts. It isn’t accurate about the past risk and it doesn’t reflect what will happen in the next 100 years.”

In an average year, Houston gets 50 inches of rain — as much as Harvey will deliver to some parts of the city.

The muddy rivers — notably the San Jacinto and the Buffalo Bayou — that meander through Houston struggle to carry much water.

Dams along the rivers were built mainly for water storage, not flood control. Because Texas is so flat, the dams can’t hold much water, unlike western dams that are built in deep gorges.

Lake Conroe, a reservoir 43 miles north of the city, is one example. Completed in 1973, it has a capacity of 430,000 acre-feet, about 12% of Oroville Dam in California.

The San Jacinto River Authority, which manages water supplies, knew that Harvey was probably headed its way. But a spokeswoman, Rhonda Trow, said the authority chose not to release water from Lake Conroe in advance because the amount it held wouldn’t have made a difference and could have caused flooding even before the storm hit.

But by Monday, the authority had no choice but to open the flood gates to send 79,141 cubic feet of water to flooded Houston every second.

The situation was similar on two dams on the Buffalo Bayou controlled by the Army Corps of Engineers up river from the Houston Ship Channel.

The long-term risks facing Houston are growing, owing to warming water temperatures in the Gulf of Mexico, which will fuel more powerful hurricanes by increasing the moisture they carry.

Harvey caused a surge in the Gulf of Mexico that raised its level by as much as 15 feet along the Texas coast, Bea estimated. That meant that for some period of time, rivers were not flowing normally, leaving inland areas less than 15 feet above sea level with little drainage.

In Katrina, the level of the gulf surged by 28 feet, the largest ever recorded along the Gulf Coast, sending water pouring over levees and canal walls. But far less rain fell in that storm than in Harvey.

Beyond the climate change, Houston faces other growing risks for flooding.

Shuhab Khan, a geologist at the University of Houston, has documented that some areas of Houston are sinking at up to 2.2 inches per year, a rapid rate in geological terms.

While some of the subsidence is caused by natural movements of salt deposits, Khan said that most is the result of pumping oil and water from under the city.

So far, it appears some of the hardest-hit flooded areas, such as the Jersey Village nieghborhood, are also the ones affected by subsidence, he said.

In the 1930s, a new residential subdivision was built in the Brownwood neighborhood, which at the time was 10 feet above sea level. Forty years later, it was less than 2 feet above sea level, a subsidence blamed on ground water pumping along the Houston Ship Channel. The neighborhood was destroyed in Hurricane Alicia in 1983 and is now the Baytown Nature Center.

Another long-term problem is the city’s rampant growth and urbanization. The city has 2.2 million residents and the metropolitan area has 6.5 million, all living in a state that eschews much of the zoning and land-use controls that help keep construction away from flood zones in states with more regulations.

“It is naturally prone to flooding,” said Don Riley, the former chief of the Army Corps of Engineers civil works division. “People have built in this massive flood plain. They have to understand that.”

The Corps and local officials have discussed ways to avert even greater risks by improving zoning, reducing the amount pavement to allow better drainage into the soil, building retention ponds in new housing developments and constructing new storm barriers. But when the Corps has tried to encourage land-use controls, the local reaction by politicians and developers has often been swift and furious, Riley said.

“The problem is not decreasing, whatever the future of the weather is,” he said. “It will worsen in the sense that there will be more population. You have to be smart about where you put development.”

The future defense of Houston is likely to be expensive, experts said. The Corps spent $14.2 billion to improve flood control in New Orleans after Katrina, which was aimed at building up levees and flood walls. But just this month, the city was again flooded when its decrepit pumping system was overwhelmed by rainfall.

In the aftermath of Katrina, the American Society of Civil Engineers said that New Orleans’ flood control was a system in name only.

Bea said that reflects the reality of Houston as well.

He estimated that it could cost hundreds of billions of dollars to build a system that would prevent future flooding, involving land-use restrictions, new flood barriers and other measures similar to those in the Netherlands. The Dutch system attempts to defend Amsterdam and Rotterdam from a 10,000-year storm event.

Exactly what Houston could do is far from certain. Gilbert, the University of Texas expert, said any big measures would take a lot of study. Chicago, for example, has massive tunnels hundreds of feet underground that can store 21 billions of gallons storm water and prevent sewage contamination of Lake Michigan, he noted.

“Houston is excessively developed,” he said. “It has 6 million people with lots of concrete and lots of people in harm’s way.”

The 10th meeting of the Advisory Board of the Climate Technology Centre and Network (CTCN) commenced on Tuesday, August 29, 2017 in Copenhagen, Denmark, with the coming 23rd Session of the Conference of the Parties (COP23) to the United Nations Framework Convention on Climate Change (UNFCCC) high on the agenda. The global climate summit will hold from November 6 to 17, 2017 in Bonn, Germany.

The CTCN is accountable to the Conference of the Parties (COP) of the UNFCCC through the CTCN Advisory Board. The Advisory Board meets twice per year and provides direction on the CTCN’s fulfillment of the COP’s guidance.

Consequently, the meeting, scheduled to end on Thursday, August 31, is addressing the Bonn climate change conference (SB 46), and preparations for COP23.

Board members are also reviewing communications and outreach plans for COP23.

On the UNFCCC’s Technology Mechanism, board members are addressing issues bordering RD&D activities, Technology Framework submission to SBSTA (Subsidiary Body of Scientific and Technological Advice) 47, Submission to the Paris Committee on Capacity Building, and Independent Review of the CTCN by the UNFCCC secretariat.

The SBSTA is one of two permanent subsidiary bodies to the Convention established by the COP/CMP. It supports the work of the COP, the CMP (Conference of the Parties serving as the meeting of the Parties to the Kyoto Protocol) and the CMA (Conference of the Parties serving as the meeting of the Parties to the Paris Agreement) through the provision of timely information and advice on scientific and technological matters as they relate to the Convention, its Kyoto Protocol and the Paris Agreement.

On the CTCN operations moving forward, participants will be discussing: Technical assistance requests and process; Capacity building, Network and stakeholder/private sector engagement; Knowledge Management System and technology content; M&E – Framework for measuring and evaluating CTCN-wide impact; Gender; and Plans for COP23.

An information session, themed “CTCN Experiences: Perspectives of NDEs and Technical Assistance Providers”, holds on August 29 and August 30.

The meeting is holding at the UN City, Marmorvej, in Copenhagen.

Erstwhile Director, Department of Climate, Federal Ministry of Environment in Nigeria, Dr Samuel Adejuwon, is a member of the CTCN Advisory Board.

World leaders, water experts, development professionals, policy-makers, and one astronaut, have gathered in Stockholm, the Swedish capital city, for a week-long meeting focused on finding ways to better use, and reuse, the world’s increasingly scarce fresh water.

The term “water scarcity” is becoming increasingly common. As more countries, and cities, experience the effects of high population pressure and less available freshwater, the interest among policy-makers, businesses, and citizens grows. The realisation is there. We need to become more efficient water users. We need to make some drastic changes.

“World Water Week is a key meeting place for the water and development community; it is here that we come together and make sure that the very best ideas are brought forward,” said SIWI’s Executive Director, Torgny Holmgren.

World Water Week is said to be the world’s biggest global annual meeting focusing on water and development. It is organised by the Stockholm International Water Institute (SIWI). The Week draws over 3,000 participants from nearly 130 countries, who come to Stockholm to learn about new research results, share experiences, discuss progress in the implementation of the Global Goals, and together try to find new ways to meet the world’s growing water challenges.

The President of the United Nations General Assembly, Peter Thomson, called the world’s climate and water resources the “fundament of our existence”, and said that “Without proper stewardship of that fundament the 2030 sustainable development agenda obviously goes nowhere. Because without the fundament we can’t exist.”

“Together with the Paris Climate Agreement, implementation of the 17 Sustainable Development Goals represents the best chance our species has to achieve a sustainable way of life on Planet Earth before it is too late,” he added.

Sweden’s Minister for Environment, Karolina Skog, said: “Sustainable and efficient management of our water and wastewater (…) has a profound effect on all aspects of human life; economic growth, sustainable development, sustainable city planning, circular thinking in industry and in production, energy saving, good quality of our water and, last but not least, it is crucial for health and for a sustainable environment.”

Astronaut and Member of Sweden’s Royal Academy of Science, Christer Fuglesang, described the intricate water reuse systems that are necessary during space missions, enabling food to be grown on board, and ensuring a drinking water supply – both helping to inform research, and optimise methods for increased water use efficiency on earth.

Another central aspect of efficient water use, is to use less. In his welcoming speech Holmgren pointed out that it will be challenging but necessary to change large-scale water consumption patterns: “The Week’s theme, Water and waste: Reduce and reuse, really touches the very core of our daily lives. To reduce, some drastic changes will be necessary – especially by the main water users, including industries, energy producers and the agriculture sector.”

He added that changes are also needed in how we think about reuse of water: “I think that it is very important to try and change the mind-set around waste. Rather than presenting us with a problem, we can view waste as an asset also becoming a business opportunity.”

Stephen McCaffrey, 2017 Stockholm Water Prize Laureate and a Professor in water law, spoke of the need for water cooperation and water diplomacy. He told participants that although the ingredients for potential water conflicts exist, such as higher population pressure, climate change, and much of the world’s fresh water being shared by two or more countries, studies show that water sharing is much more likely to lead to cooperation than conflict.

The death toll from Tropical Storm Harvey is expected to rise as Houston and a wide swath of Texas face record rains and catastrophic flooding.

With deadly power, Tropical Storm Harvey has inundated Houston and southeastern Texas, bringing up to 2 feet of rain in 24 hours in the nation’s fourth largest city and triggering flooding that the National Weather Service called “catastrophic” and “unprecedented.”

At least five people were reported to have died, and authorities expect the death toll to rise. More than a dozen injuries have been blamed on the storm, which made landfall on Friday night as a Category 4 hurricane, the most powerful to hit the United States in a decade. Its winds have slowed to tropical-storm force.

Meanwhile, 911 operators fielded 56,000 calls in less than 24 hours, pleas for help went out over social media, thousands of rescues took place, and some residents made desperate treks across Houston’s sprawling freeways. The White House says President Trump will travel to Texas on Tuesday.

With record floodwaters devastating much of southeast Texas, more than 450,000 people are likely to seek federal aid in recovering from Harvey, the storm that has battered the Gulf Coast for days, Brock Long, the director of the Federal Emergency Management Agency, said on Monday. The agency has estimated that about 30,000 people will seek emergency shelter, and that federal aid will be needed for years.

The Houston region now looks like an inland sea dotted by islands, with floodwaters inundating roads, vehicles, and even bridges and buildings. Thousands of people have been rescued from flooded homes and cars and many more are stuck in homes that remained above water but are cut off.

More than 30 inches of rain has fallen on parts of the Houston area since Thursday, the National Weather Service reported on Monday, causing catastrophic flooding that officials have called the worst in the state’s history. Torrential rains will continue through Friday, with an additional 15 to 25 inches pummeling the region, the Weather Service predicted.

Harvey turned back out to sea on Monday morning, with the centre of the storm reaching the Gulf of Mexico between Corpus Christi and Houston, the National Hurricane Centre reported. It was expected to move slowly to the southeast on Monday, before churning to the northeast, along the Gulf coast.