Tag Archives: flood insurance

Our Flood Insurance System is Broken. Here’s How We Fix It.

Matthew Nielsen, senior director, governmental and regulatory affairs, RMS

Daniel Stander, managing director, RMS

This blog was first published in The Hill

Breezy Point, N.Y., Oct. 31, 2012 – Street scene after Hurricane Sandy. Source: FEMA

Katrina. Sandy. Matthew. We tend to remember the big-name storms that take over the news cycle for weeks, offering up poignant images of rescued families.

Yet many of us barely notice losses racked up annually from flooding events all over the U.S.: flash floods in the Midwest and Northeast, torrential rains in bone-dry Houston, dam spillways exploding in formerly drought-stricken California.

Continue reading

The Impact of Insurance on Claiming

The term “observer effect” in physics refers to how the act of making an observation changes the state of the system. To measure the pressure in a tire you have to let out some air. Measure the spin of an electron and it will change its state.

There is something similar about the “insurer effect” in catastrophe loss. If insurance is in place, the loss will be higher than if there is no insurer. We see this effect in many areas of insurance, but now the “insurer effect” factor is becoming an increasing contributor to disaster losses. In the U.S., trends in claiming behavior are having a bigger impact on catastrophe insurance losses than climate change.

Continue reading

Can Flood Walls Reduce Resilience?

In early December 2015 Storm Desmond hit, bringing an “atmospheric river” to the northwest of England with its headwaters snaking back to the Caribbean. It broke the U.K.’s 24 hour rainfall record, with 341.1mm of rain recorded in Cumbria.

Just three weeks later, while a great anticyclone remained locked in place over central Europe and the atmospheric flows had only shifted south by 150km, Storm Eva arrived. The English counties of Lancashire and Yorkshire were drenched during December 26th, and the media was once more overwhelmed with flood scenes—streets of Victorian-era houses inundated by 30-40cm of slow-moving water.

Journalists soon turned their attention to the failure of flood protections in the affected regions. In one interview in Carlisle, a beleaguered Environment Agency representative commended their defenses for not having failed—even when they had been overtopped. If the defenses had failed, maybe the water would not have ponded for so long.

 The call for “resilience”?

The call has gone out worldwide for improved “resilience” against disasters. As outlined by the UN Secretary General’s Climate Resilience Initiative, resilience is defined as the ability to “Anticipate, Absorb and Reshape” or “A2R”.

How did the U.K.’s flood defenses match up to these criteria in December? Well, as for the two “A”s in A2R, the residents of Carlisle did not anticipate any danger, thanks to the £38 million spent on flood defenses since the last time Carlisle had a “1 in 200 year” flood in January 2005 (which hit 1,900 properties). And the only thing the houses of Carlisle were absorbing on the first weekend in December was the flood water seeping deep into their plaster, electricals, and furnishings. As for “reshaping”, beyond the political recriminations, now is the time for some serious thinking about what constitutes resilience in the face of floods.

A flood wall is not the same as resilience. Resilience is about the capacity to recover quickly from difficulties, to bounce back from adversity. Organizations such as the UK’s Environment Agency may be good at building flood defenses, but not so proficient at cultivating resilience.

A flood wall can certainly be part of a culture of resilience—but only when accompanied by regular evacuation drills, a flood warning system, and recognition that despite the flood wall, people still live in a flood zone. Because flood walls effectively remove the lesser more frequent floods, the small risk reminders go away.

A growing reliance on the protection provided by flood walls may even cause people to stop believing that they live in a flood plain at all, and think that the risk has gone to zero, whether this is in New Orleans, Central London or Carlisle.

Even when protected by a flood wall, residents of river flood plains should be incentivized, through grants and reduced insurance rates, to make their houses resistant to water: tiling walls and floors and raising electrical fittings. They should have plans in place—such as being ready to carry their furniture to an upper floor in the event of an alert—as one day, in all probability, their houses will flood.

Given the U.K.’s recent experience we should be asking are people becoming more resilient about their flood risks? It sometimes seems that the more we build flood walls, the less resilient we become.

Are (Re)insurers Really Able To Plan For That Rainy Day?

Many (re)insurers may be taken aback by the level of claims arising from floods in the French Riviera on October 3, 2015. The reason? A large proportion of the affected homes and businesses they insure in the area are nowhere near a river or floodplain, so many models failed to identify the possibility of their inundation by rainfall and flash floods.

Effective flood modeling must begin with precipitation (rain/snowfall), since river-gauge-based modeling of inland flood risk lacks the ability to cope with extreme peaks of precipitation intensity. Further, a credible flood model must incorporate risk factors as well as the hazard: the nature of the ground, such as its saturation level due to antecedent conditions, and the extent of flood defenses. Failing to provide such critical factor can cause risk to be dramatically miscalculated.

A not so sunny Côte d’Azur

This was clearly apparent to the RMS event reconnaissance team who visited the affected areas of southern France immediately after the floods.

“High-water marks for fluvial flooding from the rivers Brague and Riou de l’Argentiere were at levels over two meters, but flash floodwaters reached heights in excess of one meter in areas well away from the rivers and their floodplains,” reported the team.

This caused significant damage to many more ground-floor properties than would have been expected, including structural damage to foundations and scouring caused by fast-floating debris. Damage to vehicles parked in underground carparks was extensive, as many filled with rainwater. Vehicles struck by more than 0.5 meters of water were written off, all as a result of an event that was not modeled by many insurers.

The Nice floods show clearly how European flood modeling must be taken to a new level. It is essential that modelers capture the entire temporal precipitation process that leads to floods. Antecedent conditions—primarily the capacity of the soil to absorb water must be considered, since a little additional rainfall may trigger saturation, causing “saturation excess overland flow” (or runoff). This in turn can lead to losses such as those assessed by our event reconnaissance team in Nice.

Our modeling team believes that to achieve this new level of understanding, models must be based on continuous hydrological simulations, with a fine time-step discretization; the models must simulate the intensity of rainfall over time and place, at a high level of granularity. We’ve been able to see that models that are not based on continuous precipitation modeling could miss up to 50% of losses that would occur off flood plains, leading to serious underestimation of technical pricing for primary and reinsurance contracts.

What’s in a model?

When building a flood model, starting from precipitation is fundamental to the reproduction, and therefore the modeling, of realistic spatial correlation patterns between river basins, cities, and other areas of concentrated risks, which are driven by positive relationships between precipitation fields. Such modeling of rainfall may also identify the potential for damage from fluvial events.

But credible defenses must also be included in the model. The small, poorly defended river Brague burst its banks due to rainfall, demolishing small structures in the town of Biot. Only a rainfall-based model that considers established defenses can capture this type of damage.

Simulated precipitation forms the foundation of RMS inland flood models, which enables representation of both fluvial and pluvial flood risk. Since flood losses are often driven by events outside major river flood plains, such an approach, coupled with an advanced defense model, is the only way to garner a satisfactory view of risk. Visits by our event reconnaissance teams further allow RMS to integrate the latest flood data into models, for example as point validation for hazard and vulnerability.

Sluggish growth in European insurance markets presents a challenge for many (re)insurers. Broad underwriting of flood risk presents an opportunity, but demands appropriate modeling solutions. RMS flood products provide just that, by ensuring that the potential for significant loss is well understood, and managed appropriately.

South Carolina Floods: The Science Behind the Event and What It Means for the Industry

South Carolina recently experienced one of the most widespread and intense multi-day rain events in the history of the Southeast, leaving the industry with plenty to ponder.

Parts of the state received upwards of 27 inches (686 mm) of rain in just a four day period, breaking many all-time records, particularly near Charleston and Columbia (Figure 1). According to the National Oceanic and Atmospheric Administration, rainfall totals surpassed those for a 1000-year return period event (15-20 inches (381-508 cm)) for parts of the region. As a reminder, a 1000-year return period means there is a 1 in 1000 chance (0.1%) of this type of event occurring in any year, as opposed to once every thousand years.


Figure 1: Preliminary radar-derived rainfall totals (inches), September 29-October 4. Source: National Weather Service Capital Hill Weather Gang.

The meteorology behind the event

As Hurricane Joaquin tracked north through the Atlantic, remaining well offshore, a separate non-tropical low pressure system positioned itself over the Southeast U.S. and essentially remained there for several days. A ridge of high pressure to the north acted to initiate strong onshore windflow and helped keep the low-pressure system in place. During this time, it drew in a continuous plume of tropical moisture from the tropical Atlantic Ocean, causing a conveyor belt of torrential rains and flooding throughout the state, from the coast to the southern Appalachians.

Given the fact that Joaquin was in the area, the system funneled moist outflow from it as well, enhancing the onshore moisture profile and compounding its effects. It also didn’t help that the region had experienced significant rainfall just a few days prior, creating near-saturated soil conditions, and thus, minimal absorption options for the impending rains.

It’s important to note that this rain event would have taken place regardless of Hurricane Joaquin. The storm simply amplified the amount of moisture being pushed onshore, as well as the corresponding impacts. For a more detailed breakdown of the event, please check out this Washington Post article.

Notable impacts and what it means for the industry

Given the scope and magnitude of the impacts thus far, it will likely be one of the most damaging U.S. natural catastrophes of 2015. Ultimately, this could be one of the most significant inland flooding events in recent U.S. history.

This event will undoubtedly trigger residential and commercial flood policies throughout the state. However, South Carolina has just 200,000 National Flood Insurance Program (NFIP) policies in place, most of which are concentrated along the coast, meaning that much of the residential losses are unlikely to be covered by insurance.


Figure 2: Aerial footage of damage from South Carolina floods. Source: NPR, SCETV.

Where do we go from here?

Similar to how Tropical Storm Bill reiterated the importance of capturing risk from tropical cyclone-induced rainfall, there is a lot to take away from the South Carolina floods.

First, this event underscores the need to capture interactions between non-tropical and tropical systems when determining the frequency, severity, and correlation of extreme precipitation events. This  combined with high resolution terrain data, high resolution rainfall runoff models, and sufficient model runtimes will optimize the accuracy and quality of both coastal and inland flood solutions.

Next, nearly 20 dams have been breached or failed thus far, stressing the importance of developing both defended and undefended views of inland flood risk. Understanding where and to what extent a flood-retention system, such as a dam or levee, might fail is just as imperative as knowing the likelihood of it remaining intact. It also highlights the need to monitor antecedent conditions in order to properly assess the full risk profile of a potential flood event.

The high economic-to-insured loss ratio that is likely to result from this event only serves to stress the need for more involvement by private (re)insurers in the flood insurance market. NFIP reform combined with the availability of more advanced flood analytics may help bridge that gap, but only time will tell.

Lastly, although individual events cannot be directly attributed to climate change, these floods will certainly fuel discussions about the role it has in shaping similar catastrophic occurrences. Did climate change amplify the effects of the flooding? If so, to what extent? Will tail flood events become more frequent and/or more intense in the future due to a rising sea levels, warming sea surface temperatures, and a more rapid hydrologic cycle? How will flood risk evolve with coastal population growth and the development of more water impermeable surfaces?

This event may leave the industry with more questions than answers, but one stands out above the rest: Are you asking the right questions to keep your head above water?