Flood Barrier USA

2020 Hurricane Season Poised to Break Records

Author: Donna Conneely

At the beginning of June, the 2020 hurricane season was already looking busy, with at least nine major ‘named’ storms predicted by the National Oceanographic and Atmospheric Agency (NOAA). As of the middle of August, these nine named storms have already come and gone, and the tenth, Josephine, is forming on the horizon. With a full three and half months left in the season, we have already exceeded the predicted number of storms for the entire season. This is an indication that we may be in for a record-smashing year.

According to records kept by NOAA, most years will suffer an average of 10-12 named storms, of which an average of 6 become hurricanes. Of those 6 hurricanes, 2-3 will become major hurricanes- meaning Category 3 or higher. In preparation for the season, NOAA prepares and publishes the names for that year’s expected storms, so that weather professionals can be prepared and coordinated across the affected regions.

A visible NOAA GOES-16 satellite image of Hurricane Isaias as it approached the U.S. East Coast at 7:46 p.m. ET, August 3, 2020. (NOAA)

The names for the storms come from a list that is maintained by the World Meteorological Organization (WMO), and this list is strictly proscribed and inflexible. The names are assigned in order, alphabetically, with male and female names alternating. There are six lists of names, which are used in rotation, and after six years the cycle of names begins again. There are no names assigned to the letters Q,U,X,Y, and Z, so there are 21 names prepared at the start of each hurricane season. Very, very rarely is this list of 21 storm names inadequate to cover a year’s worth of named storms. One such year was 2005.

The year 2005 was a record-breaker in many ways. That year, a full 28 storms were strong enough to be assigned a name from the WMO, among them the infamous Hurricane Katrina. Storms like Katrina cause a rare alteration to the strict list of storm names, because these monster storms are so deadly and costly that using the name again would be painful to its victims, even six years later. In this rare case, the name of the notorious storm is permanently retired.

The other reason that the year 2005 was a record-breaker is that with 28 named storms, it used up all the names available for the year, and then some. In the event of this very infrequent circumstance, there is an ‘overflow list’ of other names derived from the Greek alphabet. When we hear of storms named Alpha or Beta, we know that this is not a normal year!

For this current year of 2020, with a global pandemic causing death and disruption across the planet, there are as many as 24 named storms considered likely. As the hurricane season extends from June 1 through November 30, we are currently only 1/3 of the way through the season, with ten storms already named! This means that we may have Hurricane Gamma on our hands by the end of the season. Any year in which the NOAA has to dip into the ‘Greek names’ is likely to be a bad year for anyone living or owning property in the hurricane zone- and we can only hope that another storm like Katrina will not appear in this already challenging and deadly year.

September 1st, 2020  |  Posted in Flood Protection  |  No Comments »

Flooding Disaster in Michigan

Author: Donna Conneely

In late May, the town of Midland, Michigan suffered severe inundation that has been described as a “500-year flooding event”. Although there was no loss of life, the flooding was so extreme and damaging that it dwarfed all other flooding events in living memory. At least 10,000 residents were displaced, and this displacement was complicated by the global pandemic that has swept through the United States. As evacuees arrived at shelters, each person was screened for symptoms of COVID-19, and was then escorted to a spot that was purposely separated from other evacuees by as much space as possible. But as more and more people trickled into the shelters, that spacing became very difficult to maintain. The challenges of coping with any natural disaster is hard enough, but to couple those challenges with an extraordinary public health crisis makes the effort truly Herculean in scope and ramification.

These natural-color images show flooding across Midland County as observed by the Operational Land Imager (OLI) on Landsat 8. The pair shows the Tittabawassee River on May 20, 2020 (right), compared to June 3, 2019 (left). NASA Earth Observatory images by Joshua Stevens, using Landsat data from the U.S. Geological Survey.

The flooding in Midland has been called ‘a nightmare situation’ that developed after days of heavy rainfall. All this precipitation poured into the lakes at Edenville and Sanford- and the lakes were quickly filled to the brim. Unfortunately, the dam at Edenville had been known as a problem structure for some time; in fact, its license had been revoked by federal inspectors in 2018. The stated reason for the forfeiture of the license was simple: the dam was deemed unlikely to withstand a significant flood. Fast forward two years, and that ‘significant flood’ materialized- at the worst possible moment.

In addition to the hazards posed by the global pandemic, the state of Michigan- as well as much of the rest of the United States- has been embroiled in momentous and widespread civil disturbances and demonstrations. Close to 20% of the US work force is furloughed or otherwise unemployed due to the global COVID-19 pandemic. A large number of people who have been unable to make their rent or mortgage payments are hovering on the brink of homelessness. Emergency services, National Guard, local and federal law enforcement, food banks, shelters, and health care services were already overwhelmed even before the rain began to fall. And then, the rain began to fall- relentlessly.

The run-off from the heavy storms filled Lake Wixom, which was held back by the Edenville Dam. This earthen embankment dam was built in 1924 by a former circus owner named Frank Wixom, who was presumably not an expert engineer. To his credit, Wixom’s earthen dam contained the lake for 94 years, even holding up for a couple of years after it was inspected and deemed unlikely to withstand a major flood. Two years after that inspection, however, Frank Wixom’s old dam finally collapsed.

Much had changed in the years since 1924, including a lot of development along the river as well as the construction of a second dam at Sanford, about ten miles downstream. When the Edenville dam collapsed, a powerful wall of water hurtled towards the next dam, and quickly overwhelmed it. Now two consecutive dams had failed! At this point, the combined volumes of the heavy rainfall, the contents of Wixom Lake, and the contents of Sanford Lake all barreled towards the small city of Midland.

Luckily, there had been engineers monitoring the state of the Edenville dam during the storms. Having failed the inspection, the dam was not to be trusted. At the point that it became likely that the Edenville dam would fail, warnings were issued and the residents of Midland were evacuated. Shortly after the final evacuations were complete, Edenville Dam washed away, with Sanford Dam falling soon after. The town of Midland was soon under nine feet of water.

Now, in the places where Lake Wixom and Lake Sanford used to delight boaters and the homeowners who lived on the banks, gigantic, reeking mud flats stretch to the horizon. Erosion is a huge concern to property owners, as these lakeside structures are now in danger of sliding into the muck. Litigations have already commenced, but restitution and insurance money is a long way off. The community is coming together as much as possible to assist those affected by the flooding, but that group includes almost all of Midland. One thing is certain: the amount of money needed to restore Midland and the two destroyed dams- to say nothing of the loss of hydro power the dams had been producing- is far greater than the amount of investment it would have taken to prevent this disaster.

July 20th, 2020  |  Posted in Flood Protection  |  No Comments »