Tropical Storm Isaias Flooding

Thank you to all the first responders on-duty as Tropical Storm Isaias has been rocking the East Coast today.  Special shout out to the Southeastern PA first responders in our neck of the woods.  Take a look at the graph below from the National Weather Service Advanced Hydrologic Prediction Service.

chestercreek

The graph shows that the minor flood stage for the Chester Creek near Chester, PA starts at 8 feet, and the height today reached into the major flood stage range at 17.1 feet.  It also shows how quickly the water is going to recede over the next 24 hours.  Remember, as the water recedes, the threat of differential pressures developing increases.

Differential pressure is caused by two bodies of water equalizing (i.e., flood water entering a storm drain).  This differential pressure can develop thousands of pounds of force and pull first responders under water.  Read more about this topic in one our earlier blog posts – Lessons Learned from a Water Rescue LODD.

We offer Flood Rescue Awareness (3 hours) and Flood Rescue Skills Development (12 hours) classes.  Contact us today to set up a class for your agency.

Stay safe!

Bill Elder
Owner / Lead Instructor
Elder Technical Rescue Services, LLC

Lessons Learned from a Water Rescue LODD

Five years ago, on May 23, 2015, a fire captain was killed, and another firefighter injured when they were pulled into a storm drain after evacuating a flooded neighborhood.  You can read the full NIOSH LODD Report here.  We will be discussing some of the key points from the report in this blog post.

storm drainSource: NIOSH

What Happened

Heavy rain and thunderstorms caused rapidly rising flood water to trap families in their homes.  Firefighters responded after 2200 hours, and over the course of an hour they rescued 10 civilians including six children from the residences.  The captain was walking back around the neighborhood to report to the incident command post when he stepped into an unmarked catch basin for a storm drain.  During the rescue effort of the captain, another firefighter was pulled into storm drain but was ejected 276 feet away at the end of the drain.  Unfortunately, the captain drowned in the storm drain.

Key Recommendations

First responders must be trained to the appropriate level in water rescue search and rescue operations.  Remember, the NFPA standards identify several different disciplines related to water rescue.  Flood rescue incidents present many dangerous conditions that are not always necessarily present in natural water ways.

One of the dangerous hazards present during flood rescue incidents is differential pressure.  Differential pressure is caused by two bodies of water equalizing (i.e., flood water entering a storm drain).  This differential pressure can develop thousands of pounds of force and must be avoided by first responders operating at flood incidents.  One way to avoid them is to identify the hazard prior to the flooding incident.  If your authority having jurisdiction has performed a thorough hazard analysis and risk assessment, then you may already have some of this information available to you.

Lastly, remember to wear the appropriate PPE at flood rescue incidents.  Dry suits, personal flotation devices (PFDs), and appropriate water rescue helmets, gloves and footwear are incredibly important.  Wearing the correct PPE will give you the best opportunity to survive in this environment and will protect you from hazardous materials contamination that is present in flood water.

Bill Elder
Owner / Lead Instructor
Elder Technical Rescue Services, LLC

Mention this blog post when scheduling our Flood Rescue Awareness (3 hours) or Flood Rescue Skills Development (12 hours) classes and receive a 10% discount.  Contact us to set up a class for your agency.

Anniversary of a Water Rescue Near Miss

Thirteen years ago on April 17, 2007, two fire fighters were seriously injured while conducting water rescue training.  The near miss occurred when they were practicing a two-boat tether rescue technique downstream of a low-head dam.  Both boats being used in the evolution eventually crossed the boil line of the hydraulic created by the low-head dam, causing four fire fighters to become victims with two of them suffering serious injuries.  For more details about this incident, read this NIOSH Report.

nioshlowheaddam
Photo of Low-Head Dam.  Source: NIOSH

What is a low-head dam and a hydraulic?

Low-head dams are walls that span a river from one side to another that restrict the flow of water downstream.  This causes a buildup of water upstream of the dam which can be used for recreational purposes.  The problem with low-head dams, is that as the water flows over the top of the dam a dangerous phenomenon known as a hydraulic is created.  Hydraulics are dangerous recirculating water that is highly aerated (in other words, has a lot of air in it).  This recirculating water pulls in unsuspecting people and objects.  Hydraulics can also be created by naturally occurring drops in rivers.

What is the two-boat tether technique and boil line?

The preferred method of performing a rescue of someone trapped in a hydraulic is from the shore using some type of reaching device or throw bag.  A more advanced evolution utilizes two rescue boats tethered to each other.  The primary or lead boat approaches the boil line from downstream while tethered to the secondary boat behind it.  Once close enough, the primary boat can use a reach device or throw bag to perform the rescue from their boat.  The secondary boat prevents the primary boat from being pulled into the hydraulic.

The boil line is the point you do not want to cross.  The boil line is where the highly aerated recirculating water starts.  Once passed the boil line, it is very difficult to escape the hydraulic.  The recirculating water constantly pulls you back under the water, and the aerated water makes your personal flotation device highly ineffective.  All of these factors together are why a lot of people call low-head dams “drowning machines.”

How many people have been killed by low-head dams?

Brigham Young University has done in-depth research on the dangers of low-head dams and maintains a database of reported fatalities.  According to their data, there have been 555 fatalities since 1952.  Unfortunately, several first responders have also been killed by low-head dams.  Two of them, Captain Stanley Balsis and Firefighter Michael Whalen, are forever memorialized by their fire department in Elgin, IL.

elginmemorialCaptain Balsis and FF Whalen Memorial.  Source: Elgin Fire Department, Elgin, Illinois Facebook Page

Bill Elder
Owner / Lead Instructor
Elder Technical Rescue Services, LLC

Mention this blog post when contacting us to set up a water rescue class for your agency and receive a 10% discount on the cost of the class!

Turning a Family Outing into a Training Opportunity

The other day I took a drive with the family to get out of the house and get some fresh air.  We traveled out to a site along the Schuylkill River in Berks County.  While enjoying the Spring weather, I took the opportunity to observe the river.  As rescue professionals, we should take every chance we get to refresh our knowledge and skills.  Watch the video below and see what different features you can identify in the moving water.


Upstream V

Upstream V’s are visual indicators that an obstruction is hiding just beneath the surface of the water.  If you find yourself in the water and are using the defensive swimming position, you will want to change your ferry angle to avoid hitting these obstructions.  There are numerous Upstream V’s at the top of this video.

Downstream V

In contrast to Upstream V’s, the Downstream V is a relatively clear path of travel.  Typically situated between two obstructions or shallower water, the Downstream V is the path you typically want to ferry towards when navigating swift water in the defensive swimming position.  There is a large Downstream V in the center of this video.

Eddy

An eddy forms behind an object in the water.  As the water moves around the object, the water must back fill the space behind the object.  That back filling results in a relatively save space that a rescuer can swim towards.  Once in the eddy, the rescuer can rest and take a moment to figure out his/her next move in the water.  The rock at the bottom of this video is an example of natural eddy.  It could also be man-made objects in the urban environment.

IMG_3371

Bill Elder
Owner / Lead Instructor
Elder Technical Rescue Services, LLC

Mention this blog post when contacting us to set up a water rescue class for your agency and receive a 10% discount on the cost of the class!