590 likes | 1.08k Vues
Water Rescue Awareness. King County in 2007 26 people drowned Most occurred in June and July- almost 30% of them in June. WA State in 2006 123 unintentional drowning deaths. Drowning is the second leading cause of unintentional death for Children ages 17 and younger. Some quick statistics.
E N D
King County in 2007 26 people drowned Most occurred in June and July- almost 30% of them in June. WA State in 2006 123 unintentional drowning deaths. Drowning is the second leading cause of unintentional death for Children ages 17 and younger. Some quick statistics
continued • Costs: One drowning death can be associated with up to $3 million in total costs, according to the National Safety Council.
Basic characteristics of moving water • Powerful • Relentless • Predictable
Learn to respect the forces associated with moving water. Before Big Thompson Flood Colorado, July 31, 1976 After
Laminar flow • Layers of moving water which are slower on the bottom and along the banks (due to increased friction) • Moving water is faster toward the center, midstream and on the outside of bends
Fastest Fast Slow Slowest Straight Section Fastest Fast Slow Slowest Outside Bend Laminar flow Water layers slow near the bottom and along banks due to friction
Helical flow • A circular flow of water along the bank forcing water to midstream • Phenomenon caused by friction between current and debris and material on the bank
Helical Flow Helical & Laminar flow Laminar Flow
Water dynamics Water is fastest…at the surface and midstream. Water slows down…along banks and bottom. Water is faster…at the outside of bends and slower on the inside of bends. Water slows down and deepens…in front of dams and other obstructions.
Surface Velocity Time for float to travel 100 feet Throw a floating object (e.g. stick) in the water and record the time it takes to travel 100 feet Velocity: measured in feet per second
Force of moving waterRule of thumb... Water Velocity x 2 = Water Force x 4 (double the velocity = quadruple the force)
Forces exerted by moving water... The force exerted on an object in water is proportional to the surface area that is exposed to the force. Double velocity, quadruple the force River Rescue, Ohio Department of Natural Resources, 1980
Classifications of water • Are in reference to that particular body of water based on normal flows and are not compared to other water systems • Are used in relation to describe the conditions for recreational use of that particular body of water • Only apply when that body of water is within its banks
Categories of swiftwater Few obstructions, very small waves Easy rapids up to 3 feet wide, obvious clear channels High irregular waves, narrow channels, requires scouting Difficult long rapids, turbulent water requires scouting, rescue is difficult Violent long rapids, scouting is mandatory, extremely dangerous rescue Almost impossible to navigate, rescue is almost impossible • Class I • Class II • Class III • Class IV • Class V • Class VI
Rivers in flood • Most rivers have a normal water level or range of normal levels of flow depending on dry spells, recent storms or spring run off but the river flow stays within its banks and is relatively predictable. • Floods, however, are outside of the usual range of river conditions, because in flood, a river overtops its banks, begins to flow through the flood plain and in the process becomes less predictable and more dangerous.
Rivers in flood continued • The size and power of the river are both greatly increased, as is its carrying capacity • Almost all of the river hazards become much more dangerous during a flood and there are often additional hazards due to the flood • Flood waters are laden with debris, which can clog intakes and foul propellers on rescue boats • Trees and other large heavy objects join the river’s flow
Rivers in flood continued • Water flows through things on the flood plain like trees, fences, brush and debris, which greatly adds to the danger of being “strained” • As the river flows through “civilized” areas like streets, fields, and neighborhoods, the danger of contamination from pesticides, fecal matter, dead livestock, and ordinary household as well as industrial chemicals greatly increases
Rivers in flood continued • Eddies and eddy lines become a danger • Eddies are wide • Eddy fences are high and can become difficult to cross • The eddies themselves are rapidly-moving whirlpools from which escape is difficult
Site reference Downstream River Center Four river references relate to facing downstream River Right Current River Left Upstream
Site reference Upstream References remain the same even when the perspective is reversed River Right River Center Current River Left Downstream
Basic communication on the water • One whistle blast • Attention on me • Two whistle blasts • Attention upstream • Three whistle blasts • Attention downstream • Four or more whistle blasts • Attention on me, either myself or someone else is in trouble
Rescuer Safety Considerations The search of moving water is at best difficult and challenging. Such activities present great obstacles for swiftwater rescue teams and often expose searchers to the threat of personal injury or death.
Rescuer Safety ultimately depends on Training and Education“Common sense” may lead you astray!
Safe and effective search operations near moving water depend on proper... • Preparation • Training • Equipment
Hazards include... • Water hydraulics • Strainers(barb wire, tree limbs, log jams, debris) • Slippery, unsure footing • Topography(access, cliff faces, drop-offs) • Manmade obstructions(dams, bridges, debris) • Cold water
The safety of all personnel must always be the highest priority!
Rescuer/entrant priorities • Rescuer/entrant • Fellow team members • Victim • Property
Always use the SANE approach to swiftwater rescue! • Simple approach • Adequate backup • Never take chances • Eliminate the “beat the water” attitude
Any waterborne operation must be treated the same if the water environment poses a hazard to personnel entering the water. The situation does not have to be a rescue situation to be dangerous to the entrants.
Before any rescuer (entrant) enters the water always ensure that: • Upstream spotters are in place. • Downstream safety/containment teams are in place. • Rescuers have all of the appropriate safety gear on.
Associated risks to rescuers include... • Drowning • Entrapment • Hypothermia • Blunt trauma • Cuts and lacerations • Cold water shock
Public safety personnel that are untrained and ill-equipped to handle water-related emergencies, expose themselves to untold risks.Firefighters, law enforcement officers and members of the search and rescue community can all become victims during search and rescue events.
The role of search teams is to facilitate clue location... • Only personnel appropriately trained in swiftwater rescue should enter the water to recover any object. • Do not only focus on in water operations, many times victims exit the water on their own and need assistance but get overlooked initially because rescue teams focus on searching the water only • Have preplan in place for appropriate action prior to object location.
There is safety in numbers • Never search alone; search teams should consist of three or more person/teams (optimal). • Searchers should have knowledge of self-rescue and victim-rescue techniques. • Exercise caution, continually re-evaluate the Risk/Benefit Analysis and be prepared to assist teammates in an emergency. • Be properly equipped.
Shored-based Personal Protective Equipment • PFD with whistle & knife • Environmental protection • Gloves and boots • Throw line bags (at least 2 per person if available) • Helmet
Shored-based Personal Protective Equipment cont. • Remember • No bunker gear • No fire helmets • If you have a choice between no helmet and a fire helmet, go with no helmet. Fire helmets are designed to protect from falling debris, not falling down.
Water-based PPE for swiftwater rescue • Thermal protection • PFD with knife & whistle • Helmet • Swiftwater rescue board • Hand & foot protection • Fins/mask/snorkel • Throwline bags
Search equipment includes... • Probe device • Binoculars • Polarized sunglasses • Flagging & permanent marker • Rope and climbing equipment • GPS
Victim rescue • Scene assessmentSafety first Evaluate Risk/Benefit • Victim contactMake attempt to talk with victim • Always choose rescue methods that provide the highest degree of effectiveness while minimizing the risk to the rescuer.
As a rescuer... • Never tie yourself (or a victim) to a rope when working in moving water • Never tie a line across the river, perpendicular to the flow, in hopes of catching a victim • Never enter swiftwater wearing firefighter turnout or bunker gear
Rescue Methodsin order of preference... • Reach • Throw • Row • Go • Helo
“Reach” Method • Simple technique used when the victim is close to shore • Makes use of any object that can be extended to the victim for them to hold • Victim must be able to assist in rescue by holding on to object extended to them • Maintains high degree of safety for rescuer
“Throw” Method • Throw method is used when distance to victim exceeds ability to use the reach method • Method limited by distance and throwing accuracy of the rescuer • Victim must be able to assist in rescue by holding on to object thrown to them • Still maintains high degree of safety for rescuer
Water rescue throwline bags There is a right way... …and a wrong way.
Water rescue throwline bags • Throwline bags are a highly effective tool in swiftwater rescue • Easy tool to master but requires some practice • Dynamics of throw bag use:stay on shore stay on the move coach victim • Terrain considerations/victim access
“Row” Method • This method enables rescuers to close the gap between victim and the shore • Incorporates use of watercraft and allowing rescuers a safe approach to victim • A reach, throw or go rescue can now be attempted