GENERAL HAZARDS

Cold water

Cold water can rapidly weaken a person's swimming ability, cause confusion and a deterioration in the persons decision making ability. Some risks related to this hazard include hypothermia and cold-water shock. Prolonged exposure in cold water will cause the body to gradually shut down.

Deep water

Deep water is a hazard for many people. People drown every year as a result of immersion in water that is deeper than they anticipated. In deep water, people will have  reduced ability to keep their head above water which may increase the risk of drowning.

Rainfall & flooding

Flooding is the most common natural disaster in Australia. On average, eight (8) Australians drown due to flooding each year.

There are many inland waterways that only have water in them during flood events. Thus, these rain events can result in a sudden dramatic increase in water levels in lakes and rivers. In these circumstances, not only can the water levels rise, but the behaviour of the water can change considerably. Currents become faster and stronger and can move submerged and floating objects with them.

Additional hazards that may be present during flooding events:

• Mud
• Trees may fall as saturated soil can no longer support the weight of the tree
• Contact with sharp objects hidden by flood water
• Water contamination from fuel oils, sewerage systems, fertilisers and other chemical contaminants
• Animals being displaed and/or looking for high/dry ground
• Open manhole covers hidden by the flood waters
• Electrocution from submerged power lines and other electrical systems
• Liquid petroleum gas cylinders damaged by water flow may cause an explosive atmosphere as heavier air vapour pools in low lying areas
• Building collapse caused by the failure of footings or the force of flowing water

Shallow water

The main risk associated with shallow water is the risk of a collision with the bottom of the riverbed or lakebed. This is particularly problematic where there is reduced water visibility. Sadly, there are many people who have become quadriplegic from diving into shallow water.

Slippery rocks and surfaces

Water will often make surfaces slippery. This is especially true for rocks, wood and concrete often found beside inland waterways. In addition, water will often encourage the growth of moss and lichens that make surfaces slippery. Slippery surfaces are hazardous due to the risk of injury from falling and sudden immersion.

Snow and ice

Areas where water sources may freeze over in winter, such as the alpine region, are hazardous. Snow can be unstable and difficult to walk on, which increases the risk of falls. Ice is especially dangerous because it is slippery and may break apart, causing falls or submersion into cold water. The hard surface also increases the likelihood of injury after falling.

Sudden drop offs-land

Many inland waterways, either man-made or naturally occurring, have banks, cliffs, or levees with a sudden edge that people can fall over and into water. This presents two main hazards. The first is the nature and length of the fall. The second is if the person falls into water and is unable to keep their head above water. Falling into shallow water increases the risk of injury through striking the bottom. Falling into deep water increases the risk of the person being out of their depth or being knocked out and entering the water in an unconscious or semi-conscious state.

Sudden drop offs-water

A sudden change in the depth of water can lead to people finding themselves unexpectedly in deep water. If an individual finds themselves out of their depth and does not have the swimming ability to get back to shore safely they are at a higher risk of drowning.

Tides

The rise and fall of water in rivers due to tides can be hazardous for many reasons. A rising or high tide can increase water flow, move sediment and increase water levels. Low or falling tides can lead to less water, a change of flow and submerged objects being realised where they were previously absent.

Toxic contaminated water

Water quality can have a significant effect on the health and safety of the community. Poor water quality can stem from many sources such as wash off, which may contain litter, chemicals, disease, other debris and faecal matter. This is particularly relevant after a heavy rain event as water quality may be impacted for several days. Water quality may also be compromised from a blue green algal breakout, caused by high levels of nitrogen in fertilizers that have been washed into the water, or pollution from a chemical spill. These contaminants can cause mild to severe health issues which may include injury or infections related to ears, nose, skin and/or gastrointestinal issues.

Uneven bottom

Uneven riverbeds or lakebeds are a hazard to those who are not intending to go into the water as the unevenness may cause individuals to become unexpectedly immersed in water. Unexpected immersion, especially for weak or non-swimmers, increases the risk of drowning.

Unstable riverbanks or waterbeds

A crumbling riverbank can lead to an accidental fall in or into the water. Falls are a common occurrence in and around waterways which can lead to drowning after unexpected immersion. Some shorelines or waterbeds may also be composed of silt or soft sediment which may put someone at risk if the individual is unable to pull themself out of the silt, soft sediment or quicksand.

Vegetation

There are three ways vegetation can be considered a hazard in and around inland waterways.

Firstly, vegetation can be hazardous in waterways if a person becomes caught and is unable to free themselves.

A second reason why vegetation can increase drowning risk is that it often occludes the edge of the water body. This can lead to a situation where somebody becomes accidentally immersed as they were unaware of where the land ended and where the water began.

Lastly, some vegetation may have sharp and/or poisonous leaves or thorns that can cause injury or illness.

Water clarity

Water clarity can be a hazard closely associated with water quality, shallow water and submerged objects. Water clarity may not pose a significant risk by itself, but it may serve to hide other, more significant dangers such as shallow water or submerged objects. Water clarity may also serve as an indicator for poor water quality.

Wind

The wind is not an obvious hazard associated with inland waterways; however, it can present significant danger in several ways. Firstly, wind impacts watercraft such as dinghies, small sail boats and other inflatable craft. The wind can blow these craft off course and away from safety. Strong gusts of wind can also cause watercraft to capsize, resulting in unexpected and sudden immersion. A secondary hazard associated with wind is the effect that wind has in ruffling the surface of the water. This can impact visibility and reduce water clarity, hiding submerged objects and hazards.