A number of southern Adelaide suburbs residents have noticed a change in the taste and smell of their tap water recently due to a change in the water treatment process.

Residents took to social media last week to voice complaints about developing rashes, skin irritations and upset stomachs after using or drinking water from the main water supply.

Many residents commented the water smelled strongly of chlorine and after showering or bathing in it, felt it had a similar strong smell as if they had been in a swimming pool.

SA Water responded to the concerns raised on social media, saying a different water treatment process had taken place at its Happy Valley Water Treatment facility recently due to managing an algal bloom at the Happy Valley Reservoir.

A statement said as of a result of this change in processes, residents would have noticed a slight change in the taste and smell of their tap water.

SA Water has been conducting additional water testing which indicated elevated levels of a naturally occurring compound however stated this was harmless to health.

SA Water has also been liaising closely with SA Health on the matter and stated its tests showed chemicals in the water were at a safe level.

However a number of residents have questioned if they can trust this information as they continue to experience a reaction to the water when showering, taking a bath or drinking it.

A Puratap spokesperson said the algal bloom would have most likely been a result of a higher concentration of nutrients in the River Murray due to recent flooding and storm water run-off.

“The warmer weather has created an ideal environment for algae to thrive,” the spokesperson said.

“This has seen a change in the water treatment process to manage this and in turn, a change in the taste and smell of the water for residents.”

The spokesperson said residents who had a Puratap water filter system in place would not have noticed a difference in the taste or smell of their drinking water, as a Puratap removes a large number of chemicals from tap water including chlorine and ammonia added in the water sanitation process.

“We have had people contacting us concerned about what the water is doing to their stomaches, if it is having this kind of reaction on their skin,” the spokesperson said.

“Our stomachs are full of beneficial bacteria for ‘good gut-health’ and all the chemicals that are added in the sanitation process are added to kill off bacteria such as algae so what effect is this having on your stomach?”

The Happy Valley Reservoir provides more than 40 per cent of the city’s water supply.

It is expected the current water treatment process will be ongoing until SA Water has effectively managed the algal bloom.