Legionella bacteria

Hi all.

We're planning a new water feature. The general idea is a small waterfall leading to a very shallow stream, ending in a tiny pool. Water will be pumped through a buried hose from the pool back to the top of the waterfall.

As the water will be moving, and therefore there's a chance of splashes and spray. As it will be super shallow, in summer it's very likely to hit the 20 degree minimum temp needed for legionella bacteria to grow.

Are there any wildlife friendly chemicals or other mitigation measures I can use to keep us from getting legionnaires disease?

Do I even need to worry about it? Maybe the risk is miniscule?

 

Can't say I've heard of this being a problem with garden water features. Cooling towers yes and some types of air conditioning. Legionella is not particularly infectious for fit healthy people, more of an issue if the immune system is compromised.
I would have thought that if it was an issue then suppliers would discuss it on their websites; I think I would talk to people who supply water features.
I did find these though Are Fountains and Water Features a Legionnaires Disease Risk? and Controlling Legionella in Decorative Fountains | CDC

 

I'm sure if it was a likely problem councils would be concreteing over every water feature that they can find.
Had a pond and water butts for many years and I'm still alive, but only just.