--- Update: Lake Rua is open for use again ---

After the Christchurch Earthquakes, we were reminded that heavy rainfall is likely to wash contaminants into our waterways. In that case it was from the damaged "horizontal infrastructure" which meant that sewage in/on the land was getting washed into the Avon and Kaiapoi etc. Well, that is mostly fixed now, however it is still something to bear in mind if we have heavy and/or sustained rainfall around our rivers.

And now we have seen that the sudden Thunderstorm on Thursday dropped significant rain that caused relatively fast run-off. As a result, for the first time we have seen Te Whatu Ora (Health New Zealand) issue a health warning after high levels of faecal bacteria were found in samples taken from Lake Rua. The Park Ranger tells us that this week's lake water sampling (26 Dec 2024) has resulted in a warning, following that heavy rainfall which is typically when bacteria samples show as being higher.

Update: apparently, the Lake was still closed on Sat 4 Jan 2025, but opened the day after that, so all training etc may continue.

Note, contamination levels are likely to be similar at other swimming sites (and Rivers) as well. Te Whatu Ora advise that this may be the case for 48 hours after rainfall.

It is really the teams' call whether they go out training, but the main risk is really for swimming or people getting IN the water, not ON the water.

This contamination/polution should clear up quickly, especially once the rain eases and surface water can be absorbed straight into the ground, and lakes and rivers get purged by natural flows.