Recent rainfall good news for the health of the Selwyn river

Early this morning we became aware that the Selwyn River was flowing under SH1 for the first time in nearly three years following significant rainfall after an extended dry period.

As of this afternoon it has progressed further and is only around 9km from reaching Coes Ford to fully reconnect the river with Te Waihora / Lake Ellesmere.

This is good news for the health of the river and if it does fully reconnect it will help any eels / tuna in the flood flows trying to make their way to the sea.

It is a remarkable feature of these river systems that the flood front travels very slowly (currently around 1 km/hr) but just upstream the river is in full flood with velocities of 10-12 km/hour.

This is because the flood front is filling up the air spaces in the gravels and recharging groundwater.

It is likely that the river will dry up again across the plains in the next few weeks but this flow makes it much easier for the river to reconnect with smaller rain events in autumn, winter and spring.

If it does dry up again in the future please keep an eye out for any stranded eels and get in touch with us so we can co-ordinate a response.  

You can find key zone contact information here.