Water quality in the Tweed River system has remained stable over the past 12 months according to Tweed Shire Council’s annual river report.
But it is far from a rosy picture with a number of waterways still achieving very low compliance scores, and annual rainfall in the river system continuing to be far less than the long-term average.
The Tweed River Report outlines the health of the Tweed River from high in the caldera down to the river mouth at Tweed Heads.
It shows that there has been no significant change in water quality between the 2018 and 2019 monitoring programs, with the exception of the Rous River, where the grade improved from ‘D’ to ‘C’.
A ‘C’ or ‘Fair’ designation is where there is an average of 50 to 60 per cent compliance with water quality objectives.
The Cobaki and Terranora Boradwaters achieved 87 per cent compliance with the objectives, while the Cobaki and Terranora tributaries achieved just 37 per cent compliance.
The Tweed, Oxley and Rous freshwater rivers achieved 68 per cent compliance, which the Upper Tweed Estuary from Chinderah upstream to Murwillumbah had just 61 per cent compliance.
The total annual rainfall for the 2018–2019 monitoring period was 1021mm, which is 65% of the long term average annual rainfall of 1,586mm. On a monthly scale, October 2018 was the only month where the long term monthly average was exceeded.