WCA acting CEO Luke Austin said a series of factors contributed to the river's appearance.

"There was some discussion over the Christmas break about the quality of water in the weir pool," he said.

"That's been raised by the ongoing dry, a long and shallow river, and the banks of clay contributing to the discolouration of the water.

"The way the clay interacts with the water leads to discolouration in and around Horsham, whereas downstream from Horsham, you have sandy banks, so the water looks clearer."

Mr Austin however said there was no cause for concern.

"We are monitoring it, but we're fairly comfortable with where things are at," he said.

"We weren't aware of any risk (to flora and fauna), and we were keeping an eye on it (over the Christmas and New Year period).

"We do also have some water flow for the environment due to commence on Monday, and we're continually monitoring the situation."

Mr Austin said water would flow from Taylors Lake to help maintain water levels and "freshen up" the river.

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He said the WCA was also "closely monitoring" rain from the weekend which had increased levels in the upper catchment.

"We have seen some of that water come through the river, and we're waiting to see what flows we get," he said.

Mr Austin said the WCA, GWM Water and Horsham Rural City Council leaders were also set to meet to discuss the issues observed over December.

Horsham Rural City mayor Robyn Gulline said she sympathised with resident's concerns, but that diligent management processes were in place to have the "iconic" river in good shape.

"It is important that the river is managed well, but I understand it is a very complex issue," she said.

"I'm looking forward to meeting with the Wimmera Catchment Authority and GWM Water to discuss the management of the river and lakes so I can better understand the complexity.

"Council is also spending millions activating and beautifying the riverfront - it's an incredibly important part of the region and it's vitally important that it is well managed."

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