The drains in the Irrigation area are designed to

• Carry the high wet season flows from runoff within the Stage 1 area and adjacent areas including adjacent Crown land; Shire roads and reserves, airport, and private holdings.

• Remove excess tail water from on-farms irrigation watering.

• Convey operational "float" water from supply channels to the Ord River. The main channel and supply channels include provision for excess water to be diverted directly to the drainage system through waste-ways and relief points. Excess water is run to waste through these points for a range of operational reasons.

• The M1 Channel is also used to convey the Kununurra town treated effluent. This is diluted with the Diversion Dam releases into the M1 Channel and is either used in the on-farm irrigation water or flushed away through the M1W1 (wasteway) channel after periods when the M1 Channel has been drained and the effluent has pooled in the first section of channel.

The quality and quantity of irrigation drainage water is monitored on a regular basis to ensure that it’s potential impact on the environment of the Lower Ord is minimised.  A research bulletin produced by the National Program for Sustainable Irrigation in September 2005 concludes that the initial risk of loss of biodiversity which was considered a medium risk under current flows and medium to high risk under Ord Stage 2 flows, has been reconsidered and reduced to low under both scenarios for the majority of the river.