Your solutions to the Problems are not based on fact. A Shallow river with slow flow won't carry much water without breaking it's Banks. Where is a suitable place to build a dam deep enough to not have a high evaporation rate/volume held? Mt ISA DAM is 11 Metres deep and it is adversely affected by evaporation ( Can't be relied on as a water source.). The channel country provides the water for the lakes in Central Aust which are ALL salt lakes and only get water irregularly. Lake Eyre is below sea level and average depth only 1.5 Metres. The ONLY water that doesn't add salt is RAIN. Rivers become more salty as they drain more country. Irrigation concentrates the salt in places where it's used. It's inevitable UNLESS you drain the Block and pump the water to dry out in a shallow lake. That wastes a lot of soil nutrients as well and works better on fields with a bit of slope. The drainage system is costly and prone to blockages. You have to constantly MONITOR the depth of the Water Table. Water is too costly to over water. You have to do it sometimes in a Heat wave for example that may last for four days or More. Cotton, Rice and almonds are high water use crops that really should not be grown in semi desert areas. Nev