Water as a right
Grandfathered water usage laws that treat water as a commodity underminds the water as a right responsible usage law structure. This is where you must buy your water from the water authority as a service and if you do not pay your bill they shut off your water.
Solutions that work in other places are buying all of the rights from the owners and then reselling the whole commodity to the redesigned IWRM like model.
But this is only a reaction to the already implemented solutions treating it as a commodity where if we truly where to implement a sustainable responsible water management system it would not treat water as a commodity but more like a right, with over-usage fees, applying integrated inputs of energy, diverse methods of filtration/sourcing/and distribution, public private partnerships, also taking into account multiple management authorities in conflict susceptible areas so that modification to systems are from the divisive stakeholders.
More robust in that each part of the water infrastructure has an alternative. Have two sources of water such as ground water and surface water.
Have two of pumping power sources.
Think of the water infrastructure as the best possible implementation; do not be detoured, limited , skewed solution because of the necessity to retrofit existing infrastructure.
Cost of Waste in IWRM systems.
How can you get peoples habits to assure responsible usage to help the overall management of a resource?
Food production nexus relating the product's cost with its whole supply chain cost for something such a banana to the cost of a wasted banana.