Water efficient technology and Crop switching Vs MAR system: Which is efficient for implementing true IWRM?

Barind area of Bangladesh is a water crisis area. The problems acute day by day. Integrated Water Resource Management (IWRM) project has been undertaken. We are working as follow the guideline of GWP and trying to get solution implementing appropriate context specific model.

"Boro rice" is most water consuming rice. We are motivating farmer to shift that crops with less water consuming crops  e.g: maize, wheat, tomato etc. Farmers also adopted it. (News 1 and News 2)

Beside the many intervention we also installed water efficient technology like AWD, drip irrigation etc.

We calculated that, replacing boro cultivation in 1 hectare of land with wheat, tomato, and fruits saves annually 1.6 million cubic metre of equivalent to 100’000 people’s annual domestic water need.

Interventions in agriculture have a much higher effect compared to the interventions above at HH level or the MAR system where there we talk about thousands of m3, while the agriculture related interventions we talk about millions of m3.

A question is that, Is MAR needed for establishing true IWRM? How are the impact? Though a little contribution, why we  invest a big budget to MAR compared to cost benefit analysis of agricultural intervention?