All I have asked you to do is to back up the comments that you have made - which you have struggled to do.
Given what farmers have to invest in the irrigation scheme and what they pay on a yearly basis to keep it running, I'm not convinced that it would 'double their land values overnight'. But then I'm not a Canterbury land agent, you might be?
But I will answer your question....
The government is currently building 'Transmission gully' and a motorway that will run from Wellington to north of Levin. This in effect makes the Kapiti coast and Horowhenua a lot closer to Wellington in terms of travel time. The area is becoming even more popular with people working in Wellington because of the shorter commute. The region is growing, businesses are relocating here and jobs are being created. As a result house prices are moving up significantly.
To be clear, the government are not doing this to increase the values of peoples houses, they are doing it to create efficiency and to stimulate growth. The increase in house prices is a positive externality.
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