Must be getting pretty hard to justify having water use restrictions in Auckland when dams are 87% full, and heaps of extra capacity has now come online.

Jase2985:

 

Given that the Waitaks have been full for a while now, could we not be using more water from them as they seem to fill faster to help the hunuas recover?

 

and with the hunua's could water not be transferred or used from the full ones?

 

How hard would it be to make extra reservoirs in the hunua's or waitaks?

 

"Our current water sources
At the moment, with Auckland still recovering from 2020's severe drought, we are minimising production at our Ardmore Water Treatment Plant, which treats water from our four Hūnua dams, and maximising production at our Waikato water treatment plants, where we treat water from the Waikato River. This eases the pressure on our Hūnua dams, allowing them to fill up as much as possible when it rains."

https://www.watercare.co.nz/Water-and-wastewater/Water-supply-situation

There are capacity limits to treatment plants, so there is a point where you are maxing out all you can in this regard. 

I think a lot of the pipes in from the dams are gravity fed, so only run one way. And there may be environmental concerns about mixing the water. Anyway in the Hunua's, the only full dam is the tiny Hays Creak one. All the big four dam's in the  Hunua's are in the 79 - 87% range, so aren't too unbalanced.

In terms of more storage capacity, as a whole Auckland has a lot of Dam capacity. Currently at 87% or 83GL. Daily consumption target at the moment is 420ML, so 197 days even with zero inflows (or using the waikato / springs). Clearly heaps to buffer seasonal demand, and even a dry year (but we start freaking out if we have two in a row).

What Auckland needs is more inflows. In short, the long term plan for Auckland water is to just take more and more from the waikato. Luckly that river even at periods of flow has a near infinite amount of water compared to Auckland needs. Since the drought issues, watercare scrambled and brought online some sources (A spring and a previously decommissioned dam) that would not have been economic in the long term plan, but could be spun up quickly.

• Completed the Pukekohe East reservoir, a key project enabling our Waikato Water Treatment Plant to treat up to 175 million litres a day (MLD)
• Completed the Waikato 50 plant in record time, taking our peak production from the Waikato River to 225 million litres a day
• Built a new Pukekohe Water Treatment Plant, which treats up to 5MLD
• Built the first stage of our Papakura Water Treatment Plant, which treats up to 6MLD
• Upgraded our Onehunga Water Treatment Plant, boosting treatment capacity by 4MLD
• Carried out acoustic leak detection on more than 5,500 kilometres of our water network to find and fix invisible leaks. This has saved an estimated 9MLD.