Local Govt | National News Video | Parliament Headlines | Politics Headlines | Search

 


Water storage lake to be drained

Water storage lake to be drained

Greater Wellington Regional Council has this week begun draining one of its water storage lakes, in an effort to remove an organic compound, recently found at higher than normal levels in the lakes.

The naturally occurring compound, known as Geosmin, can cause water to taste and smell ‘earthy’. Geosmin poses no health risk and the water remains safe to drink.

Lake water with normal levels of Geosmin is routinely treated at the Te Marua Water Treatment Plant using powdered activated carbon (PAC). However due to the exceptionally high levels in Lake 2 in recent weeks, not all of this taste and odour causing compound can be removed from its water. The level of Geosmin in Lake 1 is presently normal, which means that the PAC treatment is able to effectively remove the Geosmin.

Because storage lake water is only used as a back-up water source when river water is unavailable (for example, after heavy rainfall when river water is too dirty to treat) and water from Lake 1 is able to be used, regional council officers have made the decision to drain Lake 2 and refill it with fresh water.

Greater Wellington Regional Council Water Supply General Manager Chris Laidlow says that while all water being supplied to the public remains completely safe to drink, it made sense to drain the lake.

“When we’re using water from the storage lakes – which isn’t often – organic compounds such as Geosmin are removed using PAC. While that process sometimes doesn’t remove all of the compounds from our water, it is completely safe and complies with the NZ Drinking-water Standards.

“We decided this week that it is better to drain Lake 2 rather than continue to try and treat the high levels of Geosmin. Now is a reasonable time to empty the lake as there is a very low risk of a water shortage at this time of year and we have plenty of time to refill the lake before next summer.

“We don’t yet know the cause of the high levels of Geosmin but we’re looking into this and also methods for dealing with high levels of Geosmin in the future.”

Lake 2 is the southern of the two lakes and holds 2,067 million litres of water. It will be empty by 20 May and is expected to take 6-8 weeks to refill.

Ends

© Scoop Media

 
 
 
 
 
Parliament Headlines | Politics Headlines | Regional Headlines

 

PARLIAMENT TODAY:

Arming Police: Frontline Police To Routinely Carry Tasers

"In making the decision, the Police executive has considered almost five years worth of 'use of force' data… It consistently shows that the Taser is one of the least injury-causing tactical options available when compared with other options, with a subject injury rate of just over one per cent for all deployments." More>>

ALSO:

Gordon Campbell: On D-Day For Dairy At The TPP

While New Zealand may feel flattered at being called “the Saudi Arabia of milk” it would be more accurate to regard us as the suicide bombers of free trade. More>>

ALSO:

Leaked Letter: Severe Restrictions on State Owned Enterprises

Even an SOE that exists to fulfil a public function neglected by the market or which is a natural monopoly would nevertheless be forced to act "on the basis of commercial considerations" and would be prohibited from discriminating in favour of local businesses in purchases and sales. Foreign companies would be given standing to sue SOEs in domestic courts for perceived departures from the strictures of the TPP... More>>

ALSO:

"Gutted" Safety Bill: Time To Listen To Workplace Victims’ Families

Labour has listened to the families of whose loved ones have been killed at work and calls on other political parties to back its proposals to make workplaces safer and prevent unnecessary deaths on the job. More>>

ALSO:

Regulators: Govt To ‘Crowd-Source’ Regulatory Advice

A wide-ranging set of reforms is to be implemented to shake up the way New Zealand government agencies develop, write and implement regulations. More>>

ALSO:

Board Appointments: Some Minister Appoint Less The 3 In 10 Women

“It’s 2015 not 1915: Ministers who appoint less than 3 in 10 women to their boards must do better, they have no excuse but to do better,” said Dr Blue. More>>

Gordon Campbell: On The 1990s Retro Proposals For Our Health System

As we learned yesterday, the reviews propose that the democratically elected representation on DHBs should be reduced, such that community wishes will be able to be over-ridden by political appointees. In today’s revelations, the reviews also propose a return to the destructive competitive health model of the 1990s. More>>

ALSO:

Get More From Scoop

 

LATEST HEADLINES

 
 
 
 
 
 
 
 
 
Regional
Search Scoop  
 
 
Powered by Vodafone
NZ independent news