Like a lot of infrastructure in New Zealand, Palmerston North’s wastewater system is aging. At the same time it’s under increased pressure from a growing population, and higher expectations around discharge standards and river water quality.

What do you think is important in the treatment and discharge Palmerston North's wastewater?

Nature Calls will investigate the full range of options for managing, treating and discharging wastewater. As of November 2018, all options are on the table.

Palmerston North City Council has commissioned specialist consultants to work with them to identify a longlist of possible options – this is a starting point.

Once the longlist has been established, towards the end of 2018, the process of assessing and narrowing them down will begin. Phase 1 of the assessment of options will be to narrow the longlist to a shortlist.

To identify options for Nature Calls, there are a few things to consider: how and where wastewater is DISCHARGED, how wastewater is TREATED, and where the treatment plant is located.

Because discharge is critical to potential environmental, social and cultural effects, the development of the options list has begun with identifying the range of potential receiving environments for treated wastewater. Your feedback is welcome.

The main treated wastewater discharge options are:

• To land – all the time
• To surface water (Manawatū River) – all the time
• To surface water – all the time, discharge split between locations
• To groundwater (Managed Aquifer Recharge process) – all the time
• To coastal water (South Taranaki Bight, Tasman Sea) – all the time
• A mixed scheme – coastal water and surface water
• A mixed scheme – land and surface water (sub-options with varying mix of land and surface water)
• Combinations of the above

In addition to the main components which will make up the longlist options, it is recognized that all options could involve elements which:

• reduce wastewater generation
• improve the efficiency of wastewater collection
• re-use some or all of the treated wastewater or byproducts from the wastewater treatment process

• ENM has begun liaison with member groups, to contribute to this project on behalf of the network.