75 by 35, biosolids workshop

Water New Zealand Conference & Expo 2026

75 by 35

Shaping New Zealand's biosolids
to carbon neutrality

Water New Zealand Wastewater SIG
Biosolids Sub-Group

Tue 22 September 2026 · 2:00 to 3:30pm · Arena Lounge

Before we start

Pin your place on the map of Aotearoa

Take a commitment sheet, keep it beside you

Sit at the tension table closest to your work

We open with karakia, Kia hora te marino, at 2:00

75 by 35 · Water New Zealand Conference & Expo 2026

01 / 14

Karakia tīmatanga2:00

Kia hora te marinoMay peace be wide-spread

Kia whakapapa pounamu te moanaMay the sea be like greenstone

Hei huarahi mā tātou i te rangi neiA pathway for us all this day

Aroha atu, aroha maiGive love, receive love

Tātou i a tātou katoaLet us show respect for each other

Haumi ē, hui ē, tāiki ē!Bound together, we move as one

75 by 35 · Water New Zealand Conference & Expo 2026

02 / 14

The agenda we are holding

Ten minutes presented,
seventy minutes of work

2:00

Karakia, welcome, get settled

10 min

2:10

State of play: tonnes, bill, carbon

10 min

2:20

The three tensions, at your table

45 min

3:05

What did we learn, what happens next

13 min

3:18

Commitments, then karakia whakamutunga

12 min

Three tables run at once through the 45-minute block:
Technology & Economics · Political & Social · Legal & Environmental

75 by 35 · Water New Zealand Conference & Expo 2026

03 / 14

State of play · where it goes2:10

Only 17% of our biosolids reach productive land

Today · 2023 survey

0productive

Productive land

17%

Landform and bulk fill

43%

Landfill and capping

32%

Stockpiled

2035 · the target

0productive

Productive land

75%

Other pathways

15%

Landfill

10%

Today: ANZBP New Zealand Biosolids Survey 2023 (plants over 25,000 PE), published January 2024. Dry-mass basis, rounded; landfill includes 2% landfill capping.
Target: the split beyond the 75% is ours to set, it is not in the survey.

75 by 35 · Water New Zealand Conference & Expo 2026

04 / 14

State of play · the bill and the carbon2:13

Cutting landfill cuts the bill and redirects carbon

TODAY · 2026

A big bill

for burying what we could use

2035 · DO NOTHING

A bigger bill

if we carry on as we are

2035 · LANDFILL AT A TENTH

A smaller bill

and the carbon falls with it

Today · 2026

Highest

2035 · do nothing

Higher

2035 · 75 by 35 as drawn

About the same

2035 · landfill at a tenth

A fraction

75 by 35 · Water New Zealand Conference & Expo 2026

05 / 14

State of play · what holds us back2:16

Three tensions stand between 17% and 75%

Technology & Economics

Plant scale and technology fit

Capex, opex and cost per tonne

Product quality and haulage distance

Political & Social

Grower and farmer willingness

Iwi and community expectations

Mandate, ownership and risk

Legal & Environmental

Consent conditions and guidelines

Contaminant limits, PFAS and microplastics

Monitoring and evidence base

0Today

0By 2035

75 by 35 · Water New Zealand Conference & Expo 2026

06 / 14

Biosolids recovery roadmap2:17

One journey to a yes, in three stages

1Business case

Build the case for land

Size the volume

Test the quality

Find the land

Weigh the cost

2Technical assessment

Grade the product, test the land

Grade the product

Test the land

3LGA process

Get to a yes

Engage stakeholders

Prepare the case

Consult the public

Apply for consent

Three stages, one destination: 75% to productive land by 2035

75 by 35 · Water New Zealand Conference & Expo 2026

07 / 14

Roadmap · stage 1 · business case2:18

Four checks decide go or no-go

Size the volume

What we make now, and how it grows.

Test the quality

Metals, pathogens, nutrients and PFAS.

Find the land

Candidate sites, and the hectares needed.

Weigh the cost

The investment against cartage, levy and business as usual.

Does not stack up

Alternative processing or disposal

Stacks up

Preferred site into the technical assessment

75 by 35 · Water New Zealand Conference & Expo 2026

08 / 14

Roadmap · stage 2 · technical assessment2:19

The product grade has to meet the land test

The product grade

Cleanest, best treated, widest use

Good, with more conditions

A2 / B2

Restricted, tighter controls

None

Pathogen or VAR non-compliant, prohibited

The land test

Soil pH and chemistry

Slope

Nutrient loading

Set-backs

Safe storage

Groundwater depth

Permitted

Straight into the LGA process

Controlled

Into the LGA process with conditions

Prohibited

Alternative processing or disposal

75 by 35 · Water New Zealand Conference & Expo 2026

09 / 14

Roadmap · stage 3 · Local Government Act process2:20

Elected members make the call

Engage

Mana whenua

Immediate neighbours

Wider stakeholders

Prepare

Soil testing

Planning pathway

Decision reports

Consult

Public consultation

Submissions heard

Council reports back

Elected members decide

Proceed

Prepare the AEE and lodge for consent

Cease

Iterate the case, or seek alternatives

75 by 35 · Water New Zealand Conference & Expo 2026

10 / 14

Over to you · 2:20 to 3:0545 min

The roadmap is the map.
Now we pressure-test it.

Technology & Economics

What tech or cost barrier blocks reuse before a CCO commits capital?

Political & Social

What makes reuse normal, and who holds the mandate but is not using it?

Legal & Environmental

Where does the framework block or enable reuse, and what does the evidence say?

Barriers and enablers on the sheet

One accountable task each, a name and a date

Name the carbon consequence of every barrier

75 by 35 · Water New Zealand Conference & Expo 2026

11 / 14

Reference board · stays up while you work2:20 to 3:05

Find your lever, name the constraint, discuss

Technology & Economics

Political & Social

Legal & Environmental

Leverswhat we can change

Thickening and dewatering

Drying

THP + AD

Energy recovery

Pyrolysis

Asset management plans

Procurement and offtake

Engagement approach

Trade waste source control

Product grading

Land application controls

Emissions and odour control

Soil loading limits

Constraintswhat stands in the way

CapEx

OpEx

Funding

Delivery risk

Political cycle

Community expectation

Market acceptance

WEPS

RMA and LGA

Regional rules

Consenting pathway

Actorswho decides

Technology providers

CCO boards

Asset managers

Mana whenua

Council and elected members

Local community

Farmers and landowners

Taumata Arowai

Ministry for the Environment

Regional councils

Landowners

75 by 35 · Water New Zealand Conference & Expo 2026

12 / 14

Harvest · 3:05 to 3:1813 min

We turn the sheets into a mandate

1Read back the themes

Three to five themes that kept coming back on your sheet.

2Dot vote

Two dots each, a barrier and what would unlock it.

3Next 90 days

What happens before Christmas, and who is holding it.

The most actionable statements become the working group mandate

75 by 35 · Water New Zealand Conference & Expo 2026

13 / 14

Commitments board · 3:18 to 3:25

One commitment each,
back to our own communities

I
          from
commit to
completed by
          email

Photographed and shared with every participant within 48 hours

75 by 35 · Water New Zealand Conference & Expo 2026

14 / 14

75 by 35

Before we start

Ten minutes presented,seventy minutes of work

Only 17% of our biosolids reach productive land

Cutting landfill cuts the bill and redirects carbon

Three tensions stand between 17% and 75%

One journey to a yes, in three stages

Four checks decide go or no-go

The product grade has to meet the land test

Elected members make the call

The roadmap is the map.Now we pressure-test it.

Find your lever, name the constraint, discuss

We turn the sheets into a mandate

One commitment each,back to our own communities

75 by 35

Before we start

Ten minutes presented,seventy minutes of work

Only 17% of our biosolids reach productive land

Cutting landfill cuts the bill and redirects carbon

Three tensions stand between 17% and 75%

One journey to a yes, in three stages

Four checks decide go or no-go

The product grade has to meet the land test

Elected members make the call

The roadmap is the map.Now we pressure-test it.

Find your lever, name the constraint, discuss

We turn the sheets into a mandate

One commitment each,back to our own communities

Ten minutes presented,
seventy minutes of work

The roadmap is the map.
Now we pressure-test it.

One commitment each,
back to our own communities

Ten minutes presented,
seventy minutes of work

The roadmap is the map.
Now we pressure-test it.

One commitment each,
back to our own communities