issue 64 newsletter feb 2020 nz land treatment collective ...wastes and land applied livestock...

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Inside this issue: Update from NZLTC Chair and Technical Manager 1 NZLTC 2020 Conference 2-3 Onsite Wastewater Management Systems (OWMS) workshop 4-5 Department of Conservation: Waste management on a Great Walk 6 The Darfield Onsite Wastewater Management Story 7-8 Managing stormwater on land to protect surface water 9 NZLTC Resources - Northwest Biosolids 10-11 NZ Land Treatment Collective NEWSLETTER Dedicated to improving and communicating research and technology for the land treatment of waste Kia ora everyone Preparations for our annual NZLTC conference are in full swing! The NZLTC Technical Committee are really looking forward to reconnecting with the wide range of conference delegates that attend every year. The conference always provides a ‘boutique’ experience for our land treatment community where networking opportunities are plentiful alongside an atmosphere of camaraderie within our small group. We encourage you to register and take advantage of the opportunity to connect and learn. For the registration link please click here. We are pleased to announce that Dr Mark Borchardt from the US Department of Agriculture has been confirmed as our International keynote speaker. Mark is an excellent communicator and his research includes septic system wastes and land applied livestock manure as related to pathogen contamination of groundwater and human health risks. His keynote address will be highly relevant to the many land treatment challenges that NZ faces. This newsletter contains information on: NZLTC annual conference 31 March—2 April 2020 Palmerston North (page 2-3) Onsite Wastewater Management Systems (OWMS) workshop 30 March 2020 Palmerston North (page 4-5) Department of Conservation - Onsite waste management challenges (page 6) The Darfield Onsite Wastewater Management Story - Canterbury (page 7-8) Managing stormwater on land (page 9) Northwest biosolids resources: cannabis and nitrous oxide (page 10-11) Ngā mihi nui Grant Northcott (NZLTC Chair) and Bronwyn Humphries (NZLTC Technical Manager) Update from the NZLTC Chair and Technical Manager Issue 64 Newsletter Feb 2020 https://nzltc.wordpress.com/ 1 The Routeburn Track one of New Zealand’s Great Walks - On-site Wastewater Management System (OWMS) at Routeburn Falls Hut

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Page 1: Issue 64 Newsletter Feb 2020 NZ Land Treatment Collective ...wastes and land applied livestock manure as related to pathogen contamination of groundwater and human health risks. His

Inside this issue:

Update from NZLTC Chair and

Technical Manager

1

NZLTC 2020 Conference 2-3

Onsite Wastewater Management

Systems (OWMS) workshop

4-5

Department of Conservation:

Waste management on a Great

Walk

6

The Darfield Onsite Wastewater

Management Story

7-8

Managing stormwater on land to

protect surface water 9

NZLTC Resources - Northwest

Biosolids 10-11

NZ Land Treatment Col lect ive

NEWSLETTER

Dedicated to improving and communicating research and technology for the land treatment of waste

Kia ora everyone

Preparations for our annual NZLTC conference are in full swing! The NZLTC Technical

Committee are really looking forward to reconnecting with the wide range of

conference delegates that attend every year. The

conference always provides a ‘boutique’ experience for

our land treatment community where networking

opportunities are plentiful alongside an atmosphere of

camaraderie within our small group. We encourage you

to register and take advantage of the opportunity to

connect and learn. For the registration link please click

here.

We are pleased to announce that Dr Mark Borchardt from the US Department of

Agriculture has been confirmed as our International keynote speaker. Mark is an

excellent communicator and his research includes septic system

wastes and land applied livestock manure as related to pathogen

contamination of groundwater and human health risks. His keynote

address will be highly relevant to the many land treatment

challenges that NZ faces.

This newsletter contains information on:

NZLTC annual conference 31 March—2 April 2020 Palmerston North (page 2-3)

Onsite Wastewater Management Systems (OWMS) workshop 30 March 2020 Palmerston North (page 4-5)

Department of Conservation - Onsite waste management challenges (page 6)

The Darfield Onsite Wastewater Management Story - Canterbury (page 7-8)

Managing stormwater on land (page 9)

Northwest biosolids resources: cannabis and nitrous oxide (page 10-11)

Ngā mihi nui

Grant Northcott (NZLTC Chair) and Bronwyn Humphries (NZLTC Technical Manager)

Update from the NZLTC Chair and Technical Manager

I ssue 64

Newslet ter Feb 2020

https://nzltc.wordpress.com/

1

The Routeburn Track one of New Zealand’s Great Walks - On-site Wastewater Management System (OWMS) at Routeburn Falls Hut

Page 2: Issue 64 Newsletter Feb 2020 NZ Land Treatment Collective ...wastes and land applied livestock manure as related to pathogen contamination of groundwater and human health risks. His

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Monday 30 March Tuesday 31 March

General land treatment and

OWMS focus

Wednesday 1 April

General land treatment and

agricultural focus

Thursday 2 April

Workshop

On-site Wastewater

Management (OWMS)

- all key stakeholders to dis-

cuss what is working and what

isn’t

- progress a plan for the future

Conference - Day 1

International keynote -

Mark Borchardt (USDA)

Local keynote - Hori-

zons Regional Council

National keynote - TBC

Delegate presentations

Conference - Day 2

National keynote - TBC

Delegate presentations

Fieldtrip

Palmerston North - land

treatment locations

Evening Events

Social function

Brew Union Brewing

Company (craft beer,

pizza and spot prizes)

Conference dinner and

awards

TBC

Premier sponsors

Break sponsor Award sponsor

Northcott Research

Consultants Ltd.

Student Scholarship sponsor

Lunch sponsor

Page 3: Issue 64 Newsletter Feb 2020 NZ Land Treatment Collective ...wastes and land applied livestock manure as related to pathogen contamination of groundwater and human health risks. His

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Trade Displays

The NZLTC are inviting exhibitors to purchase a trade display area. This is an ideal opportunity to showcase your business

and land treatment technologies.

sites are $500 each

10 sites available

Contact Bronwyn Humphries (NZLTC Technical Manager) to secure your site

[email protected]

Important dates

Registrations and abstracts are now open

Abstracts close - 21 Feb 2020

Authors notified—28 Feb 2020

Full papers due - 25 Mar 2020

OWMS Workshop - 30 Mar 2020

NZLTC AGM - 31 Mar 2020

NZLTC Conference - 31 Mar - 2 Apr 2020

Sponsorship To view our conference sponsorship opportunities click here:

International Keynote

Dr Mark Borchardt is a microbiologist who works for the US Agricultural Department (USDA) in

Wisconsin.

His research includes septic system wastes and land applied livestock manure as related to pathogen

contamination of groundwater and human health risks. [email protected]

Venue accommodation rates

To view options click here:

Online conference registration click here:

Key conference information

NZLTC AGM

The NZLTC AGM will be held at the Distinction Coachman Hotel, Palmerston North at 4:30pm, Tuesday 31 March 2020

NZLTC Social Evening - Tuesday 31 March

The social evening will be held at the Brew Union Brewery. Names will be collected via business cards during the evening

and the event sponsor will draw out winners for some quality prizes plus a few humorous ones.

Page 4: Issue 64 Newsletter Feb 2020 NZ Land Treatment Collective ...wastes and land applied livestock manure as related to pathogen contamination of groundwater and human health risks. His

All stakeholders

On-site Wastewater Management Systems

(OWMS) workshop

Monday 30 March 2020

9:30am – 4:30pm

Distinction Coachman Hotel

Palmerston North

Brought to you by:

Small Wastewater and Natural Systems - Special Interest Group (SWANS-SIG)

and

NZ Land Treatment Collective (NZLTC)

Purpose: For stakeholders to identify core OWMS issues in New Zealand

(i.e what’s working and what isn’t)

Outcomes:

1) Document outlining the OWMS issues as identified by each sector

2) Create a network of key stakeholders to be involved in future discussions

3) Set the agenda for a second workshop in the future to help address some of the issues

Format: Specialists from each industry sector have been invited to make 15 min presentations focused on

core OWMS issues followed by 10 mins Q and A.

For more information please contact:

Joint SWANS-SIG Chairs

Sandy Ormiston [email protected]

Trisha Simonson [email protected]

NZLTC Technical Manager

Bronwyn Humphries [email protected]

WaterNZ member: $60

NZLTC member: $60

Other: $120

Register online: Click here

If you are a WaterNZ member please

get in touch with:

[email protected] for the

discount code

4

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Welcome to Workshop and Outline of Objectives

9:30-9:45 Sandy Ormiston

Industry Sector: Designers

9:45-10:00 Andrew Dakers (Eco-Eng)

10:00-10:15 John Cocks (John Cocks Limited)

10:15-10:25 Questions/Discussion

10:25-10:45 Morning Tea

Industry Sector: System Suppliers

10:45-11:00 Brent Hawthorn (Innoflow Technologies)

11:00-11:15 Mike Dawson (Hynds)

11:15-11:25 Questions/Discussion

Industry Sector: Installation and Maintenance

11:25-11:40 Craig Rall (Envirolutions)

Industry Sector: Irrigation

11:40-11:55 Bruce Richter (Netafim)

11:55-12:05 Questions/Discussion

Industry Sector: Regulators

12:05-12:20 Keith Peacock (Hawkes Bay Regional Council)

12:20-12:35 Leif Piggott (Tasman District Council)

12:35-12:45 Questions/Discussion

12:45-1:25 Lunch

Industry Sector: OSET-NTP

1:25-1:40 Ray Hedgland (OSET Technical Manager)

Industry Sector: Training

1:40-1:55 Brett Marias (WSP Training)

Industry Sector: End-User

1:55-2:10 Peter Carter (Department of Conservation)

2:10-2:20 Questions/Discussion

Industry Sector: Research

2:20-2:35 Malcolm McLeod (Landcare Research)

2:35-2:40 Louise Weaver (ESR)

Industry Sector: Public Health

2:40-2:55 John Whitmore (ADHB)

2:55-3:05 Questions/Discussion

3:05-3:25 Afternoon Tea

Water Industry Regulatory Reform

3.25 – 3.35 Noel Roberts (WaterNZ)

3.35 - 3.45 Questions/Discussion

Identification of Key Issues – Group Discussion

3:45-4:15 Sandy Ormiston/Trisha Simonson/Bronwyn Humphries

Closing Comments/Way Forward

4:15-4:30 Sandy Ormiston

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Department of Conservation: Wastewater Management on a Great Walk

Great Walks provide an iconic wilderness experience in New Zealand

and attract hundreds of thousands of visitors each year. Huts pro-

vide accommodation for visitors who spend a day or more on a walk.

Many people visit as day trips. Wastewater management at huts and

elsewhere on walks provides special challenges. We outline some of

these.

Visitor numbers. There are 36 great walk huts, with hut bunk num-

bers varying from about 57 (Lake Mackenzie Hut on the Routeburn

Track) to less than 20. At some remote locations, the bunk number

is a reliable design occupancy. Other huts have day walk visitors,

and their numbers can be 10 times or more the bunk number. There

are also often campsites associated with the great walk huts. Bunk

booking is required for overnight visitors and records provide reliable

overnight visitor numbers and patterns. Day visits fluctuate depend-

ing on time of year, weather, condition of the track and media arti-

cles. Numbers are not necessarily predicable.

Physical environment. Great Walks are where nature is spectacular

or otherwise exceptional: steep mountains, dense forest, high tus-

sock lands, coastal bays. Some places have high rainfall, snow and

extreme weather events. Often the topography is steep, rocky, or

swampy, and soil cover is shallow. Access is by foot, helicopter or, in

some cases, boat.

Construction logistics: Construction at these remote sites requires

exacting coordination, flexibility and cooperation by all parties. Fick-

le weather patterns, unexpected obstacles and additional material

or skill needs can result in major disruptions or significant additional

cost. Construction is usually by a few contractors with experience in

remote locations and materials and contractors are generally flown

in. Helicopter costs can range from $100k to over $300k for a large

hut development.

Peter Carter (DOC) and John Cocks (JCL)

Devil’s Staircase Tongarira Crossing Mangatepopo Hut Toilet

Forest (left) and rocky terrain (right)

Operational logistics: Typically, huts have wardens during the

walking season. Their duties are multiple and include looking

after wastewater systems. Preferably, systems require minimal

day to day attention or specialist training to operate. Wastewater

discharge occurs over short periods, when walkers arrive at a hut

or prepare to leave early in the morning. A stable, robust and

reasonably simple treatment process that accommodates such

peaks is needed. Typically this is a septic tank type system with

gravity discharge, although some systems include pumping by

solar or petrol pumps. Sludge needs routine removal by helicop-

ter or boat. Regulations inhibit or prevent discharge at on-site.

On the southern great walks, the wastewater systems are decom-

missioned outside of the great walk season and vault toilets are

used.

Design: Given the above constraints, reliable design requires

demanding investigations and good visitor information. Second-

ary treatment and other advanced systems need regular operator

attention or training, which poses significant risks. Conventional

or innovative land application techniques or waste removal pro-

vides public health and environmental protection.

Toilet foundation construction Tongariro Crossing

Clockwise from top left: waste flyout, manual dosing,

old septic tank, septic tank pump out.

Left to right: Waste vault toilet, solar powered pumping, above

ground LPED

Materials delivery (left) and toilet delivery on the Tongariro

Crossing (right)

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The Darfield On-site Wastewater Management Story Rob Potts (Lowe Environmental Impact) Lee Burbery (ESR)

Darfield is a rural township in the Selwyn District, located to-

wards the top of the Canterbury Plains. It sits atop of an exten-

sive unconfined alluvial gravel aquifer that is the regions princi-

pal freshwater drinking water resource. The town holds the

ignominious title of being the septic-tank capital of New Zea-

land – the resident population is in excess of 2,000 and effec-

tively all households operate an on-site wastewater manage-

ment system (OWMS). Community and Public Health (CPH), and

Selwyn District Council (SDC) have long harboured concerns

regarding the sustainability of wastewater management prac-

ticed in the town and the hazard it presents to human health.

As a knock-on effect of the Christchurch earthquakes of 2011,

the town experienced rapid population growth that was not

forecast and which revived interest in assessment of the

wastewater management status. In 2014, the Ministry of

Health (MOH) commissioned a review of the hazard that the

current wastewater discharge practice in Darfield [and Kirwee]

poses to the underlying groundwater resource.

Key points from the report are (Burbery, 2014):

Darfield is the largest town in NZ with no centralised

wastewater management system.

Groundwater in the underlying aquifer is heavily utilised

as a freshwater resource, including serving as the main

source of [untreated] drinking water.

It is perceived that the almost 80 m thick vadose zone

underneath the town provides an effective buffer to

contamination of the groundwater from microbiological

contaminants discharged via OWMs. That said, within

the district, Escherichia coli has on occasion been de-

tected in groundwater sampled from wells screening

125 m below ground level. This suggests the aquifer is

not entirely immune from microbial contamination origi-

nating from land-based practices.

Nitrate is the primary groundwater contaminant of con-

cern associated with discharges from OWMS’s at Dar-

field. Nitrate concentrations in the treated effluent

plume beneath the township are conceived to be in the

order of 65 mg NO3-N/L.

Subsurface conditions are not conducive to any natural

attenuation of nitrate and dilution of any groundwater

pollution in the locality is limited owing to the proximity

to a geological boundary of the Canterbury Plains aqui-

fer system.

At the current housing density, nitrogen loadings from

the township to the groundwater resource are unlikely

to be much different from loadings from the surround-

ing agricultural land-use.

Key future issues for Darfield:

The benefits of a concentrated land application site with

high level treatment versus well-functioning and main-

tained multiple on-site discharges over a large area.

The Canterbury District Health Board conducted a sur-

vey of Darfield wastewater management systems in

2014 and found that many systems were poorly operat-

ed and maintained. More than 100 systems were sur-

veyed and found fewer than 10% of residents did regu-

lar service or maintenance. Many residents had poor

knowledge of their on-site systems and about a third

had not had their tank emptied in the last 5 years. Near-

ly 1 in 3 systems had some kind of failure. Survey Re-

port click here.

Key future issues for Darfield: continued

The older parts of Darfield are small sections with many

of the OWMS discharging via gravity seepage to

soakholes, as under the Transitional Regional Plan

(TRP), soak pits in Darfield were a permitted activity

provided certain conditions were met. Under the LWRP

these can continue to be used as long as they were

lawfully established prior to 1 November 2013 and

provided there have been no changes to the system or

increases in volumes discharged.

Darfield has an older than normal demographic, with

many farmers retiring to the area. In addition, due to its

distance from Christchurch, it is also seen as a less

expensive housing area. This means that there is less

enthusiasm for a reticulated system, with many

vehemently opposed to having to spend another

$25,000 per household for a scheme. However, at the

same time, many see the lack of the community sewer-

age system as holding back development of Darfield.

Subdivisions are still occurring, with section sizes

ranging from 450 m2 to 0.5 ha. Their OWMS are costing

between $10,000 and $25,000.

Stantec (2016) have undertaken a high level option assess-

ment for Darfield. Levels of treatment assessed were:

1) High Tech – Activated sludge plant (ASP) with Biological Nutrient Removal (BNR);

2) Medium Tech – lowly loaded Trickling Filter (TF) plant; and

3) Low Tech – Waste stabilisation Pond (WSP) or oxidation pond.

Each of the above methods has different amounts of N removal

which results in different amounts of area being required to

apply the effluent to land ranging from 21 ha to 90 ha. Capital

costs for reticulation and the treatment plant are in the order of

$19,000 – 25,000/lot based on 2041 population estimates. A

possible option is to just connect the central business part of

the town (includes 2 hotels, 2 cafes and a bakery and a butch-

er) and the older and smaller sections to get a scheme started.

The recommendation that was put forward was Option 3, the

waste stabilisation pond for the treatment facility. This is due to

the following advantages:

Lowest capital cost/investment – WWTP;

Lowest NPV (excluding consideration of land that is already owned);

Ability to stage development; and

Lowest operating cost (operator input/energy costs).

Lee

Rob

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The Darfield On-site Wastewater Management Story - continued

The network options to convey the wastewater to the WWTP

considered were:

1) Gravity sewer – decommission septic tanks, direct con-

nection to gravity sewer reticulation;

2) Low pressure sewer system – decommission septic

tanks, install new pump pot, connect to pressure reticu-

lation;

3) STEP system – reline septic tank, install new pump pot,

connection effluent sewer reticulation;

4) Vacuum sewer system – decommission septic tank,

gravity connection to pot in berm, connection to vacuum

reticulation.

The option that was recommended was Option 2, the low-

pressure sewer system. This is the preferential option due to

the benefits listed below:

Over-riding factor of seismic resilience;

Lower ongoing operation and maintenance costs com-

pared to vacuum systems;

Flexibility associated with alignment and installation

depth; and

Fewer constraints for future connections.

Nitrogen Leaching Assessment:

Loe (2013) provided the technical s32 report to support setting

nitrogen loading (leaching) limits in the Canterbury Regional

Council’s Land and Water Regional Plan (LWRP). He used 9 kg

loading per primary treatment system (septic tank) and 3 kg

per secondary treatment system and assumed all new builds

post 2006 were secondary – this gave 56 t N/yr in the Selwyn

Waihora Zone. Within Darfield, pre-2006 was approximately

1,100 people and post-2006 an additional 2,000 people. At

2.5 people/household, this equates to 440 houses pre and

another 800 post-2006

The assumptions in the Loe report regarding secondary sys-

tems post 2006 is not correct, with many primary systems still

being installed with LPED discharge systems. For the purposes

of this assessment, it is assumed that 50% following 2006 are

secondary with SDI and 50% primary and LPED.

Basic Calculation: 3000 people at 2.5 per house and 200 L/p/

d is 500 L/d/household. Nitrogen following a primary system is

in order of 50 mg/L with say no reduction in the LPED system,

and secondary systems nitrogen in the order of 30 mg/L with

reduction in the SDI land treatment area due to plant uptake,

microbe use and denitrification of say 30%. Therefore a prima-

ry system leaches approximately 9 kg N/yr/household (same

as Loe calculation), and the secondary system 4 kg N/yr/

household. This equates to 9,160 kg N/yr into the aquifer sys-

tem from Darfield’s on-site systems.

So how does this compare to agriculture? The LWRP allows 15

kg N/ha/yr from farming in this nutrient sensitive zone, so

9,160 kg N/yr is equivalent to 610 ha of allowable farming.

Also, how different would it be if there was a community

scheme?

And how different would it be if there was a community

scheme. Selwyn District Council has a 142 ha block of land on

the south-eastern side of Darfield that was purchased specifi-

cally for a future sewage scheme – this is a great start (Figure

1). Assuming a wastewater treatment plant producing 30 mg/

L nitrogen, irrigating to the SDC land with a cut and carry

landuse, then the 9,160 kg N/yr leaching would be reduced to

around 1,300 kg N/yr leached, based on N loading being

matched to N removed in herbage but winter drainage still re-

sulting in leaching. Equates to 90 ha of allowable farming.

However, the main advantage of a community scheme from an

environmental risk point of view is the centralised operation

and management, with on-going maintenance, as well as moni-

toring performance and the environment.

What Does the Future Hold?

Kicking off a community scheme did not make Selwyn District

Council’s LTP, so the earliest that a Council promoted scheme

may occur would be 2034.

A private plan change has been lodged with Council that has

over 100 sections and an Aged Care Facility in Stage 1 and

another 900 lots in a future deferred zone. This was not con-

sidered favourably by the Health Board and they opposed it.

Fortunately the developer is forward thinking and has proposed

a full reticulated system and a community WWTP system and

LTA for their development. Unfortunately this is on the oppo-

site side of Darfield to the Council site, so the developer has

set aside an additional 6 ha site for treatment and land treat-

ment, along with a short term consent that will hopefully kick

start a community scheme for all or at least the core commer-

cial areas of Darfield and future development.

Figure 1: SDC Owned Farm for Sewage Scheme

Figure 2: Darfield business zones, existing B1 zone (green) and ex-

panded B1 zone (yellow)

References:

Burbery, L. (2014). The potential hazard on-site wastewater

treatment systems in Darfield and Kirwee present to local

groundwater quality and critique of current assessment meth-

ods. Prepared as part of a Ministry of Health contract for sci-

entific services. Client report FW 14004. Christchurch: Insti-

tute of Environmental Science and Research Limited.

Loe, B, February 2013. Selwyn- Waihora Catchment. Estimat-

ing nitrogen and phosphorus contributions to water from dis-

charges of sewage effluent, from community systems, and

milk processing wastewater. Environment Canterbury Report

No, R13/8.

Stantec, March 2016. Darfield Wastewater Strategy. Pre-

pared for Selwyn District Council.

[email protected]

[email protected]

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Managing stormwater on land to protect surface water

Robyn Simcock - Manaaki Whenua Landcare Research

Stormwater is a valuable resource, but can also degrade

surface waters, especially when it collects contaminants,

and cause erosion or flooding. At the 2018 NZLTC con-

ference in Rotorua Brian Levine (NZLTC Student Scholar-

ship recipient) reported promising results from the Phos-

phorus Mitigation Project. A detainment bund that

trapped stormwater runoff from high-producing pasture

for 3 days before being released, greatly reduced P, N

and sediment. Variations on this method of protecting

waterways by slowing, detaining, infiltrating and evapo-

rating runoff have been used in cities and roadsides;

engineered swales, bioswales and raingardens have pro-

liferated throughout New Zealand since ‘TP10’ (2003)

and ‘TP124’ (2000) were produced by Auckland Regional

Council to guide management of stormwater runoff.

These technologies are a core part of ‘Water Sensi-

tive’ (Urban), ‘Low Impact’ or ‘Sustainable’ Urban Design

(acronyms WSUD, LID or SUDs).

Experience in our cities over the last 20 years has helped

design and integrate these stormwater treatment devic-

es in ways that deliver more value for money and cost

less to maintain. These technologies are still not yet

mainstream in New Zealand. However, the National Poli-

cy Statement for Freshwater Management is likely to be

a key driver, especially as passing storm water through

plants and soil aligns closely with kaitiaki values and

complements design through a te ao Māori lens.

Last year, New Zealand and international learning was

summarised in a series of free, web-based resources on

the “Activating Water Sensitive Urban Design’ website,

funded by the ‘Building Better Homes, Towns and Cities

National Science Challenge. They can be accessed here

link. The resources include:

Case studies and ‘WSUD walks’ in Auckland,

Christchurch and Queenstown lakes

Understanding costs and maintenance

Assessing the full benefits, and ‘More than Water’

assessment tool

Te Ao Māori and WSUD

Incentives and funding

Unlike pipes and other ‘hard infrastructure’ WSUD can

help celebrate stormwater and enhance receiving waters

and where we live, not just treat or dispose stormwater.

Both rural and urban areas have many opportunities to

better manage stormwater, and these resources should

help.

From left to right: raingardens Wynyard Quarter (Auckland); mown swale with trees in Stoke; no-mow swale in

Manurewa Botanic Gardens; roadside raingarden in central Christchurch

[email protected]

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NZLTC Resources

The NZLTC is a member of Northwest Biosolids (University of Washington). Northwest Biosolids provide its members with

exclusive access to up-to-date biosolids research and online resources. These resources are available on the NZLTC members

only portal as a mix of abstracts and full papers. https://nzltc.wordpress.com/members-area/northwest-biosolids-resources/

The latest Northwest Biosolids December and January library focus is on:

- Cannabis

- N2O (Nitrous oxide)

If you are a member and have forgotten the members only password or would like more information about becoming an

NZLTC member to gain access to these resources please contact the NZLTC Technical Manager

[email protected]

https://nwbiosolids.org/

Title: Legal cannabis laws, home cultivation, and use of edible cannabis products: a growing relationship?

Author: Borodovsky, J.T. and A.J. Budney

Source: International J. Drug Policy 2017 50: 102-110

Title: The quasi-legal challenge: assessing and governing the environmental impacts of cannabis cultivation in the North

Coastal Basin of California

Author: Short Gianotti, A.G., J. Harrower, G. Baird, S. Sepaniak

Source: Land Use Policy 2017 61: 126-134

Title: The carbon footprint of indoor cannabis production

Author: Mills, E.

Source: J. Environ. Qual. 2003 32: 100-108

Title: The benefits of growing cannabis with compost

Author: Samuelson, P

Source: Cannabistraininguniversity.com 2019

Title: The genesis of a critical environmental concern: Cannabinoids in our water systems

Author: Saleh, N.B., O. Apul, T. Karanfil

Source: Environ. Sci. Tech. 2019 53: 1746-1747

Approximately 192 million people worldwide aged 15−64 (i.e., 3.9% of the global population, per 2016 estimates) regu-

larly use Cannabis, more commonly known as marijuana. The estimated market share of this widely used drug will sur-

pass $22 billion by 2022. On June 28, 2018, the United States Food and Drug Administration approved Epidiolex, a can-

nabinoid-based drug developed for the treatment of a rare form of epilepsy. Unfortunately, despite their widespread avail-

ability, un- certainty-in-point and mass production projections, adverse effects on the nervous system and increased

pharmaceutical use, cannabinoids remain the most understudied class of ECs within aquatic systems. The transfor-

mation of these products, which are often more toxic than the parent compounds, encourages understanding the reac-

tion processes that cause their development. Indeed, new organic contaminants or ECs that are created by the transfor-

mation processes in water and wastewater systems have been detected in waste and surface waters, which means that

treatment processes must evolve accordingly. Halogenated methanesulfonic acid (HMAs), a new class of organic mi-

cropollutant produced from an approved drug, is now prevalent in the water cycle and is one of the latest addition to the

EC list. As with HMAs, cannabinoids will likely introduce similar compounds during their passage through engineered

treatment systems.

Cannabis

Page 11: Issue 64 Newsletter Feb 2020 NZ Land Treatment Collective ...wastes and land applied livestock manure as related to pathogen contamination of groundwater and human health risks. His

NZLTC Technical Manager

Bronwyn Humphries

[email protected]

[email protected]

NZLTC Finance and Administration Management

Robyn Chapple

[email protected]

11

NZLTC Contacts

Important dates

2019/2020 NZLTC Memberships due

NZLTC Conference abstracts close 21st Feb

SWANS-SIG / NZLTC Workshop 30 March

Palmerston North

NZLTC Conference 31 March - 2 April

Palmerston North

NZLTC AGM 2 April 2020 Palmerston North

NZLTC Technical Reviews -

members only

In the next few months two NZLTC technical review

documents will be made freely available to our

members only. The topics are:

Managing disease outbreaks and the

implications for land treatment: focus on

Mycoplasma bovis

Microplastics in New Zealand Waste Water

Treatment Plants (WWTPs) and the implications

for land treatment If you wish to become an NZLTC member to gain access

to these documents please contact Bronwyn

Humphries.

Title: Global nitrous oxide emission factors from agricultural soils after addition of organic amendments: a meta-analysis

Author: Charles, A., P. Rochette, J.K. Whalen, D.A. Angers, M.H, Chantigny and N. Bertrand

Source: Ag. Ecosys. Environ. 2017 236:88-98

Title: Nitrous oxide emissions respond differently to mineral and organic nitrogen sources in contrasting soil types

Author: Pelster, D.E., M.H. Chantigny, P. Rochette, D.A. Angers, C. Rieux and A. Vanasse

Source: J. Environ. Qual. 2012 41: 427-435

Title: Effects of organic and inorganic fertilizers on greenhouse gas (GHG) emissions in tropical forestry

Author: de Urzedo, D.O., M.P. Ranco, L.M. Pitombo, and J. Braga do Carmo

Source: Forest Ecol. Manage 2013 310: 37-44

Title: Soil nitrous oxide emissions from agricultural soils in Canada: Exploring relationships with soil, crop and climate

variables

Author: Rochette, P., C. Liang, D. Pelster, O. Bergeron, R. Lemke, R. Kroebel, D. MacDonald, W. Yan, C. Flemming

Source: Agric. Ecosys. Environ. 2018 254: 69-81

National scale emissions of nitrous oxide (N2O) from agricultural soils are often estimated using a unique fer- tilizer-

induced emission factor (EF); thereby neglecting how factors other than nitrogen input could impact emissions. In the

present study, we compiled soil N2O flux data collected since 1990 on agricultural soils in Canada, to identify key soil

and climate factors, and management practices that explain variations in N2O emissions and in EF. Stepwise regression

analysis showed that the growing season precipitation was the most important factor impacting N2O emissions, and that

cumulative N2O fluxes and EFs could be predicted using equations (R2 from 0.68 to 0.85) including two to five of the

following variables: growing season precipitation, ratio of growing season precipitation to potential evapotranspiration,

mean annual air temperature, crop type (annual or perennial), soil pH, texture and organic carbon content. We conclude

that N2O EFs could be effectively stratified based on growing season precipitation, soil texture (coarse, medium and fi-

ne), type of N (synthetic and organic), and crop type (perennial and annual). We propose EFs that account for the domi-

nant factors that modulate the nitrogen fertilizer-induced emissions and should improve regional and national estimates

in Canada. They may also provide useful information for guiding the development of soil N2O emission quantification in

other countries.

Title: Nitrous oxide emissions from clayey soils amended with paper sludge and biosolids of separated pig slurry

Author: Chantigny, M.H., D.E. Pelster, M.H. Perron, P. Rochette, D.A. Angers, L.E. Parent, D. Masse, and N. Ziadi

Source: J. Environ. Qual. 2013 42:30-39

N2O - Nitrous oxide