3 Waste Volumes

This section analyses total waste flows in New Zealand as used in analysis.

3.1 Waste flows to landfill

The amount of waste flow to landfill has been estimated using data in the 2002 Landfill Review and Audit published by MfE.12 This document contains data on annual landfill tonnage, by region, for 2001/2002. These quantities are then updated by applying regional population growth factors (Stats NZ), to obtain an estimate of approximately 3.25 million tonnes of waste being disposed to landfill in 2006 (Table 1).13

Table 1: Annual waste to landfill by region (2002)

 

2002

2006 (estimated)

Auckland

930,000

1,082,802

Bay of Plenty

151,000

158,535

Canterbury

340,000

359,794

Hawkes Bay/Gisborne

140,000

140,140

Manawatu/Wanganui

163,000

162,266

Nelson/Tasman/Marlborough

106,000

113,057

Northland

98,000

100,772

Otago

162,000

168,577

Southland

109,000

107,802

Taranaki

60,000

59,760

Waikato

237,000

246,133

Wellington

501,000

522,368

West Coast

25,000

24,825

Total

3,022,000

3,246,831

Source: Ministry for the Environment (2003) 2002 Landfill Review and Audit; Covec estimates.

These regional estimates of waste tonnage to landfill are then disaggregated further to a TA level. The allocation is based on population estimates. In certain cases, where a TA straddles multiple regions, the waste estimate is allocated on the basis of the population of the TA contained within a specific region.

Estimates of the composition of waste to landfill are derived from surveys of disposal facilities reported by WasteNot Consulting (Table 2). We have applied these proportions to our estimated tonnage to obtain estimates for the tonnage of specific waste products going to landfills in 2006.

Table 2: Composition of waste to landfill

Primary category

% of total

Paper

14.9%

Plastics

9.1%

Putrescibles

23.3%

Ferrous metals

5.1%

Non-ferrous metals

0.9%

Glass

2.5%

Textiles

3.9%

Nappies and sanitary

2.7%

Rubble, concrete

12.2%

Timber

13.9%

Rubber

1.0%

Potentially hazardous

10.5%

Total

100%

Source: WasteNot Consulting (2006) Waste composition and construction waste data. Prepared for the Ministry for the Environment.

3.2 Waste recycled

The annual tonnage of diverted waste is estimated by combining data on household recycling with data on business recycling.

The annual tonnage of household waste that is diverted is estimated from the data in the NZWS Targets TA Survey. The data in this survey includes estimates by the TAs of the amount of inorganic and organic waste diverted by them. The inorganic waste collected is then further broken down into separate waste product streams (Table 3).

Table 3: Proportion of waste products in diverted inorganic waste

Paper

Plastics

Ferrous metals

Non-ferrous metals

Glass

60.0%

9.0%

3.7%

1.0%

26.2%

Source: New Zealand Packaging Accord 2005 Progress Report.

The NZWS Targets TA Survey also contains data provided by the TAs about the amount of organic waste diverted. We use these data in our organic waste analysis. Using this approach, the estimates of household waste diverted are shown in Table 4.

Table 4: Household recyclable material quantities

 

Generated (tonnes)

Recovered (tonnes)

Recovered (%)

Paper

299,625

200,893

67%

Plastic

42,303

30,114

71%

Metal

31,029

15,793

51%

Glass

127,841

71,069

56%

Organic

415,764

195,620

47%

Total – recyclables

916,563

513,489

56%

We have estimated the amount of annual diverted business waste from data provided by MfE for total waste diverted (Table 5) and subtracting the estimates of household waste diverted as calculated above. The resulting estimates of business waste diverted are shown in Table 6.

The difference between the above numbers and the estimated amount of diverted household waste (from the NZWS survey) for a specific product is then allocated to the TAs according to population.

Table 5: MfE’s best estimate of materials diverted from landfill and cleanfill

Waste stream

Amount diverted (estimated tonnes)

Data source

Glass

92,826

Packaging Accord Data 2005

Paper

454,212

New Zealand Paper and Packaging Association estimate for 2005

Plastics

39,100

Plastics New Zealand estimates for 2005

Scrap metal

495,000–550,000

Scrap Metal Recycling Association annual estimates

Organics

312,085

Survey of TAs 2006

Construction and demolition

1,000,000

Estimates from direct contact with construction and demolition industry

Source: Ministry for the Environment

Table 6: Commercial recyclable material quantities

 

Generated (tonnes)

Recovered (tonnes)

Recovered (%)

Paper

493,912

254,000

51%

Plastic

203,634

9,000

4%

Metal

621,130

500,000

80%

Glass

50,236

17,767

35%

Organic

501,530

116,465

23%

Total – recyclables

1,870,443

897,232

48%

3.3 Landfills

In 2002 there were an estimated 155 landfills accepting approximately three million tonnes of waste, but it is estimated that only 43 will remain by 2010 (Table 7). In 2002 only 20 per cent had engineered containment whereas this was expected to increase to 67 per cent of landfills by 2010. In 2002 only 83 per cent of landfills measured the quantity of waste and 82 per cent charged for it; these figures are expected to increase to 100 per cent by 2010.14

With a reduction in the number of landfills, they are increasing in size. Approximately three million tonnes of waste going to 115 landfills (2002 data) results in an average rate of disposal of 26,000 tonnes. However recently-opened landfills include Hampton Downs, south east of Auckland that accepts 200,000 tonnes per year and Kate Valley near Christchurch, opened in 2005, that will take 300,000 tonnes per year.

Table 7: Total landfills

Location 2001/02 2005 2010
Number Tonnes/year Number Number Number high standard

Auckland

6

930,000

3

3

1

Bay of Plenty

7

151,000

3

2

1

Canterbury

9

340,000

2

3

1

Hawke’s Bay/Gisborne

4

140,000

3

5

1

Manawatu/Wanganui

13

163,000

10

4

1

Northland

4

98,000

4

2

1

Otago

13

162,000

11

6

0

Southland

13

109,000

13

1

1

Nelson/Tasman/Marlborough

4

106,000

4

3

0

Taranaki

6

60,000

2

1

1

Waikato

6

237,000

6

5

2

West Coast

20

25,000

8

4

0

Wellington

10

501,000

9

4

1

New Zealand

115

3,022,000

78

43

11

Source: Ministry for the Environment (2003) 2002 Landfill Review and Audit.

For analysis, we have made assumptions both about the size and location of landfills so that transport costs can be estimated also (see Annex 1). The basis for the analysis is the 2010 projections of 43 landfills in total and the regional location of these. This was used to define the location of individual landfills and was combined with waste generation data to define the size of these landfills and thus their costs (see Section 4.3).

12 Ministry for the Environment (2003) 2002 Landfill Review and Audit.

13 Currently unpublished landfill census data for 2006 estimate total waste going to landfill as 3.156 million tonnes in 2006.

14 Ministry for the Environment (2003) 2002 Landfill Review and Audit.