South East Queensland
11.4 Wastewater collected

Supporting Information

This line item consists of the wastewater collected by the wastewater collection system within the South East Queensland (SEQ) region. As data were not available for line item 11.7 Stormwater ingress and line item 11.8 Infiltration from groundwater and the only data available for this line item was wastewater treatment plant (WWTP) inflow, this line item actually represents WWTP inflow as a proxy for wastewater collected. The overestimation for this line item is offset by the under estimation for line item 11.7 Stormwater ingress and line item 11.8 Infiltration from groundwater.

Wastewater treatment plant inflow by urban utility
Urban utility Wastewater treatment plant (WWTP)  Volume
(ML) 
AllConnex Water Beenleigh               5,653
Capalaba               2,192
Cleveland               3,193
Coombabah             26,437
Elanora             10,005
Flagstone                  111
Jimboomba                   87
Logan Village                   20
Loganholme             20,234
Merrimac             14,027
Mount Cotton                  337
Pimpama               2,519
Thorneside               3,300
Victoria Point               3,065
Total AllConnex             91,180
Queensland Urban Utilities Aratula                   19
Beaudesert                  541
Boonah                  213
Bundamba               7,109
Canungra                   68
Carole Park               1,573
Esk Shire                   99
Fairfield               1,324
Fernvale                  100
Forest Hill                   46
Gatton Shire                  723
Gibson Island             20,688
Goodna               5,147
Helidon                   60
Kalbar                   49
Karana Downs                  164
Kilcoy Shire                  177
Kooralbyn                   60
Laidley Shire                  351
Lowood                  156
Luggage Point             66,636
Nudgee                   59
Oxley             26,745
Rosewood                  173
Sandgate             10,248
Toogoolawah                   98
Wacol               2,138
Wynnum               4,419
Total Queensland Urban Utilities           149,183
Unitywater Brendale               3,027
Burpengary East               3,387
Caboolture               5,586
Dayboro                   74
Landsborough                  937
Murrumba Downs               8,792
Redcliffe               6,862
Woodford                  186
Total Unitywater             28,851
Total SEQ region           269,214

Quantification Approach

Data Source

Unity water daily WWTP inflow data. AllConnex Water and Queensland Urban Utilities annual WWTP inflow data.

Provided by

Bureau of Meteorology.

Method

Most of the individual discharges into the wastewater collection system are not metered and data on trade waste discharges were not available. Metered data for inflow into the WWTPs were available and  were used to populate this line item. If data for line item 11.7 Stormwater ingress and line item 11.8 Infiltration from groundwater from groundwater were available, this would have been removed from the WWTP data to estimate wastewater collected by the wastewater collection system. As data were not available for these line items, the wastewater collected was assumed to be the entire WWTP inflows.

Assumptions, Limitations, Caveats and Approximations

Including all WWTP inflow in this line item has resulted in an overestimation of wastewater collection, expected to be in the order of around 20–60%. The overestimation for this line item is offset by the underestimation for line item 11.7 Stormwater ingress and line item 11.8 Infiltration from groundwater. With the development of methods for calculating stormwater ingress and groundwater infiltration, the WWTP inflow represented in this line item in the 2011 Account may be split across line item 11.4 Wastewater collected, line item 11.7 Stormwater ingress and line item 11.8 Infiltration from groundwater in future accounts.

Uncertainty Information

The uncertainty estimate was not quantified.

Comparative year

This line item was not included in the 2010 Account as retail customers of the urban water system were considered to be part of the urban water system. The supply of urban water to, and collection of wastewater from, these retail customers was considered to be a within store flow and was not included in the 2010 Account water accounting statements.

Wastewater collected was included in the Urban water region note of the 2010 Account. The volume reported in this note of 212,085 ML has been included in the 2011 Account as the comparative year volume for this line item.