Melbourne Water
Social and Environment Data
2005 / 2006

Back

Eastern Treatment Plant inputs and discharges

Raw sewage monitoring

The quality of raw sewage entering the plant is described in the following table. (All data in mg/L unless otherwise indicated). The data results are higher than last year because sludge was drained from the primary sedimentation tanks to the head of the plant to prevent excessive sludge accumulating in the tanks.

Parameter, Units Median 90th Percentile Maximum
BOD5 (mg/L) 465 610 940
Suspended Solids (mg/L) 545 1000 2000
PH (pH units) 7.1 7.3 7.6
Ammonia as N (mg/L) 37 41 45
Total Combined Nitrogen (mg/L) 68.5 85 120
Total Phosphorus (mg/L) 16.5 21 30
Anionic Surfactants MBAS (mg/L) 5 7 12
Cadmium (mg/L) 0.0007 0.0018 0.0052
Chromium (mg/L) 0.033 0.06 0.065
Copper (mg/L) 0.16 0.25 0.44
Lead (mg/L) 0.0115 0.019 0.027
Mercury (mg/L) 0.00021 0.00051 0.00081
Phenol (µg/L) 51 24.81 301
Toluene (µg/L) 2.51 5.91 151
Benzene (µg/L) 0.51 0.51 121
PAH's total (µg/L) 41,2 41,2 41,2

Notes to Table:
1 1/2 Limit of Detection Values used. All results found to be less than the detection limits were taken as half the given value i.e. <2 = 1.
2 Total PAH's are calculated using the sum of the following PAH's:
(acenapthylene, anthracene, 1,2-benzanthracene, 3,4-benzofluoranthene, benzo (k) fluoranthene, 1,12-benzoperylene, benzo(a) pyrene, chrysene, dibenzo(a.h)anthracene, fluorene and indeno(1.2.3-cd)pyrene. All results were less than the detection limit and were calculated at half the given value i.e. <2 = 1).

Top of page

Discharge to water

The following results represent samples taken from the final effluent sample point at Trueman’s Rd and flow measurements at the Eastern Treatment Plant from 1 July 2004 to 30 June 2005. (All data in mg/L unless otherwise indicated)

Parameter, Units Median 90th Percentile Maximum
Licence Limit Result Licence Limit Result Licence Limit Result
BOD5 NS 26 NS 43 NS 70
CBOD5 20 5 40 8 NS 16
Suspended Solids 30 12 60 25 NS 39
pH (pH units) NS 7.4 NS 7.8 6 - 9 8
Ammonia as N 30 13 NS 29 40 34
Total Combined Nitrogen NS 26 NS 33 NS 36
Total Phosphorus NS 6.1 15 8.4 NS 9.8
Anionic Surfactants 0.4 0.1 0.7 0.2 NS 1
Cadmium 1 NS 0.0001 0.005 0.0001 0.01 0.0001
Chromium NS 0.004 0.075 0.006 0.15 0.007
Copper NS 0.0115 0.05 0.014 0.1 0.002
Lead 1 NS 0.0005 0.05 0.002 0.1 0.002
Mercury 1 NS 0.00005 0.0005 0.00005 0.001 0.0001
Phenol (µg/L) NS 0.5 NS 0.5 100 0.5
Toluene (µg/L) NS 0.5 NS 0.5 50 1
Benzene (µg/L) NS 0.5 NS 0.5 25 0.5
PAH's total (µg/L)2 NS 4 NS 4 15 4
ETP Discharge (ML/day)3 NS 375 NS 417 NS 553
Outfall Discharge (ML/day)4 540 379 NS 433 NS 575
Total Residual Chlorine (mg/L) NS 0.04 NS 0.06 1 0.13
E.coli (orgs/100mL) 200 16 1000 93 NS 3100
Enterococci (orgs/100ml) NS 10 NS 89 NS 320
Dissolved Oxygen NS 7 NS 7.6 >6.0 6.0-7.9

Notes to Table:
1 All results found to be less than the detection limits were taken as half the limit of detection (LOD) i.e. <8 = 5.
2 Total Poly Aromatic Hydrocarbons (PAH’s) are calculated using the sum of the following PAH’s: (acenapthylene, anthracene, 1,2-benzanthracene, 3,4-benzofluoranthene, benzo(k)fluoranthene, 1,12-benzoperylene, benzo(a)pyrene, chrysene, dibenzo(a.h)anthracene, fluorene and indeno(1.2.3-cd)pyrene.
3 ETP outflow flow excluding South East Water treatment plants that also discharge treated effluent into the South East Outfall.
4 Calculated Total Outfall flow is the actual flow to the Outfall including South East Water discharges to the South East Outfall.
NS = No Specified Limit.

Top of page

Discharge to land

The following results detail the quality of effluent discharged to land at the Eastern Treatment Plant (for irrigation purposes) as sampled from the final effluent sample point and the Eastern Treatment Plant reuse sample point from 1 July 2005 to 30 June 2006.

Parameter, Units Unit Median 90th Percentile
E.coli1 Org/100mL 20 148
Electrical Conductivity2 µS/cm 900 1000
BOD52 mg/L 35 63
CBOD52 mg/L 5 7

1 Sample taken from the reuse sample point
2 Sample taken from the final effluent sample point

Top of page

Effluent flow to the outfall

Daily and monthly median and maximum flows (ML/day) were measured during 2005/06. Monthly median and maximums are shown below. The total outfall flows for 2005/06 are as follows:

Description Flow (ML) Comment
ETP Outflow 132,335 Total outfall pump station flow minus internal plant use
Calculated Outfall flow 135,122 Boags Rocks Outfall flow (ETP + South East Water treatment plant flows - water recycling)

 

Month Median (ML) Maximum (ML)
July 2005 334 414
August 2005 372 427
September 2005 410 550
October 2005 390 424
November 2005 392 509
December 2005 386 553
January 2006 317 418
February 2006 340 416
March 2006 365 412
April 2006 402 418
May 2006 377 444
June 2006 343 423

Top of page

Bacteriological monitoring - beach samples

Samples of receiving waters were taken throughout the year at six locations along the Gunnamatta and St Andrews beaches as detailed below:

The results are presented as a rolling 30-day median and rolling 60-day 75th percentile as per the recreational water quality guidelines given in the State Environment Protection Policy Waters of Victoria. The day results for E.coli and Enterococci for all samples taken at all the above sample points were consistent with the Policy requirements throughout the year. The results are as follows:

E.coli (orgs / 100 ml)

Date Beach 1 Beach 2 Beach 3 Beach 4 Beach 5 Beach 6
Day
reslt		 30
Day
Mdn*		 Day
reslt		 30
Day
Mdn*		 Day
reslt		 30
Day
Mdn*		 Day
reslt		 30
Day
Mdn*		 Day
reslt		 30
Day
Mdn*		 Day
reslt		 30
Day
Mdn*
4-Jul-05 2 0 0 0 2 2
12-Jul-05 18 0 0 0 12 2
20-Jul-05 0 0 0 0 7 0
25-Jul-05 2 2 0 0 4 0
28-Jul-05 2 2 0 0 0 0 0 0 0 4 0 0
5-Aug-05 4 2 0 0 0 0 0 0 4 4 0 0
11-Aug-05 0 2 0 0 0 0 0 0 6 4 0 0
17-Aug-05 0 2 0 0 0 0 0 0 4 4 0 0
23-Aug-05 0 0 0 0 0 0 0 0 14 4 2 0
29-Aug-05 2 0 0 0 0 0 0 0 0 4 0 0
5-Sep-05 2 0 0 0 0 0 0 0 2 4 0 0
13-Sep-05 0 0 0 0 0 0 0 0 11 4 2 0
21-Sep-05 0 0 0 0 0 0 0 0 0 2 0 0
26-Sep-05 0 0 0 0 0 0 0 0 0 0 0 0
29-Sep-05 8 0 2 0 0 0 2 0 0 0 0 0
7-Oct-05 0 0 0 0 0 0 0 0 2 0 2 0
13-Oct-05 0 0 0 0 0 0 0 0 0 0 0 0
19-Oct-05 52 0 0 0 0 0 0 0 36 0 0 0
25-Oct-05 12 8 0 0 4 0 0 0 0 0 0 0
31-Oct-05 0 0 0 0 0 0 0 0 14 2 4 0
2-Nov-05 10 10 0 0 0 0 0 0 0 0 0 0
9-Nov-05 4 10 0 0 2 0 0 0 42 14 12 0
17-Nov-05 0 4 0 0 4 2 0 0 32 14 0 0
21-Nov-05 4 4 0 0 0 0 0 0 22 22 0 0
25-Nov-05 0 4 0 0 0 0 0 0 6 22 0 0
1-Dec-05 6 4 0 0 0 0 0 0 55 32 0 0
7-Dec-05 10 4 0 0 0 0 2 0 58 32 2 0
13-Dec-05 10 6 0 0 0 0 0 0 6 22 2 0
19-Dec-05 6 6 0 0 0 0 0 0 5 6 0 0
28-Dec-05 78 10 8 0 0 0 2 0 84 55 0 0
3-Jan-06 3 10 4 0 0 0 0 0 44 44 0 0
11-Jan-06 0 6 0 0 0 0 0 0 28 28 0 0
16-Jan-06 4 4 0 0 0 0 0 0 240 44 0 0
19-Jan-06 10 4 0 0 0 0 0 0 18 44 0 0
27-Jan-06 14 4 0 0 0 0 0 0 48 44 6 0
2-Feb-06 6 6 0 0 2 0 0 0 40 40 0 0
8-Feb-06 2 6 0 0 0 0 0 0 8 40 0 0
14-Feb-06 0 6 2 0 0 0 0 0 22 22 0 0
20-Feb-06 8 6 0 0 4 0 0 0 38 38 2 0
27-Feb-06 4 4 0 0 2 2 0 0 30 30 0 0
6-Mar-06 120 4 0 0 4 2 4 0 58 30 0 0
14-Mar-06 18 8 8 0 12 4 10 0 44 38 14 0
22-Mar-06 190 18 0 0 0 4 0 0 63 44 6 2
27-Mar-06 0 18 0 0 0 2 0 0 130 58 2 2
30-Mar-06 49 49 22 0 20 4 68 4 360 63 4 4
5-Apr-06 2 18 2 2 0 0 0 0 15 63 0 4
11-Apr-06 10 10 0 0 0 0 0 0 7 63 0 2
18-Apr-06 15 10 0 0 0 0 0 0 18 18 0 0
20-Apr-06 12 12 6 2 0 0 2 0 27 18 2 0
24-Apr-06 20 12 0 0 0 0 0 0 18 18 0 0
1-May-06 28 15 0 0 0 0 0 0 8 18 0 0
9-May-06 12 15 0 0 0 0 0 0 2 18 0 0
17-May-06 26 20 2 0 0 0 0 0 16 16 0 0
22-May-06 4 20 0 0 0 0 0 0 0 8 0 0
25-May-06 2 12 2 0 0 0 4 0 0 2 0 0
1-Jun-06 400 12 0 0 0 0 0 0 8 2 0 0
7-Jun-06 0 4 0 0 0 0 2 0 4 4 0 0
13-Jun-06 4 4 0 0 0 0 0 0 0 0 2 0
19-Jun-06 3 3 2 0 0 0 0 0 8 4 0 0
26-Jun-06 2 3 0 0 0 0 0 0 6 6 0 0

*Median. State Environmental Protection Policy (SEPP), Waters of Victoria specifies for primary contact recreational activities a rolling 30 d median less than 150 orgs/100 ml

Enterococci (orgs/100 ml)

Date Beach 1 Beach 2 Beach 3
Day Result 30 Day Median* 75th Perce-
ntile **		 Day Result 30 Day Median* 75th Perce-
ntile **		 Day Result 30 Day Median* 75th Perce-
ntile **
4-Jul-05 2 0 6
12-Jul-05 4 0 0
20-Jul-05 0 0 2
25-Jul-05 0 0 0
28-Jul-05 0 0 0 0 0 0
5-Aug-05 2 0 0 0 4 0
11-Aug-05 0 0 0 0 0 0
17-Aug-05 0 0 0 0 0 0
23-Aug-05 0 0 0 0 0 0
29-Aug-05 0 0 0 0 0 0
5-Sep-05 0 0 1 0 0 0 0 0 1
13-Sep-05 0 0 0 0 0 0 0 0 0
21-Sep-05 0 0 0 0 0 0 0 0 0
26-Sep-05 0 0 0 0 0 0 0 0 0
29-Sep-05 2 0 0 0 0 0 0 0 0
7-Oct-05 0 0 0 0 0 0 0 0 0
13-Oct-05 0 0 0 0 0 0 0 0 0
19-Oct-05 4 0 0 0 0 0 0 0 0
25-Oct-05 0 0 0 0 0 0 0 0 0
31-Oct-05 0 0 0 2 0 0 0 0 0
2-Nov-05 4 0 1 2 0 0 0 0 0
9-Nov-05 6 4 3 2 2 1 0 0 0
17-Nov-05 0 0 3 0 2 1 0 0 0
21-Nov-05 0 0 3 0 2 1 0 0 0
25-Nov-05 0 0 3 0 0 1 0 0 0
1-Dec-05 0 0 2 0 0 1 0 0 0
7-Dec-05 2 0 3 0 0 1 3 0 0
13-Dec-05 2 0 3 0 0 1 0 0 0
19-Dec-05 0 0 2 0 0 1 2 0 0
28-Dec-05 0 0 2 0 0 1 0 0 0
3-Jan-06 0 0 2 0 0 0 0 0 0
11-Jan-06 0 0 1 0 0 0 0 0 0
16-Jan-06 0 0 0 2 0 0 0 0 0
19-Jan-06 0 0 0 0 0 0 0 0 0
27-Jan-06 40 0 1 0 0 0 0 0 0
2-Feb-06 2 0 2 0 0 0 0 0 0
8-Feb-06 0 0 2 0 0 0 0 0 0
14-Feb-06 2 2 2 0 0 0 0 0 0
20-Feb-06 0 2 1 2 0 0 0 0 0
27-Feb-06 4 2 2 2 0 1 0 0 0
6-Mar-06 86 2 3 0 0 1 0 0 0
14-Mar-06 4 4 4 4 2 2 10 0 0
22-Mar-06 4 4 4 0 2 2 0 0 0
27-Mar-06 0 4 4 0 0 1 0 0 0
30-Mar-06 14 4 9 2 0 2 4 0 0
5-Apr-06 0 4 4 0 0 2 0 0 0
11-Apr-06 2 2 4 0 0 2 0 0 0
18-Apr-06 2 2 4 0 0 2 0 0 0
20-Apr-06 2 2 4 0 0 2 2 0 1
24-Apr-06 0 2 4 0 0 1 0 0 1
1-May-06 2 2 4 0 0 0 0 0 1
9-May-06 37 2 4 0 0 0 0 0 1
17-May-06 28 2 9 0 0 0 0 0 0
22-May-06 2 2 8 0 0 0 0 0 0
25-May-06 0 2 8 0 0 0 0 0 0
1-Jun-06 60 28 15 0 0 0 0 0 0
7-Jun-06 4 4 16 0 0 0 0 0 0
13-Jun-06 0 2 16 0 0 0 0 0 0
19-Jun-06 0 0 16 0 0 0 0 0 0
26-Jun-06 2 2 16 0 0 0 0 0 0

* SEPP (Waters Victoria) specifies for primary contact recreational activities Rolling 30 d Median less than 35 orgs/100 ml
** SEPP (Waters Victoria) specifies for primary contact recreational activities Rolling 60 days 75th Percentile less than 150 orgs/100 ml

Date Beach 4 Beach 5 Beach 6
Day Result 30 Day Median* 75th Perce-
ntile **		 Day Result 30 Day Median* 75th Perce-
ntile **		 Day Result 30 Day Median* 75th Perce-
ntile **
4-Jul-05 0 2 0
12-Jul-05 0 4 2
20-Jul-05 0 4 4
25-Jul-05 2 2 0
28-Jul-05 0 0 0 2 2 2
5-Aug-05 0 0 0 2 0 2
11-Aug-05 0 0 4 2 2 2
17-Aug-05 0 0 2 2 0 0
23-Aug-05 0 0 2 2 4 2
29-Aug-05 0 0 0 2 0 0
5-Sep-05 0 0 0 0 2 3 0 0 2
13-Sep-05 0 0 0 0 0 3 0 0 2
21-Sep-05 0 0 0 0 0 2 0 0 2
26-Sep-05 0 0 0 0 0 2 0 0 1
29-Sep-05 2 0 0 0 0 1 2 0 2
7-Oct-05 0 0 0 6 0 2 4 0 2
13-Oct-05 0 0 0 0 0 2 0 0 2
19-Oct-05 0 0 0 0 0 1 0 0 1
25-Oct-05 0 0 0 0 0 0 0 0 1
31-Oct-05 0 0 0 4 0 0 0 0 0
2-Nov-05 0 0 0 0 0 0 0 0 0
9-Nov-05 0 0 0 4 0 2 12 0 1
17-Nov-05 0 0 0 14 4 4 0 0 1
21-Nov-05 0 0 0 0 4 4 0 0 1
25-Nov-05 0 0 0 6 4 5 0 0 1
1-Dec-05 0 0 0 4 4 5 0 0 0
7-Dec-05 2 0 0 16 6 5 4 0 0
13-Dec-05 0 0 0 6 6 6 0 0 0
19-Dec-05 0 0 0 2 6 6 0 0 0
28-Dec-05 6 0 0 10 6 8 0 0 0
3-Jan-06 0 0 0 5 6 8 2 0 1
11-Jan-06 0 0 0 8 6 9 2 0 2
16-Jan-06 0 0 0 32 8 12 0 0 1
19-Jan-06 0 0 0 2 8 9 0 0 1
27-Jan-06 0 0 0 0 5 9 0 0 1
2-Feb-06 0 0 0 4 4 9 0 0 1
8-Feb-06 0 0 0 3 3 9 0 0 1
14-Feb-06 0 0 0 0 2 7 2 0 1
20-Feb-06 0 0 0 2 2 6.5 0 0 1
27-Feb-06 0 0 0 10 3 9 6 0 2
6-Mar-06 2 0 0 8 3 8 6 2 2
14-Mar-06 2 0 0 16 8 9 0 2 2
22-Mar-06 0 0 0 0 8 9 0 0 1
27-Mar-06 0 0 0 10 10 9 0 0 1
30-Mar-06 0 0 0 10 10 10 0 0 1
5-Apr-06 0 0 0 0 10 10 0 0 1
11-Apr-06 0 0 0 6 6 10 0 0 1
18-Apr-06 0 0 0 0 6 10 0 0 1
20-Apr-06 2 0 1 0 0 10 0 0 0
24-Apr-06 0 0 1 3 0 10 0 0 0
1-May-06 0 0 1 0 0 9 0 0 0
9-May-06 0 0 0 8 0 9 0 0 0
17-May-06 0 0 0 29 3 9 0 0 0
22-May-06 0 0 0 0 3 9 0 0 0
25-May-06 0 0 0 0 0 7 0 0 0
1-Jun-06 0 0 0 2 2 4.5 0 0 0
7-Jun-06 0 0 0 2 2 4.5 2 0 0
13-Jun-06 0 0 0 4 2 3.5 2 0 0
19-Jun-06 0 0 0 5 2 4.5 0 0 0
26-Jun-06 0 0 0 0 2 4.5 0 0 0

* SEPP (Waters Victoria) specifies for primary contact recreational activities Rolling 30 d Median less than 35 orgs/100 ml
** SEPP (Waters Victoria) specifies for primary contact recreational activities Rolling 60 days 75th Percentile less than 150 orgs/100 ml

Top of page

Discharges to air

Gas emissions from one of the engines in the outfall pumping station were sampled on 19 June 2006 for nitrogen oxides, carbon monoxide, sulphur dioxide, hydrogen sulphide and volatile organic compounds as required by the discharge licence. The following table contains a comparison between the test results and the discharge licence limits with all results demonstrating compliance.

Parameter Maximum Rate (g/min) Maximum Concentration (mg/m3)
Limit Result Limit Result
Sulphur Dioxide * 7.5 4.5 40 70
Hydrogen Sulphide 0.5 0.088 2 0.13
Nitrogen oxides 500 140 2600 2000
Carbon Monoxide 300 86 2600 1300
VOC 20 0.31 100 4.6

* Sulphur dioxide data reported here are from a second test conducted on 10 August 2006 as Sulphur dioxide results from the 19 June 2006 test were considered anomalous and the measurements repeated.

Three of the five outfall pumping engines are being replaced with electrical motors. After this change, Melbourne Water will effectively eliminate emissions from the outfall pumping station during normal operation. The remaining two engines will be used only during emergencies. At the time of publishing this report, two of the old engines had been removed and the third will be removed within six months.

Click on the following links for information on Melbourne Water’s: