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eatmenQuality

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nt Quan

m3 per day (

effluent flow

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ave resulted

curred for:

rch 2011. D

sue was not

.

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eplaced by outflooses. The result w

M_GWWTP Effluent Q

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Table 1 –

2009‐2

2010‐2

2011‐2

2012‐2

2013‐2Notes: *replacemfaulty pe

Across t

Table 2 –

Average

Median

Max dai

Summer

Winter d

Notes: co

It has b

contribu

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flows m

average

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WastewConditioStream. based othe com

Table 2 ‐

Yea

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2009‐2

2010‐2

2011‐2

2012‐2

2013‐2Notes: *

table pre

3 R. P. a. B.Treatment



– GWWTP Ann

2010

2011*

2012

2013

2014 * As noted ament of the mriod may have

he period pr

– GWWTP Flo

e daily discha

Daily Discha

ly discharge

r daily averag

daily average

ount = 1914, *

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uted to by in

ood that up

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per capita

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Flow monito

ar

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rd

2010

2011

2012

2013

2014 Running Geo

esents the ave

. Ellwood, “Chapt

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istics for year

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Compliance

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s indicate th

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2014

FC

ean 90

0 25

13

13

30

32

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Sewage Effluent,

M_GWWTP Effluent Q

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resulted in the note that th10.

ved?

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he GWWTP

lculations it

f wet weathe

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Zealand

10 Reports\Greytown

s occurred du

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Figure 4



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10 Reports\Greytown

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CA (1998) asentration froreduced hydiability in BOter as a resu

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plication\GWWTP AEE

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Figure 10



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nths, likely d

has also bee

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10 Reports\Greytown

s (mg/L) from

9 for effluen

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WWTP; Januar

plication\GWWTP AEE

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M_GWWTP Effluent Q

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Figure 11

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WTP; January

Zealand

10 Reports\Greytown

TP concentr

be expected

ons indicate

Pond effluent

age of 4.9 mg

WWTP; Januar

y 2009 to June


rations with

in pond sys

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plication\GWWTP AEE

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ity from GWW

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and 1010, New Z


WTP; January

GWWTP; Jan

Zealand

10 Reports\Greytown

y 2009 to June

nuary 2009 to


e 2014(total d

o June 2014(to

plication\GWWTP AEE

ataset)

otal dataset)

Final\Appendix 6 – MMM_GWWTP Effluent Q

Page

uality

e | 10



pH (labo

Figure 15

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Figure 16

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10 Reports\Greytown

une 2014(tota

July 2009 – N

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M_GWWTP Effluent Q

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10 Reports\Greytown

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GREYTOWN WWTP EFFLUENT DATA SUMMARY

S.S. Total Solids BOD5 Total BOD Soluble NH3-N TP DRP TN F.C. E.Coli pH Temp Conductivity DO TOG Outflow

mg/L mg/L mg/L m3/d

Minimum 8.0 13.0 11.0 1.5 0.01 2.57 1.34 8.37 8 8 6.4 6.9 231.0 0.1 2.5 0

Average 63.1 312.0 42.3 7.2 11.53 5.16 4.32 20.08 2317 1568 7.9 15.1 365.1 5.2 6.5 728

25%ile 36.3 259.0 24.0 3.0 5.00 4.27 3.17 14.60 260 138 7.5 10.5 308.1 1.8 2.5 508

Median 56.5 315.0 38.0 5.0 12.50 5.23 4.30 18.90 570 400 7.7 15.5 349.6 4.3 2.8 648

75%ile 77.5 367.0 56.1 8.0 17.40 5.89 5.50 26.30 2027 1253 8.1 19.1 418.4 7.7 7.8 867

90%ile 109.0 409.8 75.4 12.0 22.84 6.68 6.07 29.04 4240 3110 8.8 21.9 471.8 11.3 12.7 1144

Maximum 292.0 720.0 118.0 59.0 28.40 11.90 6.60 39.40 33000 22000 9.8 26.2 536.0 18.8 32.7 6670

Count 170 87 167 87 133 133 170 133 167 130 107 102 102 106 20 1824

Summer (Nov - Apr) S.S. Total Solids BOD5 Total BOD Soluble NH3-N TP DRP TN F.C. E.Coli pH Temp Conductivity DO TOG Outflow

TRUE m3/d

Average 73.0 350.8 48.5 8.6 6.5 5.6 4.9 16.5 1860 827 8.1 19.5 407.9 5.9 3.9 605

25%ile 49.8 310.0 29.0 3.0 1.3 4.8 4.1 11.4 215 110 7.6 17.9 349.3 1.8 2.5 432

Median 65.0 360.5 46.0 5.0 6.2 5.5 5.0 15.7 500 300 7.8 19.2 412.1 4.8 2.5 574

75%ile 80.5 384.5 62.2 8.3 10.7 6.2 6.0 19.9 1844 900 8.5 21.6 455.7 8.3 6.0 731

90%ile 128.5 417.3 82.4 15.2 13.2 7.1 6.2 24.1 3920 1400 9.1 22.9 484.9 13.9 6.2 905

Count 100 40 97 40 63 63 100 63 99 62 48 47 47 48 9 890

Winter(May - Oct) S.S. Total Solids BOD5 Total BOD Soluble NH3-N TP DRP TN F.C. E.Coli pH Temp Conductivity DO TOG Outflow

FALSE m3/d

Average 49.1 278.9 33.5 6.0 16.1 4.8 3.5 23.3 2982 2244 7.7 11.4 328.5 4.6 8.6 847

25%ile 26.5 226.0 21.3 3.0 13.2 3.8 2.6 18.7 340 200 7.5 8.8 293.4 1.5 2.5 585

Median 43.5 273.0 29.0 4.0 16.9 4.6 3.4 24.4 710 565 7.7 10.6 317.0 4.1 3.0 752

75%ile 69.5 331.0 41.8 6.5 21.4 5.6 4.3 27.5 2600 2000 7.9 13.7 358.6 6.8 11.3 998

90%ile 87.2 377.4 58.0 9.4 23.7 6.1 5.2 29.8 7354 4090 8.3 15.9 398.5 9.6 14.0 1303

Count 70 47 70 47 70 70 70 70 68 68 59 55 55 58 11 934

Notes:

‐ Only data from 2009 onwards has been used

‐ We have deleted all F.C. and E.Coli values <=10 because these results seemed unrealistic.

‐ Approximately 6.5 years of overlapping quality and flow data from March 2005 ‐ June 2013

‐ TP effluent quality data prior to May 2009 has been excluded as looks eroneous

GREYTOWN MASS LOADS

SS BOD TN NH4‐N TP DRP

Annual Mass Load kg/yr 16777 11228 5334 3064 1370 1148

Daily Mass Load kg/d 46.0 30.8 14.6 8.4 3.8 3.1

Summer Mass Load kg/summer 8056 5358 1818 715 617 537

Summer Daily Load kg/d 44.1 29.4 10.0 3.9 3.4 2.9

Winter Mass Load kg/winter 7585 5184 3604 2486 736 549

Winter Daily Load kg/d 41.6 28.4 19.7 13.6 4.0 3.0

The above mass load information has been based on average effluent concentrations and average flow rather than a detailed analysis of daily loads.

All Year

mg/L No./100mL

mg/L No./100mL

mg/L No./100mL

town wastewater tre atment plant effluent quantity and ... · l1, 23 unio po box 375 t +64 (0)9 3...

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