Seaview Odour Neutraliser Trial Shutdown
Following feedback from the community regarding the odour neutralisers at the Seaview Wastewater Treatment Plant, a trial shutdown was completed from Wednesday 4th December, to Wednesday 18th December. Community feedback was collected throughout this period, and continued to be collected for two weeks once the odour neutralisers were turned back on to set a 'baseline' of responses.
This was to help understand whether the smell is better, worse, or the same when the odour neutralisers are on, or off.
Following the conclusion of the Odour Neutraliser Trial Shutdown and Survey on January 2nd, Wellington Water have made a recommendation to Hutt City Council that the odour neutralisers only be used at times when there is a significant risk of increased odour levels, i.e. when plant maintenance is being completed. Hutt City Council have agreed with this recommendation, effective immediately.
Following a thorough review of all 258 survey responses, it became clear that survey results were inconclusive. 241 were received in the two weeks that the odour neutralisers were turned off, and 17 in the two weeks after the odour neutralisers were turned back on. There were many variables which influenced responses, like weather and plant operations/maintenance. Both have a significant impact on odour levels, and plant operations in particular improved significantly in the second half of the survey period.
Trial Shutdown Results
Rate the smell between 1 to 5 (5 being worst)
Trial Part 1 - 4 to 18th December 2024
DATE |
TOTAL |
RATED 1 or 2 |
RATED 3 |
RATED 4 or 5 |
4 December 2024 |
14 |
6 |
1 |
7 |
5 December 2024 |
18 |
6 |
3 |
9 |
6 December 2024 |
119 |
4 |
23 |
92 |
7 December 2024 |
17 |
3 |
7 |
7 |
8 December 2024 |
3 |
2 |
0 |
1 |
9 December 2024 |
12 |
5 |
1 |
6 |
10 December 2024 |
6 |
4 |
0 |
2 |
11 December 2024 |
7 |
3 |
1 |
3 |
12 December 2024 |
9 |
1 |
2 |
6 |
13 December 2024 |
4 |
1 |
0 |
3 |
14 December 2024 |
2 |
1 |
1 |
0 |
15 December 2024 |
2 |
1 |
0 |
1 |
16 December 2024 |
7 |
3 |
2 |
2 |
17 December 2024 |
6 |
1 |
2 |
3 |
18 December 2024 |
15 |
2 |
4 |
7 |
|
241 |
43 |
47 |
149 |
Note: Two people on 18 December did not leave a rating |
|
Trial Part 2 - 19 December 2024 - 2 January 2025
DATE |
TOTAL |
RATED 1 OR 2 |
RATED 3 |
RATED 4 OR 5 |
19 December 2024 |
1 |
0 |
0 |
1 |
20 December 2024 |
4 |
0 |
0 |
4 |
26 December 2024 |
1 |
0 |
1 |
0 |
No date provided |
11 |
4 |
2 |
5 |
|
17 |
4 |
3 |
10 |
How does the smell compare to previous months?
Trial Part 1 - 4 to 18th December 2024
DATE |
TOTAL |
ABOUT THE SAME |
NOT AS BAD |
WORSE |
|
4 December 2024 |
13 |
2 |
5 |
6 |
|
5 December 2024 |
18 |
4 |
7 |
7 |
|
6 December 2024 |
119 |
53 |
18 |
47 |
|
7 December 2024 |
17 |
9 |
5 |
3 |
|
8 December 2024 |
2 |
0 |
1 |
1 |
|
9 December 2024 |
10 |
4 |
5 |
1 |
|
10 December 2024 |
5 |
0 |
3 |
2 |
|
11 December 2024 |
6 |
0 |
4 |
2 |
|
12 December 2024 |
9 |
4 |
2 |
3 |
|
13 December 2024 |
3 |
2 |
0 |
1 |
|
14 December 2024 |
2 |
0 |
1 |
1 |
|
15 December 2024 |
2 |
0 |
1 |
1 |
|
16 December 2024 |
7 |
2 |
4 |
1 |
|
17 December 2024 |
6 |
4 |
1 |
1 |
|
18 December 2024 |
15 |
4 |
8 |
3 |
|
|
234 |
88 |
65 |
80 |
Trial Part 2 - 19 December 2024 - 2 January 2025
DATE |
TOTAL |
ABOUT THE SAME |
NOT AS BAD |
WORSE |
|||
19 December 2024 |
1 |
1 |
0 |
0 |
|||
20 December 2024 |
4 |
0 |
0 |
4 |
|||
26 December 2024 |
1 |
1 |
0 |
0 |
|||
No date provided |
11 |
0 |
5 |
6 |
|||
|
17 |
2 |
5 |
10 |
Of responses rating the odour at 4 or 5, how did the odour compare to previous months?
Trial Part 1 - 4 to 18th December 2024
DATE |
RATED 4 OR 5 |
ABOUT THE SAME |
NOT AS BAD |
WORSE |
4 December 2024 |
7 |
1 |
0 |
6 |
5 December 2024 |
9 |
3 |
1 |
5 |
6 December 2024 |
92 |
44 |
4 |
45 |
7 December 2024 |
7 |
2 |
3 |
2 |
8 December 2024 |
1 |
0 |
0 |
1 |
9 December 2024 |
6 |
2 |
3 |
1 |
10 December 2024 |
2 |
0 |
0 |
2 |
11 December 2024 |
3 |
0 |
1 |
2 |
12 December 2024 |
6 |
3 |
0 |
3 |
13 December 2024 |
3 |
2 |
0 |
1 |
14 December 2024 |
0 |
0 |
0 |
0 |
15 December 2024 |
1 |
0 |
0 |
1 |
16 December 2024 |
2 |
1 |
0 |
1 |
17 December 2024 |
3 |
2 |
0 |
1 |
18 December 2024 |
7 |
3 |
1 |
3 |
|
|
63 |
13 |
74 |
Trial Part 2 - 19 December 2024 - 2 January 2025
19 December 2024 |
1 |
1 |
0 |
0 |
20 December 2024 |
4 |
0 |
0 |
4 |
26 December 2024 |
0 |
1 |
0 |
0 |
No date provided |
5 |
0 |
0 |
5 |
|
|
2 |
0 |
9 |
|
|
|
|
|
Location where odour was smelt (4 December 2024 - 2 January 2025)
SUBURB |
TOTAL |
1 OR 2 |
3 |
4 OR 5 |
Alicetown |
2 |
0 |
2 |
0 |
Boulcott |
2 |
0 |
0 |
2 |
Eastbourne |
4 |
0 |
0 |
4 |
Epuni |
1 |
0 |
0 |
1 |
Gracefield |
15 |
3 |
0 |
12 |
Lower Hutt |
22 |
1 |
6 |
15 |
Moera/Hutt Park |
25 |
2 |
4 |
18 |
Naenae |
2 |
0 |
2 |
0 |
Petone |
5 |
0 |
0 |
5 |
Point Howard |
5 |
1 |
2 |
2 |
Seaview |
86 |
21 |
7 |
59 |
Sorrento Bay |
5 |
4 |
0 |
1 |
Wainuiomata |
6 |
0 |
3 |
3 |
Waiwhetū |
63 |
16 |
17 |
29 |
Waterloo |
16 |
1 |
3 |
12 |
Woburn |
7 |
0 |
1 |
6 |
|
266 |
49 |
47 |
169 |