Recent and historic wastewater overflows

Lists of recent and historic wastewater overflows.

2026 overflows

This page is updated as soon as possible; however, it is a manual process, so there may be delays during busy periods.

If you see signs about polluted water around the city and have further questions, please contact us. Pollution may take up to two days to completely clear after the discharge has ceased.

Event identification (ID) numbers are not consecutive, due to false alarms, etc. 

Overflow reported	Overflow ceased	ID	Overflow location	Receiving waterway	Cause
10/01/2026 3pm	10/01/2026 5pm	597	Corsair Bay Beach, Lyttelton	Lyttelton Harbour	Blockage (rubbish)
15/01/2026 6.40pm	15/01/2026 9pm	598	Corner of Ferry Road and Richardson Terrace, Woolston	Heathcote River	Wet weather
17/01/2026 10.40am	17/01/2026 12:20pm	599	Te Ara Crescent, Diamond Harbour	Lyttelton Harbour	Blockage (roots)
7/02/2026 10.30am	7/02/2026 2.30pm	601	Te Ara Crescent, Diamond Harbour	Lyttelton Harbour	Burst drinking water main
16/02/2026 1.00pm	18/02/2026 1.15am	603	Akaroa Fire Station, Akaroa	Akaroa Harbour	Wet weather
16/02/2026 8.00pm	19/02/2026 1.00pm	605 606 609 611 613 618 619	Heathcote River, Cashmere to Woolston	Heathcote River	Wet weather
17/02/2026 1.30am	19/02/2026 1.00pm	607	Diamond Harbour Bowling Green, Diamond Harbour	Lyttelton Harbour	Wet weather
17/02/2026 3.30am	18/02/2026 11.00am	608	Marine Drive, Charteris Bay	Lyttelton Harbour	Wet weather
16/02/2026 10.40pm	17/02/2026 4.00pm	610	Corner of Kilmore Street and Fitzgerald Ave, Central City	Avon River	Wet weather
17/02/2026 12.50am	17/02/2026 2.00pm	612	Corner of Avonside Drive and Retreat Road, Avonside	Avon River	Wet weather
17/02/2026 6.40am	17/02/2026 11.20am	614	Jetty Road, Governors Bay	Lyttelton Harbour	Wet weather
17/02/2026 7.00am	17/02/2026 11.30am	615	Erskine Point, Lyttelton	Lyttelton Harbour	Wet weather
17/02/2026 7.40am	18/02/2026 11.00am	616	Sandy Beach, Governors Bay	Lyttelton Harbour	Wet weather
17/02/2026 4.00pm	18/02/2026 4.50pm	617	Tikao Bay Beach, Tikao Bay	Akaroa Harbour	Wet weather
20/02/2026 4.30pm	22/02/2026 11.00pm	620	Main Road, Governors Bay	Lyttelton Harbour	Blockage in the pumping main
1/03/2026 11.30pm	2/03/2026 1.15pm	621	Corner of Eastern Terrace and Sandwich Road, Beckenham	Heathcote River	Wet weather
1/03/2026 9.30pm	2/03/2026 5.10pm	622	Corner of Linwood Avenue and Hargood Street, Bromley	Estuary	Wet weather
1/03/2026 9.20pm	2/03/2026 1.40pm	623	Corner of Cashmere Road and Shalamar Drive, Cashmere	Heathcote	Wet weather
9/05/2026 8.10am	9/05/2026 11.25am	626	Waipapa Avenue, Diamond Harbour	Lyttelton	Blockage (roots)
29/05/2026 10.30am	29/05/2029 12.20pm	627	Medbury Terrace, Fendalton	Waimairi Stream	Blockage (debris)
8/06/2026 9.30pm	8/06/2026 10.30pm	628	Hollis Avenue, Cashmere	Heathcote River	Blockage (roots)
26/06/2026 1.35pm	26/06/2026 2.55pm	631	Regents Park Drive, Casebrook	Styx River	Blockage (fat)