Hahei Wastewater

Wastewater in Hahei is made up of two sources – Storm water/General run off and Sewage. On this page, we present background information on both.

Storm Water

Storm Water in Hahei is collected in the following catchments

Wigmore – The Wigmore Stream and its tributaries originate towards Link Road, and flows down past the sewage treatment plant before discharging into the ocean at the southern end of Hahei Beach. The Wigmore receives run from farms. treated sewage, and storm water in Hahei Village.
Tutaritari – The Tutaritari Stream originates in the valley behind Grange Road, then flows over farm land, through Hahei Village, and discharges on to the middle Hahei Beach near the Beach Car Park.

TCDC is responsible for managing storm water in Hahei Village in the area within the green dotted line shown on this map. For more details go to click here.

Sewage

Hahei has a TCDC operated municipal sewage system that provides sewage treatment to 140 properties in Hahei. The area covered shown in the map. Click here for more details.

For details of the treatment plant and its operation, you can download the RMA application prepared by Harrison Grierson, TCDC’s consultants by clicking here. Hahei Sewage System RMA Application. The application was approved and a new Consent was issued that is effective up 2030. You can download the consent here. Hahei WWTP Consent renew2030

The area of Hahei not covered by the TCDC sewage treatment plant has a variety of treatment plants, depending on when the property was developed. Older properties have septic tanks, while more recent builds have modern onsite sewage treatment plants.

Waikato Regional Council Role

In accordance with the Resource Management Act (RMA) the Waikato Regional Council (WRC) has responsibility for monitoring our coastal environment, including stream run off into the ocean.

When discharge consents are issued to organisations such as Thames Coromandel District Council, monitors discharge quality and produces reports annually on specific plans.

WRC has undertakes research in coastal water quality. You can read their most recent report here. TR 20162f07 Snapshot Of Coastal Stream Mouth Water Quality In The Coromandel Area January2fFebruary 2015 3435990

Sewage Treatment Plant Performance.

Each year, Veolia, TCDC’s plant operator, provides a detailed report of the plants performance. You can download the reports here

2017 Report Veolia 2017 Hahei Wastewater Treatment Plant Report,
2017 Detailed Data Spreadsheet, 0416 0317 Hahei WWTP Annual Report 117888
2018 Report Veolia 2018 Hahei Wastewater Treatment Plant Report.
2018 Detailed Data Spreadsheet 0417 0318 Hahei WWTP Annual Report 135636.

These reports show that the plant was compliant in 2017, but failed to meet required performance standards, as set out in the Discharge Consent, in 2018. Here is a summary


	2018 Actual Performance		Consent Max
	90th Percentile	Average	90th Percentile	Average
Suspended solids (g/m3)	8.6	3.5	20	10
cBOD5 (g/m3)	10.8	3.8	20	10
Escherichia coli (cfu/100 mL)	953.0	370.5	20	10
Total Ammoniacal nitrogen (g/m3)	51.0	22.4	15	10
Total Kjeldahl Nitrogen (g/m3)	33.6	13.9	20	15
Total Phosphorus (g/m3)	13.2	7.9	20	14

Sewage Treatment Plant Performance WRC Report 2020

Each year, Waikato Regional Council prepares a Compliance Report. You can read the latest report here. WRC Site Compliance Report 60462 Hahei WWTP

A summary of WRC’s recommendations are;

Improvements have occurred for site compliance in this audited period; however, some outstanding matters require action as detailed above
The plant discharge quality is improving; however, the discharge parameters are not yet in full compliance. It is recommended the abatement notice remain in place until such time that TCDC provides updated data showing compliance with all average and 90th percentile limits. This may be achievable in the near future
A letter of direction is issued regarding the outstanding matters detailed above
Do not consider escalation is required for this site based on improved compliance state.

Sewage Treatment Plant Performance Reviews for 2020/21 by Tonkin & Taylor and Veolia

Each year, in accordance with the RMA Consent, TCDC must arrange for Veolia and an independent adviser to report on the sewage treatment plant’s performance. Here are the reports

Tonkin &Taylor Report. You can download their report here.

210617. Hahei WWTP 2021 Ecological Monitoring Report Final1.

It shows that the plant is operating in accordance with its resource consent. Their only recommendation to TCDC is

“…Veolia notify TCDC of the high coliform bacteria concentrations results so that signage can be checked and reviewed for warnings of swimming and shellfish collection in the estuary mouth.”