The Mangawhai Community Wastewater Scheme (MCWWS) Extension Project
The MCWWS services part of the Mangawhai Drainage District through a reticulated network of pipes connecting properties to the treatment plant. A further network of pipes connects the plant to a holding dam on Browns Road Farm.
Disposal occurs through a further network of pipes on the Farm that distributes treated water on fields covering part of available farmland. The capacity of the plant can cater for about twice the number of current connections. Disposal capacity through the current irrigation reticulation is at its limit. In order to increase connections to the plant, the reticulation needs to be extended to other parts of the drainage area and the disposal capacity needs to also increase.
There are a number of options for how the reticulation network is extended, how the capacity for disposal is increased and how the extension is funded.
There is a significant amount of information regarding the system, to the left you can see historical information about the EcoCare system, below are a selection of reports.
- WSP Opus - Summary report (Stage 1) (pub. 10/09/2018)
- WSP Opus – Development of solutions (Stage 2) (pub. 18/12/2018)
- WSP Opus – Mangawhai Wastewater treatment – Disposal Field Irrigation Assessment (pub. 11/02/2019)
- WSP Opus – Mangawhai Community Wastewater treatment Plant: Future Options Development (pub. 28/11/2019)
- WSP – Mangawhai Wastewater Strategy Workshop presentation (pub. 22/05/20)
- WSP - Mangawhai Community Wastewater Scheme - Workshop Presentation and Timeline (pub. 01/06/20)
- WSP - Mangawhai WWTP Balance Tank - Concept Design (pub. 17/09/20)
- WSP - Mangawhai Wastewater Collection System recommended flow monitoring locations - Memo (pub. 15/10/20)
- WSP - Summary Letter (pub. 7/12/20)
- WSP - Mangawhai Wastewater Renewals Options Assessment - Memo (pub. 23/12/20)
- WSP - Mangawhai Wastewater Modelling - Model Build Report (pub. 23/12/20)
- WSP - Detailed Site Investigation Wastewater Treatment Plan (Thelma Road South) (pub. 22/02/21)
- Deloitte - Letter to WSP (from Deloitte) (pub. 02/06/21)
- WSP - Letter to Auditor (from Andrew Springer) (pub. 11/06/21)
- WSP - Mangawhai Balance Tank Risk of increasing flows at Thelma Road (outfall) Pump Station (pub. 14/09/21)
- WSP - Model Calibration and System Performance Planning (pub. 30/09/21)
- WSP - Thelma Road Wet well levels assessment (pub. 15/10/21)
Harrison Grierson Effluent Disposal
- Addendum 1 – Disposal Options Study (pub. 4/6/15)
- Addendum 2 – WWTP Capacity assessment and upgrade costs (pub. 4/5/2015)
- Addendum 3 - Golf Course MEDLI Modelling and Wetland Disposal (BMT WBM Pty Ltd) (pub. 3/6/2015)
Kaipara District Council
- MCWWS Wastewater Network Extension Report (pub. 11/12/2014)
- Mangawhai Wastewater Scheme Strategy and Options Report (pub. 11/08/2017)
- Reclaimed water study
Mangawhai Community Wastewater Treatment Plant (CWWTP)currently produces a treated effluent that meets international standards for beneficial reuse. The criteria given in the Environment Protection Authority Victoria Australia effluent standards for reuse show that the effluent is suitable for use as irrigation on recreational areas, provided that public access is restricted during and immediately following application. This is Class C, which makes it ideal for Golf Course irrigation, where irrigation can be overnight, with several hours before the course is used.
Kaipara District Council (KDC), local iwi and Mangawhai Golf Course (GC) have been in discussion and agree in principle that the community and KDC will mutually benefit by reusing effluent for irrigation.
The main benefits to KDC are;
- Benefits to community facility
- 15 ha of land not required for irrigation and associated infrastructure
- long term potential for greater volumes
The reports below presents the concept of an effluent reuse system for the WWTP.
- WSP - Mangawhai Community Wastewater Treatment Plan Effluent Reuse - Discussion Document Golf Course Irrigation (pub. 16/12/20)
- WSP - Mangawhai Water Reuse - Hydrogeological study - Soils (pub. 19/05/21)
- WSP - Mangawhai Water Reuse - Mangawhai Hydrology & Soil summary memo (pub. 19/05/21)
- WSP - Mangawhai Water Reuse - Hydrogeological study - Hydrology (pub. 20/05/21)
- Mangawhai Golf Course Wetland - Ecological Impact Assessment (pub. 02/06/21)
- Mangawhai effluent Reuse Golf Course Concept Solution Report (pub. 14/09/21)