Water and wastewater challenges for marae

Supply of adequate drinking water and the removal of polluted waters are two fundamental infrastructural needs of communities – so it goes without saying that the generation, collection, treatment and disposal of waste is a central and necessary component of a functioning marae.

Since 2009, Tainui Awhiro, Ngāi Tai, Te Roroa, NIWA and other marae management committees around the country have been working together to characterise water and wastewater challenges for marae, and identify treatment options that better meet the aspirations of Māori for improved water and wastewater management.

This article presents some of the findings of this initial research, particularly the work completed to better understand wastewater management challenges for marae.  

Method

A questionnaire was used to guide face-to-face interviews with marae representatives. The questionnaire aimed to obtain site-specific information regarding marae usage, facilities and water and wastewater management systems.

A total of 22 questionnaires were completed by marae situated mainly in the North Island; the majority of whom were situated in rural locations in the Tainui (45%) and Te Tai Tokerau (26%) regions.

So what’s different about marae wastewater?

The questionnaire confirmed many characteristics of marae usage, including the many types of events that marae host, and that marae usage (in terms of numbers of people) is also highly variable.

The key difference in marae wastewater production is the variability in flows and loads that can be experienced throughout the year:

  • Over a year participating marae hosted between 8 and 100 events.
  • Hosted events typically lasted between 1 and 3 days.
  • Tangihanga were associated with the highest influx of people, with estimates of between 20 and 500 people present at the marae at any one time.
  • Unveilings, birthdays, weddings and reunions occurred less often, but also involved very large numbers of people (between 30 and 400 people).

Finding out about marae wastewater systems

Key findings of the questionnaire regarding existing marae wastewater systems included:

  • Grey and black water are often managed through a combined wastewater system.
  • Marae wastewater treatment and dispersal systems typically consist of septic tanks draining to soil infiltration fields.
  • Approximately 55% of respondents reported issues with their wastewater systems (20% reported frequently having issues and 35% reported sometimes having issues).
  • There is often limited funding available for system maintenance and upgrades.

The questionnaire responses were considered alongside the results of a survey by Te Puni Kōkiri (TPK, 2012; 544 responses) to provide a fuller view of the status of marae water and wastewater systems, needs and aspirations.

The findings of the TPK study were similar to those from the NIWA questionnaire. In terms of a more nationwide picture, TPK (2012) highlighted that of the 352 respondent marae who have their own septic tank (or similar) system about 76% of these reported that their system was adequate for the needs of the marae, while 24% reported that their septic system was inadequate.

Issues and challenges for marae systems

The types of problems participating marae had with their systems included:

  • Excessive septic tank maintenance requirements (i.e., emptying more than once per year).
  • High incidences of blockages.
  • High incidences of overflows.
  • Odours from the system.

Other issues reported with marae wastewater systems included:

  • Distance/cost from service centre.
  • Land slips/movement.
  • Kinked pipes restricting water flow.
  • Heavy rains and flooding (high water table and close to surface waters).
  • Can’t put hāngi down in the ground due to contaminated ground or high water table.
  • Lack of knowledge (or plans if they exist) of where existing plumbing and land discharge systems (e.g., from the septic tank) goes and lack of information being passed onto the current marae management committee.
  • Existing system does not meet current codes/standards (e.g., undersized septic tanks).
  • No grease trap for kitchen wastewaters.

Almost all participating marae reported multiple types of water bodies in close proximity. Sixty eight per cent of marae participating in the NIWA survey perceived that there were potential issues with the way their wastewater was dispersed locally.

About half the marae who responded to the survey plan to upgrade their wastewater systems, including shower and toilet facilities over the next 1–3 years. This compares with 40% of marae in the TPK survey that noted their shower/toilet facilities or wharekai required attention.

While many marae communities are aware of local wastewater issues, addressing the issues is often thwarted by a lack of tenable and affordable solutions. This is particularly the case in rural/isolated communities with constraints on land availability, sensitive receiving environments, and high marae usage.

In addition, ageing infrastructure (and need for replacement and/or upgrade), increased pressure on land and the receiving environment along with development aspirations further highlight the need for innovative and robust wastewater management solutions.

While there are many interrelated issues that need to be addressed to improve this situation, this project has highlighted an appetite and need for practical demonstrations of improved water management approaches in different communities and situations.

Where to from here?

Unsurprisingly, marae generally have limited wastewater treatment and disposal alternatives available to help them cope with large events and effectively manage the resulting variation in wastewater flows and loads.

The questionnaire results confirmed the need for further consideration and development of robust engineering design parameters (including appropriate design flow and load assumptions) that reflect the unique challenges and characteristics of wastewater from marae and similar communities.

The research being conducted (as part of the “Strengthening the Resilience of Marae and Community Water and Wastewater Infrastructure Project”) aims to assist in developing robust design parameters for marae on-site wastewater systems and provide real world examples of robust wastewater management systems that address the unique challenges of marae and similar communities.

The specific work underway to address these needs include:

  • Further monitoring and assessment of typical marae water usage and occupancy.
  • Wastewater monitoring, installation of trial greywater treatment wetland, and continued performance monitoring at the Kōkiri Centre, Whāingaroa.
  • Developing auditing and decision support tools that will better assist Māori to identify and implement wastewater management options that are effective and consistent with tikanga Māori.

References

Te Puni Kōkiri  (2012). Te Ora O Te Marae I 2009 – The Status of Marae in 2009. Te Puni Kōkiri Report.

Williams, E.K., Rickard, D., Maxwell, K.H., Patuawa, T., Iti, W., Tanner, C., Stott, R. (2014)  Water and Wastewater Challenges for Marae. Proceedings of 2014 NZ Land Treatment Collective Conference. Hamilton.

Williams, E.K., Rickard, D., Maxwell, K.H., Patuawa, T., Iti, W., Tanner, C., Stott, R. (2012)  Status of marae water and wastewater infrastructure: Results of a questionnaire survey.  August 2012. NIWA Report.

Contact

Erica Williams
Erica.Williams@niwa.co.nz

Tel: 04 386 0366

*These photographs and images have been taken and collated in partnership between NIWA and participating marae for the purpose of the project. Permission to re-use these photographs and images for any purpose must be sought and obtained from NIWA and the partnering marae.
Marae road signage, NZ. [NIWA]*
Torere Marae ablution block, Torere Marae, Torere, East Coast, NZ. [Torere Marae/NIWA]*
Older style kitchen grease trap/sump. [NIWA]*
Inlet to Conventional Septic Tank Chamber. [NIWA]*
Types of problems participating marae have with their wastewater treatment systems.
Onsite wastewater system vents and infiltration area. [NIWA]*
Experimental wastewater treatment reed beds installed at Pukete Wastewater Treatment Plant. The performance of this installation is currently being monitored. [NIWA]*