A plan to connect all city marae to the reticulated sewers is recommended for approval by the council Environment Committee for addition into the Long Term Plan.

Four marae; Hangarau, Waimapu, Wairoa and Tamapahore are to be recommended for connection as part of the 2018/28 LTP.

Connecting the four marae to the sewers is estimated to cost about $1.175m, with estimates varying among the marae depending on their distance from the existing network.

Four of the 11 marae in Tauranga are already connected to the waste water system; Huria, Hairini, Maungatapu and Whareroa.

'They were serviced at the time Tauranga reticulated in the 1980s, on the same basis that everyone else was,” says council asset planning and information manager Graeme Jelley.

'The capital cost was picked up by the city and then you go onto the rates basis the uniform annual charge the same as everyone else.”

Two Matapihi marae, Waikari and Hungahungatoroa, are in the process of being connected, as a result of the southern pipeline project crossing the peninsula.

'That contract is going to tender very soon, it's anticipated they should be connected up by the end of the financial year.”

The unconnected marae rely on septic tanks of unknown condition, and drainage fields for treatment of wastewater, states the Septic tanks are considered appropriate for treating and disposing of sewage in low-density development where ground conditions are suitable. They are generally not suitable for high-density development/high demand where large numbers of people gather or for low-lying land with a high water table.

Development has encroached to the point where marae formerly on the city fringes are now surrounded by urban areas, and the variety of cost estimates reflects how close development has gotten to them, says Graeme.

'Hangarau at Bethlehem ($65,000) and Tamapahore at Maungatawa ($110,000) are both very close, just a few meters away,” says Graeme.

Wairoa at Bethlehem has a cost estimate of $300-550,000. Waimapu Marae has a capital budget of $450,000.

Two welcome Bay marae, Te Whetu-O-Te Rangi and Tahuwhakatiki Marae will take longer to sort out. Tahuwhakatiki Marae is situated within Tauranga City while Te Whetu O Te Rangi Marae is in the Western Bay of Plenty District, just 100m outside the city boundary.

Connecting them to the city sewers will involve about 4km of pipe, individual pump stations at each marae and a large pump station on marae or other land. The estimated connection cost is between $1.5-2m for both marae.

They'll be considered after the completion of the Welcome Bay/Ohauiti urban growth study and subsequent land use decisions.

The use of marae as emergency shelter during civil defence emergencies is a factor weighing the staff recommendation says Graeme.

It's based on the service that marae have provided in times of disaster and civil defence emergencies, and we've seen that recently in two disasters, the Kaikoura earthquake and the Edgecumbe flood where the marae was where most of the people who were displaced were housed for the first day or two after the event.

'Civil Defence are very aware of that, and are starting to work with marae to have them on standby in the case of CD emergency. They are ideally set up for that, and it's with that background in mind we are recommending the inclusion of those marae in the waste water system.