Unless there is a council sewerage scheme planned for your area, any new septic systems installed must be of an approved model.  The table below highlights the systems approved for installation in the Rotorua lakes’ catchments.  All systems shown may be installed elsewhere in the Bay of Plenty.

The wastewater models names in the table are ‘clickable’ links, which will take you to the report describing the trial results in more detail.

	Approved for installation  in Rotorua Catchments?	Irrigation Pump Included in Test?	Measured Power Use (kWh) per day	Equivalent Annual Power Cost
Trial 1 (2005 – 2006)
Devan Blue DB9000 NRS	-	Yes	6.3	$517
Hynds Lifestyle	-	Yes	1.7	$140
Innoflow AdvanTex AX20	Yes	No	0.6	$49
Oasis Membrane MBR	-	Yes	7.3	$600
Smith and Loveless (MicroFAST 0.5)	-	No	7.2	$591
Biolytix BF6 2500 PAT	-	Yes?1	0.2	$16
Supertreat SB440 (N12)	Yes	Yes	10.8	$887
Trial 2 (2006 – 2007)
Bio-Microbics Micro FAST ® 0.9	-	Yes	8.9	$731
Devan Blue 9000 NRS	-	Yes	2.7	$222
Hynds Lifestyle “Ultimate”	Yes	Yes1	2.2	$181
Reflection Textile ‘EW’	-	Yes1	2.5	$205
RX Plastics Airtech 9000 NR	Yes	Yes	5.3	$435
RX Plastics Airtech 9000		Yes	4.9	$402
Waipapa Tanks Econo Treat P-10-2		Yes	1.3	$107

Notes on Power Usage

1 The irrigation pump trialled in the Biolytix and Reflection treatment system is too small for almost all irrigation applications.  Typically electricity use for irrigation pumps in ‘real life’ situations is around 0.5 to 1.0 kWh per 1000 litres (ie. approximate average household daily flow).  This will vary depending on pump efficiency, difference in elevation, distance to irrigation, pipe size etc.

2 The electricity usage figures presented need to be treated with caution.  Various factors could influence them including blockages and pump efficiency.  Note that only some systems included irrigation pumps in the trial. 

3 The trial’s primary purpose was to demonstrate the ability of advanced wastewater systems to reduce nutrients.  To achieve this requires a greater degree of recirculation and/or aeration (and therefore electricity) than would typically be required.  It is therefore likely that the ‘standard’ model of the above systems (where available) will use considerably less electricity than what was measured. 

4.  The annual power cost was calculated using a nominal cost per kWh of 20 cents plus GST.  The exact cost will vary depending on the region, pricing plan and discounts available.

Other factors to consider when choosing an advanced wastewater system

Choosing a system

OSET: Rotorua Lakes Catchments - Fact Sheet

If you want to install an advanced system, rule 13 of the On-site Effluent Treatment Regional Plan applies. 

Existing conventional septic tank systems in Rotorua Lakes' Catchments

Unless connected to a sewer by December 2010 most conventional septic tanks systems in the  catchments of Rotorua, Rotoiti, Rotoehu, Okaro and Okareka, will be required to upgrade to an approved advanced waste water treatment system.  Those in Tarawera, Rotoma, and Hamurana have until December 2014. 

Rotorua District Council has plans to construct a sewerage system for the communities of Gisborne Point, Hamurana, Hinehopu, Rotoma, Okareka, and Tarawera.

Refer to rule 2 of the On-Site Effluent Treatment Regional Plan for more information.