Innovative thinking brings bright ideas to life
For immediate release: 20 September 2012
New uses for sea lettuce, using dairy effluent to fatten fish and a new clean-up method for Rotorua’s septic tanks –
just some of the bright ideas Bay of Plenty Regional Council staff have come up with as they go about their day-to-day
work.
The projects are being helped along under the Regional Council’s Bright Ideas Innovation Fund established in 2010 to
help fund innovative staff projects and ideas. The $30,000 fund is available for staff ideas that are likely to improve
the value of the Regional Council’s work in the community, but which fall outside standard work programmes.
Staff can apply for funding for their innovative ideas, presenting a business case to a selection panel. This year’s
winning project is an investigation into sustainable ways of disposing of sea lettuce – a continuing summer problem on
Bay of Plenty beaches.
Regional Council Tauranga Harbour programme co-ordinator Bruce Gardner is looking into the viability of using sea
lettuce for stock food, dewatering and turning it into pellets for fertiliser or using it for useful products such as
bio-gas, bio-diesel or ethanol.
Most sea lettuce collected in the last two years has gone to Tauranga’s Te Maunga compost facility, but now that Psa
disease has resulted in a significant drop-off in demand from kiwifruit orchards the facility is unable to take the
lettuce any more. Unless new uses are found, unsustainable disposal to landfill would cost the Regional Council and
Tauranga City Council up to $67,000 in a bad sea lettuce year.
Mr Gardner’s project includes trialling and monitoring using sea lettuce as fertiliser and promoting it to farmers,
orchardists and gardeners, as well as investigating other options such as turning it into pellets for stock feed,
biodigesting and fertiliser.
Earlier Bright Ideas projects are also starting to have success. Regional Council Environmental Scientist Shane
Iremonger’s project to establish an odour threshold for hydrogen sulphide (Rotorua’s smell) is determining how high
levels have to be before people can detect them – a vital factor for geothermal projects as well as wastewater treatment
plants, waste transfer stations and composting operations.
No work has been done in New Zealand on this type of odour detection and local assessments have previously been based on
international measures rather than local conditions. The project has already tested a panel of people living in
different areas, including Rotorua, and assessed statistical data to be used in determining how much gas can be
detected.
Another project, proposed by Rivers and Drainage manager Bruce Crabbe, has investigated using dairy farm effluent to
feed fish species for commercial production, or replenish native fish stocks. A season of converting effluent to an
edible food source has been completed in tank trials, and whitebait have been successfully fattened on dairy effluent.
On-farm trials are planned this year.
Pollution Prevention officer Sam Weiss has been testing his wastewater treatment system which is designed to be
retrofitted to existing onsite conventional septic tanks, and meet permitted wastewater treatment standards in the
Regional Council’s On-Site Effluent Regional Treatment Plan.
The system was tested at the Rotorua National Testing Programme and complies with standards set in the regional plan. Mr
Weiss has been working with a manufacturing company to cost out manufacture and installation, estimated to be about
$11,000. An on-site trial of the system has not gone ahead as costs are similar to other systems already available.
Regional Council Corporate General Manager Brian Trott said the projects staff have come up under the Bright Ideas
scheme with have been exciting and innovative.
“Our staff are working out in the field every day around our region and can come up with better ways of doing things
using their experience and expertise. The Bright Ideas Innovation Fund provides a bit of a boost to give them the time
and some funding to get their ideas off the ground, and benefit the region’s communities,” he said.
“We’ve been excited to see the variety of projects staff have thought of – they’re often the kind of things academic
researchers might never come up with, and they have practical application in their everyday work.”
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