A trial to use maggots to reduce the amount of food waste filling bins

June 23, 2024 9:47 PM

Food scraps make up about a third of general waste bins. City of Sydney hopes maggots can help reduce this and turn it into fertiliser. A 12-month trial using Goterra's black soldier fly larvae system will begin with hopes it can be extended to all Sydney residents.
posted by chariot pulled by cassowaries (15 comments total)

My local council is one of the 4 councils in Sydney participating in this program, and I think it's great. It's significantly reduced what I put into landfill.

However, the local facebook community group is wall to wall with boomers who are mad that they have do things slightly differently.
posted by His thoughts were red thoughts at 10:19 PM on June 23 [1 favorite]

However, the local facebook community group is wall to wall with boomers who are mad that they have do things slightly differently

Yes, it was the same here when my council got FOGO bins - Food Organics, Garden Organics - the organic waste gets forcibly aerated with powerful electric blowers at the tip site, the idea being that

a) it reduces methane output (methane being much more potent per kilogram towards climate change than C02 per kilogram)

b) the resulting compost can be sold and used on people's gardens.
posted by chariot pulled by cassowaries at 10:24 PM on June 23 [3 favorites]

What could possibly go wrong? A mentor of mine was in charge of the project to eradicate the screw-worm Cochliomyia hominivorax from Africa by dispersing irradiation-sterilized males across the Libyan desert. The larvae were hatched in Mexico and air freighted to Benghazi via Frankfurt. If the timing was right, and this depended on quite precise temperature control throughout the process, the SIT (Sterile Insect Technique) blow-flies could be dumped out of small airplanes as they systematically criss-crossed the affected area. It all worked like clock-work, except when one flight was delayed and all the flies hatched out on the runway in Frankfurt. "covered in beeeees".

TFA says "black soldier fly larvae are changed every seven days" which shd be okay given that they are larvae for about 2x that time. For the record BSF are Hermetia illucens.

One of the last students I supervised was working on a similar compost-reduction project using red worms Eisenia fetida which may be less efficient at chomping food-waste but at least there's no chance of a blooming buzzing confusion when timing goes awry.
posted by BobTheScientist at 11:06 PM on June 23 [4 favorites]

I knew an Oz city who threw out some food
I don't know why they threw out the food
Perhaps they're screwed

I knew an Oz city who hatched out a fly
They hatched the fly to swallow the food
that decayed anaerobically under the ground
I don't know why they threw out the food
Perhaps they're screwed
posted by away for regrooving at 12:11 AM on June 24 [9 favorites]

Love to see composting as infrastructure. Our municipal composting accepts anything from meat to small tree limbs, which is wonderfully convenient but makes me wonder how the heck they manage that into a good material stream for composting. I'm interested in the tradeoffs between whatever they do, and biological systems like Eisenia or these insect larvae.
posted by away for regrooving at 12:18 AM on June 24 [2 favorites]

hot composting's a process stateside [deepgreenpermaculture]
posted by HearHere at 12:24 AM on June 24

I have had a backyard bin for about 15 years in different configurations, and soldier flies – which are native to where I am – always find their way in. Their larva are voracious and do a great job of compost breakdown. Also, the birds eagerly eat the adults.
posted by ryanshepard at 4:22 AM on June 24 [2 favorites]

...with hopes it can be extended to all Sydney residents.
I'm hoping this is extended to the garbage of the residents, but not the residents themselves.
posted by MtDewd at 7:54 AM on June 24 [1 favorite]

Well, I dunno, MtDewd; Seattles been windrow-composting our organic domestic waste for decades and now we can have our own corpses composted too . (DIFFERENT FACILITES.)

I didn’t get, in the article, why the pile-it-high-and-turn-it-over method doesn’t work for Sydney. Needs too much land? Weather wrong?
posted by clew at 9:22 AM on June 24 [1 favorite]

which is wonderfully convenient but makes me wonder how the heck they manage that into a good material stream for composting

All of the material is usually run through a grinder at the composing facility or some point in-between.
posted by Dr. Twist at 9:25 AM on June 24

I mean, if it's a choice between fertile soil and a zombie apocalypse...
posted by Halloween Jack at 9:26 AM on June 24

a good material stream

Specifically, it seems like the C:N ratio would have no reason to be workable, and might vary wildly between the season when your inputs are fresh grass clippings (from grass clipping collector people) versus dead leaves. Do they dump in guano for fall?
posted by away for regrooving at 12:03 AM on June 25

Specifically, it seems like the C:N ratio would have no reason to be workable, and might vary wildly between the season when your inputs are fresh grass clippings (from grass clipping collector people) versus dead leaves. Do they dump in guano for fall?

Very few Australian native trees are deciduous. Most Australian trees don't lose their leaves in Fall/Autumn, rather they shed their leaves constantly a bit at a time 365 days a year (with possible leaf shedding spikes due to extreme drought, or if strong winds/storms tear the leaves off.)
posted by chariot pulled by cassowaries at 5:12 AM on June 25 [2 favorites]

I'm so progressive, I had maggots in my bin twenty years ago!
posted by demi-octopus at 12:40 PM on June 25

I'm so progressive, I had maggots in my bin twenty years ago!

Yeah. I live in the Southeastern US and have big suburban roll out bins. This time of year they are as inevitable as the hot days.
posted by thivaia at 3:47 PM on June 25