Biodesign
2026
Poddy
A microbial pod that turns portable-toilet waste into compost instead of chemical sludge.
Top 8 Finalist, Biodesign Challenge 2026
Platinum Medal Recognition for Narrative, Concept, Context & Reflection
Type
Microbial Sanitation System
Context
Biodesign Challenge 2026
Team
Team of Seven
Recognition
Top 8 Finalist
Biodesign Challenge — SCAD 2026
About Poddy
Poddy reimagines portable toilets by engineering the microbial ecosystem inside the tank rather than relying on harsh disinfectant chemicals. Instead of killing all bacteria and producing toxic, hard-to-treat waste, it introduces targeted microbial cultures that break down waste, reduce odor, and begin composting on-site.
Designed for high-use environments like festivals and national parks, the system improves sanitation efficiency, reduces environmental impact, and transforms human waste into a safer, more usable compost stream instead of landfill material.
Inside the pod
PHA gyroid lattice: a biodegradable scaffold, naturally produced by microorganisms, that sinks and shelters the culture as it expands.
Alginate membrane: a marine-derived film that dissolves quickly, releasing dye and exposing the bacteria.
Freeze-dried bacteria gel: Bacillus, Nitrosomonas and Thiobacillus cultures that neutralize H₂S and break solids into a stable bio-slurry.
Dyes, enzymes and fragrance: the familiar cues service crews and users expect, without the toxic chemistry.
The Problem
Toxic chemical additives prevent natural decomposition, turning portable-toilet waste into a hazardous liability that has to be landfilled rather than repurposed.
250,000 lbs of solid waste went into portable toilets during the NYC Marathon.
2 million gallons of toxic sewage are generated over the Coachella and Stagecoach festival season.
9.6 billion gallons of portable-toilet waste are produced worldwide every year, from 3.6 million units.
Field research
We visited Southeastern Sanitation in Savannah to learn from the crews who service these units every day. Local wastewater plants are actively rejecting chemically treated waste, and barrels of cleaning agents are clogging up the facility.
Poddy was validated to fit their high-speed workflow and existing logistics, and composting proved achievable with a low-cost process that spins the material and separates out the solids that still need landfilling.
Empty chemical barrels
The System
Pods ship in bulk, drop into the tank at every service, digest the waste in place, and leave the site as compost feedstock instead of sewage.
How it works
Breach: the alginate film dissolves, releasing dye and exposing the culture.
Scaffold: the PHA lattice sinks and shelters the bacteria as they colonize it.
Digest: microbes activate, neutralize H₂S and break solids down into a stable bio-slurry.
Verified zero-waste
We wouldn’t just hope it’s composted; we’d guarantee it. A digital chain-of-custody network tracks every load from the festival to the farm, giving events certified landfill-diversion data.
The result: complete landfill diversion and verified zero-waste sanitation for massive events.
Usage Map
PHA Gyroid Lattice
Team
Amelia Massetti, Josh Santiago, Brendan Sapp, Matteo Bariana, Camryn Claunch, Grace McCormick, Carter Spainhour
Platinum Medal Recognition for Narrative, Concept, Context & Reflection
