City Earth Tub Composting System

The Earth Tub Composting Program

In 2017, the Arcata City Council adopted the Zero Waste Action Plan (ZWAP). The 10-year plan outlines eight implementation goals to help guide Arcata towards zero waste. One of these goals specifically addresses reducing food and other organic waste. To help divert organic waste from ending up in the landfill, the City of Arcata purchased two composting vessels called Earth tubs.Earth Tub Design Overview

The Earth Tub is a closed vessel composting system manufactured by Green Mountain Technologies.  It was chosen due to its size, design, cost, and relative success over at Cal Poly Humboldt. The Earth Tub eliminates any odors associated with composting thanks to its aeration and bio-filtration components. It also keeps out vectors such as rodents. The Earth Tub has a 3 cubic yard capacity and can receive up to 500 lbs of food waste per day. The City's Earth Tubs are conveniently located at Bayside Park Farm & Community Garden and are managed by the Environmental Services Department. When the Earth Tub is ready to be harvested, the finished compost will be used for landscaping and farming purposes. 

Piloting the Program

The Earth Tub composting program is currently in its early stages. Installation began in late 2018, and operation began in February 2019. The composting program consists of collecting compost bins from various city facilities, programs, and events. The goal is to eventually incorporate compost collection wherever food waste is generated on city property.

The following City facilities and programs are currently diverting their organic waste to the City's Earth Tubs:

Dual Tubs

The City's Earth Tubs are located at Bayside Park Farm and Community Garden

Single Tub
Single earth tub
Biofilter material
Bio-filters are absorbent beds of porous organic materials containing microorganisms that break down odorous compounds.
Biofilter

The aeration system consists of a perforated center post which allows air into the base of the compost and the bio-filter blower which creates negative pressure at the top of the tub.