Annapolis River - Sunscreen
Wastewater is cleansed by the sun
The Annapolis River bulges and swells into the Annapolis Basin before surrendering
its waters to the sea. The basin is a collector of pollution from the Annapolis
River and its tributaries.
An innovative effort to stop the flow of pollution into the basin is being made
by the Mi'kmaq community of Bear River. This river shares the Annapolis Basin
with the Annapolis River. In this community, the first greenhouse sewage treatment
plant in Canada uses sunlight, plants, and fish to purify wastewater from homes
From the outside, the sewage plant looks like an ordinary greenhouse. Inside,
there is a series of transparent tanks, a pond, and an artificial marsh containing
a variety of algae, water plants, snails, and fish.
First, solid items are filtered from the raw sewage which is then directed to
an underground blending tank. Bacteria is added and air bubbled through the sewage
to accelerate natural decomposition.
The wastewater is then pumped into the greenhouse. In the clear tanks, microscopic
plant forms, including algae and zooplankton, use the energy they absorb from
sunlight to digest nutrients in the wastewater. Snails also live in the tanks
consuming organic matter.
The sewage then passes through the pond and marsh where bigger plants and fish
consume the remaining nutrients.
The process of consuming organic matter in sewage converts the sewage to plant
and animal growth, heat, carbon dioxide, and clean water. Solid particles and
the plant life are collected for use as soil compost and fertilizer.
The water flowing out of the system is perfectly clear. It is disinfected by
ultraviolet light before being released into the Bear River estuary of the Annapolis
Basin. What is most distinctly innovative about the Solar Aquatics™ plant
at Bear River is the fact that not a single chemical is ever added to the wastewater
at any stage of the treatment process.
River (Adobe PDF document) Rivers
of Canada (All pages in a zipped file)