CyclifierCyclifier

All Cyclifiers

A building or a spatial entity that enables or facilitates a new connection between excess and source flows.

Baima canal restorer

reviewed by RevigeMr

Short description

Ecological restoration in a sewage-filled canal with public space development.

Description

The Baima canal restorer by Todd Ecological is a case of ecological engineering in combination with the creation of public space. A city canal was polluted with the sewage of thousands of inhabitants, thus creating health, safety, and odor problems. John Todd installed a linear restoration element in the canal that aerates and supports the growth of aquatic plants that take up nutrients to counter the eutrophic effects of sewage. Along the growth-supports, there was also built a new pedestrian transportation route. 

Sources

  • toddecological.com

Data

Phase:

Decommissioned

Starting date:

01-01-2002

Lifespan:

Scale:

District

Qualitative Analysis

Description of the Process

Wastewater entering the end of the canal is re-cycled to the top of the canal for treatment. An anoxic zone at the top of the canal allows for denitrification. The fine bubble aeration system distributes air along the canal from blowers locat- ed on a central floating barge. Low-intensity and uniformly distributed aeration circulates the water while forcing it past biologically active zones. The Restorer automatically inoculates the system with beneficial bacteria at two locations. A variety of bacteria species were selected specifically for their ability to aid in sludge and grease digestion as well as nitrogen removal.

Situation before

The City of Fuzhou’s wastewater issues are typical of many developing world cities. The odors from the Baima Canal in particular were a major issue with adjacent temples, elementary school, and many residential apartment buildings. A 600-meter canal named Baima, considered one of the worst in the city, had extreme problems with odor and floating solids created by the influx of 750,000 gallons per day of untreated domestic sewage.

History

Rather than re-piping the polluted water to a remote wastewater treatment facility, the city government sought an affordable and low maintenance treatment system within the canal itself. In 2002, John Todd Ecological Design collaborated with Ocean Arks International to design a 500-meter linear Restorer for their Chinese partners on the Baima canal using 12,000 plants composed of 20 native species. Constructed with a walkway down the center, the Restorer has met water quality goals and created a prized recreation area for the members of the community. The plant root zones and fabric media of the Restorer provide biophysically diverse surface areas necessary for effective biological treatment of wastewater.

Result of project

The Restorer system succesfully met the goals set by the City of Fuzhou. The Restorer was able to reduce odors, eliminate floating solids, and drastically improve the asthetics of the neighborhood. Furthermore this technology reduced the negative impact of the pollutants in the canal on downstream aquatic ecosystems. The clarity of the water in the canal increased from less than 6 inches to several feet, while meeting several secondary effluent standards.

Role of different stakeholders in the system during the realization and maintenance of the project

The project was eventually decommissioned due to the dredging lobby in the city of Fuzhou. The Baima canal restorer was removed.

http://toddecological.com/
creative commons
alt Baima canal restorer
RevigeMr
  • The restorer hosts aquatic plants that extract nutrients from the water.
    creative commons
    Plantings on the restorer

    Plantings on the restorer

  • Baima canal with the addition of the restorer.
    creative commons
    Restoration element in the canal

    Restoration element in the canal

  • A sluice gate the canal before the restoration.
    creative commons
    Baima canal before situation

    Baima canal before situation

  • The pollution in the canal before the project.
    creative commons
    Baima canal before situation

    Baima canal before situation

Drawings

  • 3D Sankey Diagram

    2012architecten, Anna Brambilla Processes and actors are identified by labeled platforms with sub-processes shown as stacked platforms. The system boundary is shown as an extruded block indicating that it is one piece within a larger network. Starting from the edges of the cyclifier, distances are marked in intervals to indicate the distances traveled by inputs and outputs. Flows are scaled by mass as in sankey diagrams and are color-coded per flow type. Flows to and from the atmosphere are represented as traveling vertically.
    http://2012architecten.nl/
    Share-Alike
    3D Sankey Diagram