WASTEWATER FORESTS:

    Carbon Sequestration and Oxygen Generation utilizing Redwood Trees

Copyright © 2006   Ed Burton Company,  ebc@saber.net

Purpose and Objectives

We present this technical report of a proposed effluent disposal system utilizing,

	Final wastewater from a waste-treatment plant stored in a pond.
	Buried K-6 Eco-Chambers which disperses this nutrient-rich water to the roots.
	A Redwood plantation which acts as a nutrient pump to evapotranspire purified water and oxygen while sequestering CO2 into tree and root biomass.

Executive Summary

The following development plan provides a complete description of a wastewater disposal plan which augments an existing waste treatment plant.  It does not address the existing systems for collection, treatment, storage and disposal.  It does however offer a solution that can be transferred to other waste treatment facilities in other counties, the State, and other countries.  In short we are taking wastewater (a pollutant) and are using it as the nutrient solution for growing vibrant forests.

Facility Overview

We are increasing the capacity of existing waste treatment facilities by converting the existing surface-spray irrigation fields to a subsurface infiltration/evapo-transpiration (ET) redwood plantation.  Effluent will be delivered to the tree root zone by K-6 EcoChambers described later herein.  Capacity will be increased by two mechanisms. 

In the longer term: capacity will steadily increase concurrent with tree growth.

In the short term:  as subsurface dispersal is not so inhibited by inclement weather, as is surface spray disposal, significant winter dispersal will occur except during precipitation events that generate surface runoff.

Our analysis will demonstrate the anticipated growth curve of the trees and the related evapo-transpiration (ET) capacity.

System Description

Treatment plant effluent, (tertiary water) will be pumped directly from a holding pond to the forest dispersal field.   The pump-run timer will be set to provide a dose volume matching the storage volume of the K-6 EcoChambers.   The pump cycle timer will be set to provide the number of doses each day dependent upon seasonal transpiration rate of the forest.

An existing holding pond will be utilized for effluent storage when flows exceed evapo-transpiration (ET) capacity of a Redwood plantation.  We expect that the pond will initially receive significant effluent; with storage requirements decreasing as the Redwood plantation grows.

Effluent Flows

Effluent flows for this analysis are based on 5,000 gallons per day per acre and a final build out of 7,500 GPD/acre to support a Redwood plantation.  In the works are plans to develop 400 acres of forestry plantation supporting 3 million gallons of waste water per day.  There are several variables to consider including the sandy and loamines of the soil and its ability to absorb water.

Solar Powered Redwood plantation year 2

The Forest Transpiration and CO2 Sequestration System

To be effective in wastewater effluent disposal the species planted in the Forest Evapotranspiration System must transpire year-round and be tolerant of wide variations in soil moisture, especially excesses.  Coast Redwoods (Sequoia Sempervirens) are highly suited for these purposes.  Minor plantings of Mountain Redwoods (Sequoiadendrum Gigantea) will also be included.  We recommend the initial planting be denser than the ultimate density to maximize early capacity and allow for die-off and thinning.  For optimal growth and healthy forest management, thinning will be required as the trees mature.

Redwood trees are giant nutrient pumps that lift water out of the ground and convert carbon dioxide into biomass while giving off oxygen and transpiring pure water vapor. The capacity of a mature individual redwood tree to transpire water has been reported to be as high as 500 gallons per day (Hewes, 1981).   The ability to sequester CO2 is likewise prodigious and will be quantified later in this report.

The Specified K-6 EcoChambers

The K-6 EcoChambers are manufactured by the EBC Company of Willits, California.  Each K-6 is made of a section of plastic pipe (PVC or HDPE) 12 inches in diameter and 30 inches in length.   Unit volume is 2 cubic feet or 13 gallons. 

Both ends are closed by a perforated diaphragm, and perforations are plugged with “decorticated” redwood bark which allow the effluent to wick out to the tree roots. Several advantages accrue to the K-6 as compared to infiltration trenches, overland flow and spray irrigation.   Water is delivered to the soil without physical impact or flooding, only at the rate at which the soil and trees can assimilate it.

Matting of surface vegetation due to excessive overhead wetting is avoided along with the sealing of the soil surface caused by decaying vegetation.  Silt sealing of the soil surface from impact of energy droplets is avoided by subsurface application.  Subsurface application creates no human or animal contact with surface ponding, runoff, and aerosols.

At ten foot intervals K-6s are buried eighteen inches deep.  A tree is planted over each of the infiltrators.  The infiltrators fill with wastewater which passes through  the root zone of the trees.   The trees send feeding roots toward the infiltrators as their source of nutrients and water.  Solid pipes carry wastewater from one infiltrator to another.

Floating Eco-Chamber Rafts

Capacity Analyses and Water Balance

Using a sample of a Wastewater Dispersal and Redwood Forest Evapotranspiration System that was planted in 1979,  the following can be disclosed

           Year               Tree Age- Years    Water Use GPD/Tree

The trees had more than quadrupled their average height in 7 years, from 5 feet at planting in January 1979, to 23 feet in 1986.

We will show that carbon sequestration rates, while different than evapotranspiration rates,  are similar in their scale as the tree matures.  The water in the tree is a transport system for minerals which are converted into cellulose, plant sugars, and the release of oxygen.

Solar Powered Zero Discharge Wastewater Sequester and Redwood Seedling Nursery

Conclusion:

We have shown that a pollutant like waste sewage water can be made into a nutrient rich resource to water a Redwood Plantation.   This is very important because towns and cities all over the world are overflowing with wastewater.  Every flush all over the world is composed of 3 to 5 gallons of our drinking water.   This multiplied by 2 to 4 billion flushes per day, and one gets the idea of the dimension of this problem.

As we explore solving the problem of global warming and the sequestering of greenhouse gases, we come to the conclusion that what we need most is water to water the millions of trees that have to be planted and sustained.   Nutrient rich wastewater is the answer.  The waste of one process becomes the food of the next process.   These are one of the tenents of ecological design.   This is also the slogan of Ed Burton Company.  Turning waste into products.

We will now deal with the uptake potential of Redwood trees to sequester carbon dioxide and to generate pure oxygen and water.