19-09-2012, 04:37 PM
Soil Texture, Water & Septic Tanks Drain Fields
Texture, Water.ppt (Size: 3.18 MB / Downloads: 94)
Permeability – Water Transmission
Sandy soils will have fast water transmission and low water retention
Clay soil will have slow water transmission and high water retention.
Porosity and Permeability
Porosity is a measure of the open space within soil or rock
Pore spaces represent the reservoir for holding water.
Permeability is a function of the sizes of particles, pores, and the way they are arranged.
Permeability is how quickly water will flow through the soil
The straighter and larger the pores, the faster the permeability.
Clays tend to reduce the porosity and permeability of soil material due to the small pores.
Generally, surface horizons have a larger porosity and subsoils have smaller porosity and reduced permeability
Depth to Water Table
Many landscapes have soils that are going to be in contact with the water table.
Soils will show “Wet Soil” characteristics when they develop in this type of landscape position.
The depth to the water table is independent of soil texture.
Sewage Disposal
For cities and towns sewage is collected and treated in a waste water treatment plant.
The US has spent may billions of dollars upgrading and building these facilities to clean up our surface waters.
Some ocean communities still use ocean outfalls for their waste.
Septic Tank Systems
In rural areas not serviced by sewer systems, a method of disposal of common household and human wastes is necessary.
For these areas an anaerobic treatment process called a septic system is employed.
Alternative Systems
Traditional septic systems have proved to be an effective way to treat sewage when space and good soil conditions exist.
However -- When space is limited or soil conditions are poor, homeowners may need a modified treatment system.
Poor soil conditions include clay textures, soils that are poorly drained, soils shallow to bedrock or soils that are sand and too permeable.
Composting Units
Separating solid wastes from the toilet and delivering them to a composting unit reduces household water use up to 40 percent.
Composting removes many pathogens while nutrients are stored in the safe compost which can be used on the garden.
Some systems use worms, while others use bacteria and aeration. The composted material must be removed periodically.
Cost – $1200 -3000