Part 1

Transcriber Note

Text emphasis denoted by Italics and =Bold=. Whole and fractional parts of numbers as 123-4/5.

U. S. DEPARTMENT OF AGRICULTURE

FARMERS' BULLETIN No. 1227

SEWAGE AND SEWERAGE OF FARM HOMES

DISPOSAL OF FARM SEWAGE in a clean manner is always an important problem. The aims of this bulletin are twofold--(1) to emphasize basic principles of sanitation; (2) to give directions for constructing and operating home sewerage works that shall be simple, serviceable, and safe.

Care in operating is absolutely necessary. No installation will run itself. Continued neglect ends in failure of even the best-designed, best-built plants. If the householder is to build and neglect, he might as well save expense and continue the earlier practice.

Washington, D. C. Issued January, 1922 Revised October, 1928

SEWAGE AND SEWERAGE OF FARM HOMES

George M. Warren, Hydraulic Engineer, Bureau of Public Roads

CONTENTS

Page

Introduction 1

Sewage, sewers, and sewerage defined 1

Nature and quantity of sewage 2

Sewage-borne diseases and their avoidance 2

How sewage decomposes 5

Importance of air in treatment of sewage 7

Practical utilities 8

Septic tanks 21

Grease traps 43

General procedure 45

INTRODUCTION

The main purpose of home sewerage works is to get rid of sewage in such way as (1) to guard against the transmission of disease germs through drinking water, flies, or other means; (2) to avoid creating nuisance. What is the best method and what the best outfit are questions not to be answered offhand from afar. A treatment that is a success in one location may be a failure in another. In every instance decision should be based upon field data and full knowledge of the local needs and conditions. An installation planned from assumed conditions may work harm. The householder may be misled as to the purification and rely on a protection that is not real. He may anticipate little or no odor and find a nuisance has been created.

SEWAGE, SEWERS, AND SEWERAGE DEFINED

Human excrements (feces and urine) as found in closets and privy vaults are known as night soil. These wastes may be flushed away with running water, and there may be added the discharges from washbasins, bathtubs, kitchen and slop sinks, laundry trays, washing vats, and floor drains. This refuse liquid product is sewage, and the underground pipe which conveys it is a sewer. Since sewers carry foul matter they should be water-tight, and this feature of their construction distinguishes them from drains removing relatively pure surface or ground water. Sewerage refers to a system of sewers, including the pipes, tanks, disposal works, and appurtenances.

NATURE AND QUANTITY OF SEWAGE

Under average conditions a man discharges daily about 3½ ounces of moist feces and 40 ounces of urine, the total in a year approximating 992 pounds. Feces consist largely of water and undigested or partially digested food; by weight it is 77.2 per cent water. Urine is about 96,3 per cent water.