DEPARTMENT OF ENVIRONMENTAL QUALITY

DIVISION OF WATER AND RADIOLOGICAL PROTECTION

OUTHOUSES

(By authority of Act No. 273 of the Public Acts of 1939, being §325.271 of the Michigan

Compiled Laws)

R 325.421 Principles.

Rule 1. All "outhouses," buildings or other structures which are not connected with a

sewerage system or with a properly installed and operated sewage disposal system, and

which are used for the reception, disposition or storage, either temporarily or permanently,

of feces or other excreta from the human body, shall be constructed and maintained in such

manner as to conform at all times to the following:

(a) The receptacle for receiving and storing fecal matter shall be fly-tight and constructed

in such manner and of such material as to afford reasonable assurance of remaining fly-

tight under ordinary conditions of usage.

(b) The receptacle shall be so located as to prevent the pollution of private and public

water supplies, lakes or streams; the overflow of the contents to the surrounding ground;

and the flow of surface water into the receptacle. The receptacle should be convenient and

accessible to use.

rapid deterioration, to provide adequate capacity, and to facilitate maintenance in a

satisfactory manner under ordinary conditions of usage.

(d) The outhouse receptacle should be vented so as to provide a continuous escape of

odors through a screened vent.

(e) The outhouse shall be so maintained as to fulfill the foregoing principles at all times.

History: 1944 AC; 1954 AC; 1979 AC.

R 325.422 Minimum standards for earth-pit outhouses.

Rule 2. (1) The pit should be located 100 feet or more from any well or other source of

water supply and upon ground sloping away from the water supply, and should never be

located less than 50 feet therefrom, unless upon special approval of the commissioner of

the Michigan department of health; provided, however, that no pit shall be located within

200 feet of any source of groundwater used for a municipal water supply. No pit shall be

located less than 2 feet from any lot or alley line or less than 25 feet from any lake or

stream. In areas underlaid by limestone, or where fissured rock formations are common, or

whenever groundwater is encountered in the construction of the pit, approval of the

construction and location of the pit based upon special investigation of the conditions must

be obtained from the commissioner of the Michigan department of health.

(2) The pit shall have a capacity of not less than 50 cubic feet per seat and be not less than

4 1/2 feet or more than 6 feet deep, measured from the original ground surface. Where rock

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formations or groundwater are encountered at shallower depths, a mound may be

constructed to permit a pit of sufficient depth.

(3) Sills shall be provided to form the support for the outhouse building. Pit curbings shall

extend to the full depth of the pit unless in rock formation, in which case the lower section

of the curbing may be omitted. The curbing should not support the building or the sills.

(4) Pit mounds shall be of well-tamped earth installed in thin layers, shall extend outward

on the level for a distance of not less than 18 inches in all directions from the sills, and

thence outward to meet the surrounding ground surface with a slope not greater than 1

vertical to 3 horizontal. Mounds should be covered with sod or otherwise protected against

erosion.

(5) The floor and seat riser shall be built of impervious material or tongue and groove

lumber, and in a manner to exclude insects. The seat riser shall be so constructed and

bonded with the floor as to prevent seepage through the riser onto the floor.

(6) The seat opening shall be covered with a hinged lid.

(7) The pit should be ventilated from the riser to a point outside the building by a flue or

vent having a cross-sectional area of not less than 12 square inches. The joints shall be tight

and the opening screened with 16 mesh screening, preferably of copper.

History: 1944 AC; 1944 ACS 7; 1954 AC; 1979 AC.

R 325.423 Minimum standards for septic tank privy or septic toilet.

Rule 3. (1) The tank should be located at least 50 feet from any well or other source of

groundwater supply and upon ground sloping away from the water supply. No tank shall

be located less than 2 feet from any lot or alley line or less than 25 feet from any lake or

stream.

(2) The tank shall be constructed of an impervious material and be watertight. The depth

below the outlet pipe shall be not less than 30 inches. When constructed of concrete the

side walls, top and bottom shall be of a mixture and thickness which will insure a dense,

watertight structure. Sufficient reinforcement shall be used to prevent cracking. When

constructed of metal, Armco ingot iron or other rust-resisting material not less than 12

gauge shall be used. All metal surfaces inside and outside shall be thoroughly coated with

a good quality asphalt base material. All tanks shall be provided with an outside opening,

not less than 12 inches in diameter, fitted with a tight cover, to permit inspection and

cleaning. The outlet of all tanks shall be so constructed as to prevent solid material passing

into the discharge pipe. Tanks should be filled with water before being put into operation

and after each cleaning.

(3) A drop tube, securely fastened to the toilet bowl and to the tank, shall extend into the

tank but not more than 2 inches below the water line. A vitreous china toilet bowl with seat

and seat cover securely hinged should be used.

(4) A ventilating pipe connected to the bowl and extending above all parts of the building

shall be installed.

(5) Cast-iron soil pipe shall be leaded or bonded to the tank and extend not less than 10

feet from the building where it may be connected to the disposal tile. Disposal tile should

be laid so that a 12-inch earth cover is provided. Under no condition shall the tile line be

laid below the groundwater level.

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History: 1944 AC; 1944 ACS 7; 1954 AC; 1979 AC.

R 325.424 Minimum standards for chemical closets.

Rule 4. (1) The tank should be located at least 50 feet from any well or other source of

groundwater supply and upon ground sloping away from the water supply. No tank shall

be located less than 2 feet from any lot or alley line or less than 25 feet from any lake or

stream.

(2) The tank shall be constructed of Armco ingot iron or other rust-resisting material, not

less than 12 gauge thickness. All metal surfaces inside and outside shall be thoroughly

coated with a good quality asphalt base material. All tanks shall be provided with an outside

opening, not less than 12 inches in diameter, fitted with a tight cover, to permit inspection

and cleaning. Every chemical closet tank shall be equipped with an agitating device

designed to insure complete mixing of the organic matter with the chemical.

(3) The drop tube shall be securely fastened to the tank and to the toilet bowl. The toilet

bowl should be of vitreous china, designed to provide for a seat and seat cover.

(4) A ventilating pipe connected to the bowl and extending above all parts of the building

shall be installed.

History: 1944 AC; 1944 ACS 7; 1954 AC; 1979 AC.

R 325.425 Minimum standards of maintenance.

Rule 5. (1) The receptacle of an earth-pit or vault-type outhouse shall not be allowed to

fill to a point higher than 12 inches below the under surface of the floor of the outhouse

building. When the receptacle is filled a new pit should be provided and the floor and

building moved to

the new location. The receptacles of other types of outhouses shall be emptied at

sufficiently frequent intervals to prevent the creation of an insanitary condition.

(2) All fecal material or other excreta from the human body that has been removed from

any outhouse shall be buried with an earth covering of at least 12 inches in thickness and

in a location more than 200 feet from any domestic water supply, lake or stream. Feces or

other excreta from the human body shall not be deposited in any abandoned or dry well.

(3) The seat, floor, and ground immediately surrounding the outhouse shall be kept clean

at all times. The vent shall be maintained in good repair and free from obstructions at all

times.

(4) Seat covers shall be kept closed when the outhouse is not in use.

(5) No disinfectants, lime, deodorants, or other chemicals should be used in earth-pits,

septic tank privies or septic toilets. Chemical closets should be maintained at such caustic

concentration that septic action does not begin.

(6) Types of paper which do not readily disintegrate should be avoided. Garbage, ashes

and other kinds of wastes or liquids should not be thrown into earth-pits or tanks.

(7) Enough water should be added to the septic tank privy or septic toilet each day to keep

the water up to the level of the overflow. The water added should also be used to keep the

drop tube clean.

History: 1944 AC; 1954 AC; 1979 AC.

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