(A) All sanitary sewer systems (lying in these areas of the S.O.C.S.D.S. district, designated as separated) to be connected directly or indirectly into the intercepting sewer or sewers of the S.O.C.S.D.S. prior to connection, shall meet the following requirements:
(1) A connection permit shall be obtained by the owner or contractor from the Oakland County Drain Commissioner's Office. The connection permit shall show the location of the work, the extent of the work, information regarding the contractor, the owner and the engineer, the scheduled date of infiltration test and any other pertinent information as shall be determined necessary by the Oakland County Drain Commissioner. A fee shall be charged for said permit to cover the cost of inspection of the connection and system connected.
(2) All sewer systems shall be subjected to infiltration, air, or exfiltration tests or a combination thereof in accordance with the following requirements prior to acceptance of the system by the Oakland County Drain Commissioner's Office.
(a) Infiltration test. All sewers over 24-inch diameter shall be subjected to infiltration tests. All sewers of 24-inch diameter or smaller where the ground water level above the top of the sewer is over seven feet shall be subjected to an infiltration test.
(b) Maximum allowable infiltration shall not exceed 250 gallons per inch of diameter per mile of pipe per 24 hours for the overall project. Maximum allowable infiltration shall not exceed 500 gallons per inch of diameter per mile of pipe per 24 hours for any individual run between manholes.
(c) Air test or exfiltration test.
1. All sewers of 24-inch diameter or less, where the ground water level above the top of the sewer is seven feet or less, shall be subjected to air tests or exfiltration tests.
2. For exfiltration tests the internal water level shall be equal to the external water level plus seven feet as measured from the top of pipe. The allowable exfiltration rate shall be the same as that permitted from infiltration.
3. The procedure for air testing of sewers shall be as follows:
a. The sewer line shall be tested in increments between manholes. The line shall be cleaned and plugged at each manhole. Such plugs shall be designed to hold against the test pressure and shall provide an airtight seal. One of the plugs shall have an orifice through which air can be introduced into the sewer. An air supply line shall be connected to the orifice. The air supply
line shall be fitted with suitable control valves and a pressure gauge for continually measuring the air pressure in the sewer. The pressure gauge shall have a minimum diameter of 3½ inches and a range of 0 - 10 PSIG. The gauge shall have minimum divisions of 0.10 PSIG and an accuracy of ±0.04 PSIG.
b. The sewer shall be pressurized to 4.0 PSIG greater than the greatest back pressure caused by ground water over the top of the sewer pipe. At least two minutes shall be allowed for the air pressure to stabilize between 3.5 and 4.0 PSIG. If necessary, air shall be added to the sewer to maintain a pressure of 3.5 PSIG or greater.
c. After the stabilization period, the air supply control valve shall be closed so that no more air will enter the sewer. The sewer air pressure shall be noted and timing for the test begun. The test shall not begin if the air pressure is less than 3.5 PSIG, or such other pressure as is necessary to compensate for ground water level.
d. The time required for the air pressure to decrease 1.0 PSIG during the test shall not be less than the time shown in the “Oakland County Drain Commissioner's Air Test Tables.”
e. Manholes on sewers to be subjected to air tests shall be equipped with a 1/2 inch diameter galvanized capped pipe nipple extending through the manhole, three inches into the manhole wall and at an elevation equal to the top of the sewer pipe. Prior to the air test, the ground water elevation shall be determined by blowing air through the pipe nipple to clear it and then connecting a clear plastic tube to the pipe nipple. The tube shall be suspended vertically in the manhole and the ground water elevation determined by observing the water level in the tube. The air test pressure shall be adjusted to compensate for the maximum ground water level above the top of the sewer pipe to be tested. After all tests are performed and the sewer is ready for final acceptance, the pipe nipple shall be plugged in an acceptable manner.
(3) If a sewer fails to pass any of the previously described tests, the contractor shall determine the location of the leaks, repair them and retest the sewer. The tests shall be repeated until satisfactory results are obtained.
(4) All visible leaks and cracks shall be repaired regardless of test results.
(B) Storm and ground water control. Yard drains, patio drains, catch basins, downspouts, weep tile, perimeter and footing drains or any other structure used for the collection and conveyance of storm water and/or ground water shall not be permitted to discharge into any sanitary sewer connected directly or indirectly to the county system, except as provided below:
(1) Perimeter and footing drains from buildings existing before July 23, 1981 shall not be required to disconnect from the sanitary sewer system, provided that federal, state or local law or regulation does not require, or may not require subsequent to the adoption of these standards and regulations, the disconnection of such perimeter and footing drains.
(2) The crock to iron joint shall be sealed by approved flexible adaptor fittings such as those manufactured by Fernco Joint Sealer Company, or as approved by the Oakland County Drain
Commissioner's Office. The iron pipe inside the building shall be plugged and leaded and remain plugged and watertight until such time as the plumbing is carried on to the first floor, the basement backfilled and the roof is on the building, thereby providing that no water from the excavated basement will enter the sanitary sewer.
(C) Building sewers.
(1) House connection sewer from lateral sewer in the street or easement five feet from house shall be:
(a) Six-inch diameter Extra Strength Vitrified Sewer Pipe, manufactured in accordance with current NCPI Designation ER 4-67 Standards, or equal, with Drain Commissioner approved premium joint, or
(b) Six-inch diameter ABS Plastic Solid Wall Sewer Pipe conforming to ASTM designation D-2751 SDR 35 or 23.5, or
(c) Six-inch diameter PVC Plastic Solid Wall Sewer Pipe conforming to ASTM designation ASTM D-3034 SDR 35 or ASTM D-2665 Schedule 40.
(d) Other pipes and joints as may be approved by the Oakland County Drain Commissioner.
(2) House connection sewers should be six-inch minimum diameter; however, four-inch pipe of comparable strength and joint material may be used if permitted by the local unit of government. All joints shall be tight and when tested for infiltration, shall not exceed 500 U.S. gallons per inch of diameter, per mile, per 24 hours.
(3) The crock to iron joint shall be sealed by an approved bituminous filler, enclosed in concrete to provide a watertight seal. The iron pipe inside the building shall be plugged and leaded and remain plugged and watertight until such time as the plumbing is carried on to the first floor, thereby providing that no water from the excavated basement will enter the sanitary sewer.
(4) The municipality shall issue tap permits for each structure that is connected into the S.O.C.S.D.S. and be responsible to see that the above specifications pertinent to materials and installations are followed.
(D) The S.O.C.S.D.S., through their agent, the Drain Commissioner, shall, at his option, be permitted to set up and operate flow metering equipment to gauge sanitary flow, either on a temporary or permanent basis, in any sanitary sewer lying within the said “separated areas.”
(E) Plans and specifications covering the construction of all new sewers, both combined and sanitary (separate), lying within the S.O.C.S.D.S. service area shall be submitted to the Office of the Oakland County Drain Commissioner for review and approval prior to construction.
(F) The quality of domestic and industrial waste outletted into the S.O.C.S.D.S. facilities shall conform to the current city of Detroit ordinance pertinent to domestic and industrial wastes. It is the contractual obligation of the municipality, reference Section 16 of contract with county, to use S.O.C.S.D.S. facilities to enforce these standards.
(G) No requirements of the S.O.C.S.D.S. or permits issued hereunder by said system through their agent, the Oakland County Drain Commissioner, shall relieve the property owner of complying with all the rules and regulations of the local unit of government, wherein such property is located, where such are not in conflict with requirements of the S.O.C.S.D.S.
(H) All sewer construction shall comply with the general specifications of the Oakland County Drain Commissioner; copies of said specifications may be obtained from the Office of the Drain Commissioner.
(Ord. 23.27, passed 1-8-90)