While laying the pipe a stopper is used to prevent the sewer gases and foul odors from escaping. This stopper sometimes is of tile, sometimes a plug of paper or burlap. This stopper is sometimes cemented in by inexperienced men and the trouble created can only be guessed at. If a stopper is used, the workman must see that it is taken out.
REFILLING.--After the pipe is laid and cemented, it should be covered and allowed to stand 24 hours to give the cement time to harden. The dirt should then be thrown in and settled by means of a tamper or by flooding with water. The planks should not be taken out until the trench is well filled. To pull the plank, a chain or shoe and lever will have to be used. Where the tunnels are, dirt will have to be rammed in with a long rammer, care being taken not to disturb the pipe. If the refill is not well rammed and tamped, the trench will settle and cause a bad depression in the street surface.
TERRA-COTTA PIPE.--Terra-cotta pipe should be straight, free from fire cracks, and salt-glazed. The inside of the hub and outside of the plain end should not be glazed. This allows the cement to take hold.
TABLE OF STANDARD TERRA-COTTA PIPE
------+------------+-----------------+----------+-------------- Size Thickness, Weight per ft., Depth of Annular space inches pounds socket ------+------------+-----------------+----------+-------------- 3 1/2 7 1-1/2 1/4 4 1/2 9 1-5/8 3/8 5 5/8 12 1-3/4 3/8 6 5/8 15 1-7/8 3/8 8 3/4 23 2 3/8 9 13/16 23 2 3/8 10 7/8 35 2-1/8 3/8 12 1 45 2-1/4 1/2 15 1-1/8 60 2-1/2 1/2 18 1-1/4 85 2-3/4 1/2 20 1-3/8 100 3 1/2 ------+------------+-----------------+----------+--------------
Terra-cotta pipe should not be permitted in filled-in ground.
Roots of trees find their way into the pipe through cracks or cement joints. When the roots get inside of the pipe they grow until the pipe is stopped up. As the roots cannot be forced or wired out, the sewer must be relaid. The writer has seen a solid mass of roots 10 feet long taken out of a tile sewer.
In case terra-cotta is laid in filled-in ground, there is only one way to insure the pipe from breaking. The pipe should be laid on planks. Then, if the ground settles, the pipe will not be broken.
WATER CONNECTION AND SERVICE
TAPPING MAIN.--The water service for a building is put in at the same time as the sewer is connected and run into the house. For a 1-1/4-service pipe a 1/2-inch tap is furnished. The water company taps the main, at the expense of the plumber, and inserts a corporation cock.
[Illustration: FIG. 42.--Showing water main and sewer in same ditch.]
DIGGING TRENCH.--The trench for the water main should be dug at least 4-1/2 feet deep or below frost level and the trench should be kept straight. When the sewer is put in at the same time, one side of the sewer trench can be cut out after it is filled up to the level of the water main. The water pipe can then be laid on this shelf at least 2 feet away from the original trench of sewer.
Sometimes the surface of the ground must not be disturbed. In this case small holes are dug and the pipe is pushed through or driven through under that portion not dug. These places are often tunnelled (see Fig. 42).
In digging in city streets, care should be taken not to destroy any of the numerous pipes encountered.
LAYING PIPE
The trench should be dug straight out from the house so the pipe can be laid and the main tapped straight out from the building. The water companies keep a record of these taps so that in case of trouble the street can be opened and the water shut off. In laying the water service, the pipe from the curb to the main should be laid first. This takes in all the pipe in the street. At the main there is a shut-off in the tap. Another stop with T or wheel handle must be placed just inside the curb line. This is called a curb cock (see Fig. 43). One trench either outside or inside of the curb should be at least 15 feet long so that a full length of pipe can be laid in the trench. It is generally impossible to open a trench the full length the pipe is to be run. A trench 10 feet long is dug, then 8 feet left, and another 10- or 8-foot trench is dug and the two are connected with a small tunnel and pipe pushed through.
When the pipe has been put in place between the curb and main, the water is turned on and the pipe flushed out. The valve at the curb should now be shut off, and if there are any leaks they will show.
The street part is now ready to fill in. At this point Fig. 43 should be studied. Note the piece of lead attached to the pipe and corporation cock. This piece of lead should be extra heavy and always laid in place the shape of the letter S or goose neck. In case the street should settle, this piece of lead will allow for it. These "lead connections" or "goose necks" are made as follows: 3 ft. of 5/8 lead pipe; 1-inch brass solder nipple (wiped on); one brass corporation cock coupling (wiped on).
LAYING PIPE.--This lead connection can be screwed on the pipe after the pipe is laid, then bent and coupled on the main with the coupling.
[Illustration: FIG. 43.--Water main from street to foundation wall.]
After the pipe has been tested as far as the curb, the trench in the street can be filled as described later. The pipe from the curb to the building can now be laid. If necessary to push the pipe through a tunnel, the end of the pipe should first be capped. Start by screwing a length in the curb cock. If the other end of the pipe comes in a tunnel an additional length must be put on before putting in place so that an end will come in the open trench. When the building is reached and before the stop cock is put on, the valve at the curb should be opened full and the pipe flushed out.
The valve can then be put on and water turned on to test the pipe.
SETTING CURB BOX.--A cast-iron box, adjustable length, with cover should extend from the curb cock to the surface. This makes it possible with a long rod to control the water service into the building. To set a curb box some flat stones should be laid around the curb cock and the box set on these stones. Then the space around the box and pipe should be closed in with brick or other covering to keep the sand from washing in on the curb cock. The box should be adjusted for height and then held in place by placing the curb key rod in place and holding the rod and box while the trench is filled. The refill should be tamped evenly on all sides of the box.
REFILL.--In refilling the trench around the corporation cock and goose neck, the greatest care should be taken. The writer has seen cases when indifferent workmen have tossed heavy stones in the ditch and broken off the corporation cock or destroyed the goose neck. After the pipe is covered with 18 inches of refill and tunnels have been filled, water can be run in the trench and will settle the refill.
There are a number of special points concerning water services and taps at mains that should not be overlooked. Take for example a water service pipe which must be run through ground where electricity is escaping under trolley tracks, around power houses, etc. The electricity will enter the pipe and wherever it leaves the pipe a hole is burned. The surface of the pipe in a short time will be full of small pith marks and will soon leak. A good way to add to the life of the pipe under these conditions is to make a star of copper and solder it on to the pipe in the street. Another piece of copper should be put on the pipe near the building. The electricity will leave the pipe by way of the points on the star. This method may not be a cure for electrolysis, but will add to the life of the pipe. Another method employed is to put the pipe in the center of a square box, then fill the box with hot pitch. When this is hardened the pipe will have a covering that will keep out any moisture and bar electricity to a marked degree.
MATERIALS USED.--Galvanized steel pipe does not last under ground.
Galvanized iron, heavy lead, and brass are used. Wooden pipes were once used and stood years of service. No service smaller than 1-1/4 should be used.
When the water service pipe passes through the foundation wall, the pipe should not be built in, but a small arch should be built over the pipe or a piece of XX cast-iron pipe can be used as a sleeve (Fig. 44).
[Illustration: FIG. 44.--Free space around pipe passing through wall.]
POINTS TO REMEMBER.--
SEWER INSTALLATION
_First_, select good sound pipe and fittings.
_Second_, locate branch connection in street sewer.
_Third_, lay out run of house sewer.
_Fourth_, take out necessary permits from departments of sewer.
_Fifth_, dig trench in the street, then into the house.
_Sixth_, lay pipe and cement joints.
_Seventh_, refill trench, tamping every foot.
_Eighth_, cast-iron pipe for sewer is found under another heading.
WATER SERVICE
_First_, take out necessary permits.
_Second_, list material and deliver to job.
_Third_, lay out and dig trench.
_Fourth_, have main tapped.
_Fifth_, lay pipe to curb and test.
_Sixth_, fill in street trench.
_Seventh_, lay pipe into building and test.
_Eighth_, set curb box.
_Ninth_, refill trench.
_Tenth_, thoroughly consider any special conditions.