Rust and dirt in water pipes are more or less successfully removed as follows: Tie a piece of small, stout cord to each end of a 2-foot length of small chain. Each piece of cord should be a little longer than the length of pipe to be cleaned. Attach the free end of one of the cords to a stiff steel wire and push the wire and cord through the pipe. By means of the cords pull the chain back and forth through the pipe, and then thoroughly flush the pipe with clean water under strong pressure. Long lines may be opened at intervals and cleaned section by section.

Other methods are: Using a swab or wire brush attached to a small steel or brass rod; flushing with a powerful hand pump; or filling the pipe with diluted muriatic acid and allowing it to stand in the pipe long enough for the acid to act. If the treatment is unsuccessful it should be repeated. A mixture of 1 part of acid and 7 parts of water allowed to stand overnight in 1,000 feet of badly rusted 1-inch pipe has given good results. After the acid treatment the pipe should be flushed long and thoroughly with clean water to remove as fully as possible all dirt, rust, and traces of acid.

When new piping is put in, abrupt turns are sometimes made with T branches instead of elbows. The unused leg of the branch can be closed with a screw plug, thus permitting easy access to the interior of the pipe.

Caution: When a stop and waste (or valve) on a water service is closed to permit cleaning or repairs, care should be taken to prevent the formation of a vacuum in the high parts of the water piping and the connections to plumbing fixtures; otherwise siphon action may draw pollution from water closets having water-controlled or seat-operated flush valves and from bathtubs, washbasins, laundry tubs, or other fixtures in which the spout (discharge end of the water line) is lower than the fixture rim, or worse, below the fixture overflow. Vacuum and siphon action may be destroyed by opening the highest connected faucet or an air cock in the top of the water line or by equipping the system with suitable automatic vacuum breakers.

All waste pipes and traps are subject to fouling. Dirt collects in the bottom and grease adheres to the sides. The usual way of clearing ordinary fixtures traps is to unscrew the clean-out ping, as shown in figure 9, and wash out the obstructing matter or pull it out with a wire bent to form a hook. Small obstructions are often forced down or drawn up by the use of a simple rubber force cup (sometimes called "the plumber's friend") costing 30 to 60 cents. This device is shown in figure 10. The cup is placed over the fixture outlet and the fixture is partially filled with water. The wood handle of the cup is then worked rapidly down and up, causing alternate expulsion of the water from beneath the cup and suction upward through the waste pipe and trap. If a trap and the waste pipe from it are clogged with grease, hair, or lint, it is best to open or disconnect the trap and dig out the greasy matter with a stick. The use of chemical solvents in waste pipes is explained in Farmers' Bulletin 1426, "Farm Plumbing."

A variety of inexpensive flexible coil wire augers and sewer rods are available for removing obstructions—mainly newspapers, rags, toilet articles, grease, garbage, or other solids—from traps, waste pipes, sewers, and drains. The growth of roots in sewers and drains causes much trouble which better workmanship in making the joints would have avoided. Augers and rods come in various sizes and lengths. Stock lengths for clean-out augers for closet bowls are 3, 6, and 9 feet and cost from $1 upward. Figure 11 shows two kinds of flexible augers for general purposes. The upper is 4 feet long and has a small steel cable from the handle to the wire hooks. The hooks can be drawn into the coil, thus facilitating entry into a trap. The lower auger is 8 feet long, has a crank handle and corkscrew point generally preferred for closet-bowl work. Placing a few sheets of toilet paper in the bowl and then flushing usually indicates whether the obstruction has been dislodged.

Flexible coil steel waste-pipe cleaners commonly come in diameters of ³/₁₆, ¹/₄, ³/₈, ¹/₂, and ⁵/₈ inch and in lengths of 6, 9, 15, 25, 50, and 100 feet. The ³/₁₆-inch size in 9-foot length without handle or corkscrew point costs about $1. The ¹/₄-inch size in 9-foot length with automatic grip handle costs slightly more. The small sizes are very useful in sink, lavatory, and bathtub traps and waste pipes.

Flat steel sewer rods, equipped with either an oval or a revolving spear point and an automatic grip handle, come in stock lengths of 25, 50, 75, and 100 feet, in widths of ¹/₄ to 1¹/₂ inches, and in thicknesses of ¹/₁₆ and ¹/₈ inch. A rod ¹/₁₆ by ³/₄ inch and 50 feet long costs $4 to $5; a rod ¹/₈-inch thick, costing $5 to $8, is desirable for ordinary sewer-cleaning purposes. Round sewer rods of ⁷/₈-inch hickory or ash in 3- or 4-foot lengths with hook couplings and simple sewer brushes and root cutters are described in Farmers' Bulletin 1227, Sewage and Sewerage of Farm Homes.