SEPT. 6.] THE NEW ZEALAND GAZETTE. 2347

Laying of drains.

(5.) In respect to the laying of drainpipes the following provisions shall apply :--

(a.) Earthenware pipes shall be laid uniformly in straight lines and true to the specified gradient, and the bottom of the trench shall be grooved to receive the collars of the pipes so that every pipe shall rest evenly on solid ground throughout the whole length of its barrel.

Making of joints in drains.

(b.) The spigot of each earthenware pipe shall be fitted evenly and concentrically into the socket of the next adjacent pipe, and pushed in as far as it can go ; and the space between such spigot and such socket shall be filled evenly with cement mortar or other approved composition, and the interior of each joint shall be cleaned so as to have an even surface before the next pipe is laid.

Drains in wet ground.

(c.) Wherever any drain passes through wet or soft ground, or in any other case where so ordered by the Engineer, all earthenware pipes shall be laid on a bed of concrete not less than 3 in. in depth, and such concrete shall be grooved to receive the collars of the pipes so that every pipe shall rest evenly throughout the length of its barrel on such concrete bed ; and after the joints between the drainpipes are made concrete shall be filled in evenly in the space between the pipe and the wall of the trench to a height not less than half the diameter of the pipes :

Provided that wherever there is danger of tree-roots penetrating the joints of the pipes, or wherever in the opinion of the Engineer the conditions so warrant, the drainpipes shall be wholly surrounded by a covering of concrete of a thickness of not less than 3 in. :

Provided further that cast-iron pipes may be substituted for earthenware pipes, and in such case the cast-iron pipes shall be laid so as to rest evenly on a firm bed of concrete, broken stone, or other approved foundation.

Cast-iron drainpipes.

(d.) Cast-iron drainpipes shall be laid in straight lines and true to the specified gradient, they shall be so supported as to prevent alteration in line or grade, the spigot of each pipe shall be pushed as far as they will go into the socket of the next pipe, and the joint shall be made gastight in the manner provided hereinafter in clause 20.

Conditions when drain passes below a building.

(6.) Except with the sanction of the Engineer, no person shall construct any drain so as to pass under any building or portion of a building, and wherever the Engineer has given such sanction the drain shall be constructed subject always to the following conditions, that is to say :--

(a.) The drain shall be laid in a straight line for the whole distance that it passes under the building.

(b.) Wherever the drain passes through a wall, the opening in such wall shall be of such size as to leave a distance of not less than 3 in. between any part of the drain and the nearest part of the wall.

(c.) Where earthenware pipes are used in the construction of the drain they shall be laid on a foundation of concrete of not less than 4 in. in depth, and shall be surrounded by concrete filling so that at the sides of and above each pipe there shall be a covering of concrete not less than 4 in. in depth.

(d.) Where cast-iron pipes are used they shall be supported to the satisfaction of the Engineer, who may further forbid the use of any pipe which has not passed an approved test.

Covering and protection of drains.

(7.) Subject to the provisions of the last preceding subclause, every drain shall be covered with earth carefully rammed and consolidated to a depth of not less than 12 in. from the level of the surface of the ground to the upper surface of the drain ; and in the case that such covering cannot be provided, then the drain shall be covered with concrete or other material as may be directed by the Engineer :