Drainage Of Roads

It teems to be generally conceded by authorities on road making that either macjulam or telford roads are best for country and suburban traffic. Each style has ita advocates, butthe difference between thcm is not so great as to be of material importance. Telford pavements consist of a metaling laid on a foundation of comparatively large stones set on edge; in macadam roads the foundation is omitted and the layer of broken stone is laid directly on the soil. That each method has merit no one donies, and it is practically conceded that either one fully filis he requirements of a good road. The spread of the agitation for highway improvement in the United States during the past two or three years has been enormous. The country has apparently reached that stage of development which calis, not for temporary makeshift3, but for permanent construction in roads as in other {tinga. The farmers have ceased to be satisfied with ha ving their f arias connected to the markets by poorly built and seldom repaired highways which increase byone-half the draft in transporting produce. They demand smooth and substantial thoroughfares, and their demands are all that is necessary, for with themselves rests the Bolution of the problem. In the building of good roads there are one or two matters which cannot be looked after too carefully, and which should be thoroughly understood by every one who pays taxes, that they may be carried out. Every person who is benefited by the construction of good roads should be sufficiently interested in the subject to inform himself of the essentials of their construction, as a ineasure of self defense if nothing else. After the style of road to be built has been decided upon the most important consideration is that of drainage. "Whether a paved bottom be laid or not," says Codrington's treatise, "it is a matter of the first importance that the seat of the road should be thoroughly drained. " It is probable that more money has been wasted through the disregard of this fact than would be necessary to send a copy of the book which emphasizes it to the council of every town and city of the United States. Road makers seem to be about equallv divided between flat and concave bostoms. Macadam's idea was that the metaling or covering of broken ston should be water tight, and if this is successfully accomplished a flat bottom would seem to have no particular disadyantages. If , however, the metaling ba so laid as to admit the filtration of water from the road surface to the bottom a flat bottom would be vastly inferior, for it would offer no slope to cause the water to make its way to the sides and thence into the ditches, but would force the water to pool and sof ten the bottom in places to a greater or less extent, with the inevitable result of damage to the thoroughfare. As in order to make the metaling absolutely water tight ceaseless care is necessary, and as the construction of concave bottoms is almost as simple as that of a flat bottom the former is probably the better plan of the two. It ia genorally safe to rely on side ditches or dralns to keep a well built road free from water. They should be of good depth, say three feet below the road surface, and free comniunication between them and adjacent natural water courses should always be maintained. Where side ditches do not prove sufficient to carry off the moisture cross drains should be prepared at frequent intervals in the surface of the road. These run at an acute angle from the side ditches and meet in the shape of a V in the center of the road and run in the direction in which the road f alls. It is generally sufflcient to make these by digging six inch ditches, which are filled in with loose stone or rubble, but box drains with dry stone walls and a flat bottom and cover stone have, raggests Codrington, the advantage that they can be easily opened from above and cleared if they get stopped. Another matter connected with drainage ia worthy of careful attention. This ia the provisión for allowing ditch water and streams to pass from one side of the road to the other. For this purpose cross drains and culverts are necessary. To quote Codrington again: "These must be constructed where required and to suit the particular circuinstances of the case. There is an advantage in ha ving culverts under a road sufficiently large for a man to pass through for examination and repairs; smaller ones may be either barrel culverts, earthenware pipes or box drains. It ia not advisable to give much inclination to culverts and drains- suf - flcient to clear them of water is enough. The scour caused by the too rapid flow of the water te destructivo, and a drain with a Bteep inclination is more liable to obstrnction than one with a moderate f all." Of the surface drainage of roads Codrington saya: "It ia essen tial for the proper and economical maintenance of a road that the rain should flow freely off the surf ace. Water standing in ruts or holló ws is injurióos in two ways - it greatly increases the wear of the trafile, by which the hollow in which it lies is conthmally deepened and enlarged, and it soaks in and weakens the whole crust of the road and the subaoil beneath. Such a cross section should theref ore be given and carefully maintained as will throw the rain water off freely, and a very moderate inclination from. the center to the sides of the road ia found to be best for thia purpose. On a road too convex or high in the center there is a tendency for the traffic to f ollow in the same track along the middle of the road, being the only part where the vehicles can run upright, and hollow tracks are worn by the wheels and the horses' feet which retain the water, so that the road Is not so dry and wears more unevenly than one of a flatter seoüon on which tha traffic is more evenly distributed ovef gieentire width.