To Build a Sewer on Piles.
The building of the new sewer which is to occupy the Aramingo canal from the river to Huntingdon street, Philadelphia, and over which the proposed Aramingo avenue is to be located, presented great difficulties to the engineers. At first it was intended to build piers and lay the sewers on a system of connected arches, but this was abandoned as too costly. Another plan was decided upon, and the work of preparation is now being rapidly pushed. The difficulty en. countered was the toft mud at the bottom of the canal, and this ia now to be overcome by a moat cxtenaive system of piling.
Great yellow pine timbers, twelve inches square, are to be driven to solid bottom, three feet apart. Transversely in these will rest yellow pine planks, eight by eight inches. Broken stone will be filled in two feet deep around the heads of the piles to brace them. On the transverse timbers is a plank flooring, six inches thick, and above this the sewer is built, secured at the bottom by a bed of heavy stones laid in concrete. The main sewer will be nine feet six inches in diameter. Below York street there will be twin sewers, each eight feet in diameter.
The construction of the canal sewer necessitates the entire reconstruction of the ten-foot sewer on Huntingdon street as far westward as Sepviva street, in order to secure the proper slope for drainage. The work will cost nearly $1,500,000, and will be completed under favorable conditions in about a year.