In preparing his plan, Mr. Forster had the advice and assistance of Mr. Haywood, of the City Court of Sewers.
The metropolis is divided into two portions—“the northern portion of the metropolis,” or rather that portion of the metropolis which is on the north or Middlesex bank of the Thames; and the southern portion, or that which is on the south or Surrey side of the river.
The northern portion is in the new plan considered to “divide itself into two separate areas,” and to these two areas different modes of sewerage are to be applied:
“1. The interception of the drainage of that district, which, from its elevation above the level of the outlet, is capable of having its sewage and rainfall carried off by gravitation.
“2. The interception of the drainage of that district, which, from its low lying position, will require its sewage, and in most localities its rainfall, to be lifted by steam-power to a proper level for discharge.”
The first district runs from Holsden-green (beyond the better-known Kensall-green) in the west, to the Tower Hamlets in the east. Its form is irregular, but not very much so, merely narrowing from Westbourn-green to its western extremity, the country then becoming rural or woodland. Its highest reaches to the north are to Highgate and Stamford-hill. The nearest approach to the south is to a portion of the Strand, between Charing-cross and Drury-lane. Care has evidently been taken to skirt this district, so to speak, by the canals and the railroads. This division of the northern portion is described as “the district for natural drainage.”
The area of this division is about 25⅙ square miles.
The second division meets the first at the highway separating Kensington-gardens from Bayswater; and runs on, bordering the river, all the way to the West India Dock. Its shape is irregular, but, abating the roundness, presents somewhat of that sort of figure seen in the instrument known as a dumb-bell, the narrowest or hand-part being that between Charing-cross and Drury-lane, skirting the river as its southern bound. At its eastern end this second district widens abruptly, taking in Victoria-park, Stratford, and Bromley.
The area of this division of the northern portion is 16⅛ square miles.
There are, moreover, two small tracts, comprising the southern part of the Isle of Dogs, and a narrow slip on the west side of the river Lea, which are intended to allow the rainfall to run into the Thames and the Lea respectively.