THE DRAINAGE OF THE CITY AND SUBURBS.

Globe, Volume VIII, Issue 850, 15 March 1877, Page 2

THE DRAINAGE OF THE CITY AND SUBURBS.

Mr William White has addressed the following letter on this subject to the editor of the Press:

Sib, —As the people in and about Christchurch seem to be getting very anxious about the drainage of this city and its suburbs, and as it is known that I have given the drainage of Christchurch some consideration, it may not be taken amiss if I make known my views on this subject. I will not burden this letter with any detail, but try to explain the leading features of my plan in as short and simple a way as I can. I must at once state that I don’t think that there is any known plan better adapted for the removal of night soil from this city than the plan known as the pan system ; although this plan can be carried out in a much cleaner way, as pointed out by Mr Jamieson others,

Now, as regards the carrying away of of house slops and keeping the district clean, I consider we must have an abundance of water distributed about, and running through the district, to carry away and thoroughly dilute the house slops as they leave the house?, I propose that the house slops should be allowed to run bom the houses into the side channels, and the side channels be supplied with as much water as will thoroughly dilute and carry them into an open drain that should run through the lowest part of the district and into the deep stream that runs through the estuary at low water level. I would construct this open sewer of concrete sides and bottom, capable of being swept down from a small punt floating in the sewer, as often as required. I would also attached to the outlet of all the side channels, when* they empty into the sewer, a sieve of not more than half inch mesh ; these sieves to be attended to by the scavengers. And in addition to the house slops being diluted in the side channel?, 1 would let into the open sewer from the river at different places an abundance of water, so that when it is emptied into the deep stream in the estuary, no possible harm could result from it.

And now as to the supply of water to run down the side channels, I propose to fetch that from the head of the Avon, as it is the nearest place where we can get a height of water that will run through Christchurch and its suburbs. And if afterwards the district should require a great head or pressure of water, the pipes laid to the head of the Avon would be in a good line for the river Waimakariri. I believe that a little reflection will decide that this plan is as simple, cheap, and effectual as has been put forward as yet, I think that all the Drainage Board should do is, supply sufficient water to properly flush out all the side channels, and a proper drain to convey the water away again into the deep water stream in the estuary. And if it is part of the arrangement that the cost of making the side channels shall be borne by the Drainage Board, it would be, I think, well to let the Road Boards do them, and the cost be refunded by the Drainage Board. If the City Council or the Road Boards formed the mads, and the Drainage Board made side channels, the work would not be done so cheaply, and their levels might clash. So it will be seen that all I propose that the Drainage Board should be called on to do, is, first, to supply a sufficient quantity of water to flush out the side channels, and secondly, to provide a sufficient drain to cany the water away again, I will again state that I have purposely left out all mention of detail, thinking that the system will be better understood without being so encumbered. If the Drainage Board wilLadopt Sthis plan, I shall be hrppy to give all details for the successful carrying out of this system ; but if the engineer to the Drainage Board is instructed to adopt this plan, I am sure he will want no assistance. As will be seen by a little reflection, the whole thing is perfectly simple and easy. Before concluding, I may state that in times of heavy rains, I would stop the supply of water from the head of the Avon, and leaved the side channels and outlet drain free to carry off storm water. I wish it to be clearly understood that I would apply fo the suburbs the same treatment as s proposed for the city. I am, Sec, William White.