COSTS
have
Estimates were made in 1958 of the current capital and operating costs of the various systems. While these cost figures may now increased, comparison is still valid.*
Capital costs
The capital costs of communal container and chute systems of various kinds were estimated for a number of examples based on actual schemes. Those for the Garchey system were deduced from published data, bills of quantities and in- formation supplied by the patentees of the system. Descriptions of the various systems examined and their estimated capital costs are given in Table 1. The numbers of dwellings have been adjusted where necessary to relate the figures to the disposal capacities recommended above (3 ft3 per dwelling per week for communal containers and 3-5 ft for chutes). The first figures for chutes in the third and fourth columns relate to the estimated 3 ft3 capacity and the second to the 5 ft3 capacity.
fore the cost, of collection the capital cost per dwelling of a given system may be reduced.
To allow a comparison of the various systems, therefore, both capital and running costs must be taken into account. This has been done on the basis of a very broad classification and the result is
set
out in Table 2. For this purpose. typical capital costs have been taken, both for the more or less permanent parts of the installations, such as hins, containers and hoppers, which may require frequent replacement. The costs of all these are expressed on an annual basis, as are also main- tenance and service charges and the costs of collection and disposal. The figure for these last two items for the Garchey system is a nominal one to cover the disposal of waste not suitable for the system and of clinker from the destructor unit.
DISPOSAL SYSTEMS
Dustbins
The dustbins serving blocks of flats are generally positioned at
Table 2
ESTIMATED OVERALL COSTS PER DWELLING
Item
System
Dustbins
Communal containers
Chutes
Garchey system
Annual cost of permanent part
71-
25/-
Annual cost for replaceable part
8/-
10/-
9/-
100/-
Unknown
Maintenance and service charge
6/-
6/-
65/-
Collection cost
30/-
20/-
20/-
5/-
Disposal cost
10/-
10/-
10/-
Total annual cost
48/-
53/-
70/-
170/-
Overall costs
Capital and running costs of refuse disposal systems to some ex- tent counterbalance since by in- creasing the frequency, and there-
* In this connection attention atten- tion is also directed to Appendix 5 of 'Homes for Today and Tomorrow' Published in 1961 by H.M.S.O. for the Ministry of Housing and Local Govern- ment. Cost figures then available from the Birmingham City Council showed a rather higher extra cost for the water- borne system compared with chutes than is indicated here.
134
ground level, though they may be placed on upper floors, either in groups or singly outside individual flats. At ground level they may stand in the open or be enclosed or housed in a variety of ways, and they may be in large or small groups according to the design of the block and the form of access.
The user study has shown that tenants accept dustbins at ground level even if it necessitates a journey down by stair from the second or third floor, or by lift from
a much greater height to deposit re- fuse. They dislike walking some distance in the open at ground level, especially if the route is in full view of passers-by. Thirty feet seems to be about the greatest acceptable distance.
Enclosure or housing of dustbins, though desirable from the points of view of appearance and protection to the user, requires to be arranged with care. If it is intended that each household should have and retain exclusive use of a particular dustbin, it is necessary to ensure direct and easy access to all bins, as otherwise only those most easily accessible will be used. Thorough cross-ven- tilation of roofed dustbin enclosures is most essential to prevent cumulation of smells.
ac-
In the user study 83% of tenants expressed general satisfaction with dustbin disposal, though 60% re- ported smell from the bins. Forty- six per cent had suggestions to make for improvements, mostly with the object of eliminating smell or im- proving the convenience of the dustbin enclosure.
Communal containers
The containers used in communal container
are systems
normally cylindrical in shape, 3 ft in diame- ter, 4 ft 3 in. high and of 14 yd3 nominal capacity (see B.S. 1136, *Mild steel refuse storage con- tainers'). They are designed to be lifted and emptied dustlessly by a special collecting vehicle. They are in a position where they may be of necessity placed at ground level, easily wheeled, either by lifting trolley or on their own wheels if provided, to the collecting vehicle. They may stand in the open or be enclosed or housed in a variety of ways. Where a container is not ful- ly enclosed, or is in an enclosure which the user enters, it is generally provided with a lid which has a small opening part for the insertion of refuse. In all cases, because of the height of the container, it is necessary to provide a raised plat- form for access. It should be 2 ft 9 in. to 3 ft. 6 in. below the opening through which the refuse is to be placed, and usually requires four or five steps up from ground level. For the elderly or infirm, care should be taken with the placing and
THE HONG KONG & FAR EAST BUILDER
VOLUME 18. NUMBER 5
Page 140Page 141
BUILD YOUR OWN
storage racks
cheaply, quickly
and efficiently,
to any layout or design,