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Conservation of market buildings
Many existing enclosed markets have evolved almost accidentally. Decisions made to alter premises in the past may no longer be relevant or may simply reflect policies which are no longer followed. Political expediency may have forced market operators to implement changes which are counter-productive to the smooth functioning of a market. For example, problems may be the result of the re-allocation of stall space for fresh produce to vendors of other products (e.g. clothing), who are willing to pay slightly higher rents or other inducements. Strict enforcement of market regulations, poor revenue collection and the lack of periodic maintenance are also frequent problems.
Before deciding how to improve an existing covered market the physical fabric and operating procedures used in the market should be examined objectively. It does not automatically follow that a market was well designed when it was originally constructed. For example. entrances and service access may have always been inadequate, exacerbated by recent growth in traffic levels. Some markets are located in basement premises and others have irregular internal layouts. with obstructions in customer flow caused by narrow aisles or because of the placing of structural columns.
The market upgrading programme may necessitate, for example, the building of new lock-up premises for non-food product traders, in order that they can be re-located outside the market hall. The overall layout and approach to a covered market may have to be altered so that wider door openings are provided, natural lighting and ventilation improved by enlarging window openings and service access provided at the rear of the premises. Stalls may have to be re-positioned and aisle widths increased so that there is more room for customers to move around safely and for produce to be visibly and more hygienically displayed. A typical proposal for market upgrading is illustrated in Figure 62.
For fish and meat markets, existing stalls are often in a poor sanitary condition. Wall and floor finishes may have to be renewed so that they can be properly cleaned and running water and power may have to be provided. Figure 63 illustrates a simple stall for the sale of fish and meat, appropriate for a new or upgraded covered market. Particular features to be noted in this illustration are the easily-cleaned, light-coloured ceramic tiled walls and non-skid flooring, the individual water supply to each sales unit and the display areas using easily cleaned materials, such as terrazzo, marble or stainless steel. Concrete is also used for stalls. This may be appropriate for fruits, vegetables, spices and grains, but is not really suitable for meat and fish. There is often a tendency for the butcher or fishmonger to consider the concrete surface suitable for chopping, but it cannot be really kept clean and maximum encouragement should be given to using a separate cutting board or block. A detail not shown in the illustration, but frequently used, is a pull-down wooden or steel shutter to provide night security.
This section broadly reviews some of the typical market infrastructure design problems and the solutions that are used in terms of materials, construction methods and standards. Typical dimensions for the layout of stalls for roadside and open markets are shown in Figure 64. Similar dimensions to those used in an open market square would be applicable to the inside layout of an enclosed market. Overall infrastructure standards are summarised in Box 10. Further details of engineering design criteria are given in Chapter 14 of the Wholesale Markets: Planning and Design Guide (FAO, 1991).
BOX 10
Typical market infrastructure standards
Roads and parking areas
All markets, however primitive in their level of facilities, require some form of vehicular access. Farmers and traders need to bring and unload produce. Consumers need to reach markets by bus and other forms of public transport and, in some cases may use private cars to do their shopping. With a simple market the best form of access is a stopping point for public transport at the front of the site and service access from the sides and rear of the premises. A more complex market, particularly a rural assembly market or an urban market which has a partial wholesaling function, will have its own internal road system. However, retail markets in general should be the domain of the pedestrian, at least during their main hours of operation.
Parking provision will be dependent on the level of car ownership within society, the standard of public transport and the catchment area of the market, i.e. whether it serves an area wider than immediate walking distance. In some cases, the provision of parking areas for bicycles and motorcycles can be more important than that for cars.
Sidewalks
At low levels of car or vehicle usage, such as with rural retail markets, no special provision needs to be made for pedestrians. For urban markets, however, traffic conditions are likely to make some form of pedestrian segregation essential. The whole market area itself may be designated as traffic-free, except for periods when delivery vehicles are allowed to enter.
With street markets and where there are very high traffic densities, such as in the centre of major cities, the segregation is often more effectively achieved by widening the sidewalk (an absolute minimum of 4 metres) parallel to main roads. The edge nearest the road (i.e. the kerb-side) would contain the more intensive activities such as hawkers and street stalls. The preferred clear width of the sidewalk should be 5.2 metres, which allows 2.5 metres for general circulation on the sidewalk, 1.2 metres in front of the stalls for customers and 1.5 metres for the stall itself (assuming that the seller does not stand behind the stall - in which case a further 1.2 metres is needed). A variant of an area of stalls and vendors running parallel to the main street is the "Rambles" in Barcelona - where the main pedestrian route is down the central reservation of a street. A similar Italian example is shown in Figure 48, where the market structure has been inserted into the centre of a street.
Where paths and roads cross it is conventional practice to provide some form of crossing where the pedestrians can have priority. The zebra or pelican crossings, where pedestrians have right-of-way over vehicles, are typical examples. A more effective method at markets might be to provide a physical interruption in the road so that vehicles are forced to slow down. The surface itself might be altered, a speed-hump ("sleeping policeman") provided or, most effectively, the road width section might be reduced for through-traffic and the pedestrian pavement surface might continue at its normal level across the road (say 150 to 300 mm above the road surface), with the road ramped-up on either side (with a maximum slope on the ramps of 17 per cent).
Arcades and street coverings
To provide comfortable conditions for walking and shopping the sidewalk is often covered by an arcade, sometimes with the edge protected by a low wall, fence or seating. Such arcades or covered walkways are a common characteristic of traditional shopping areas in many parts of the world, defining the edge of spaces and providing shade for pedestrians from rain and heat. To persuade private shopkeepers to construct an arcade it may be necessary to make the construction a condition of giving planning permission or a building permit. A variant on arcades is the semi-covered street which uses trellises, mats, nets or vines to cover the full width of a narrow street in order to filter sunlight and provide shade. These structures can be used to span between shops lining the market street or in conjunction with arcades.
Pitch markings
For street markets the area allocated to the traders, usually termed a "pitch", should be clearly delineated. A typical example from a street market improvement programme in London is shown in Figure 65. There are a number of methods for defining pitches including: conventional roadline painting techniques; using a different material (e.g. defining the pitch using a concrete strip or a different colour of brick or stone); or using white thermoplastic paint baked onto bricks. The most important consideration is that the paint or other method of defining the pitch should not be worn-off with normal foot traffic.
The sizes of the pitches should be based on the experience of stallholders' needs. It will also be important to distinguish each pitch by numbering. Again, a technique of painting the pitch number on the paving is the simplest method. Pitches can also be numbered by using pre-numbered, pre-cast concrete or bronze plates set into the street surface or by numbering a post or bollard adjacent to each pitch.
Paving and surface water drainage
Except in the simplest of rural situations, a market area is likely to have completely paved surfaces, using asphalt, in-situ concrete or, where vehicle traffic is minimal, some form of paving units such as pre-cast concrete or stone flags. The cost of paving can often use up most of the limited budget that is available for market construction and maintenance. Finding an economic solution to paving is, therefore, an important issue. Although easy to clean and wash down, the continuous paved surfaces of markets can cause severe run-off and erosion problems. For these reasons small-scale, rural markets may be effectively paved using more traditional paving materials, such as low-fired brick paving stones or stone cobbles or even crushed and rolled gravel, which allow some of the rainwater to be absorbed into the sub-soil.
FIGURE 66.Typical drainage channels and kerbs.
Source: Cartwright R. M (1980). The design of urban space.
The Architectural Press Ltd., London, England.
A key factor in designing any paving system will be the method of drainage. Clogging of poorly designed or maintained drains is a common feature of many markets. With a small market there may be no necessity to have any internal drains within the market area - all the rainwater can run to perimeter drains. This will not be possible in larger markets where internal drains will need to be installed. This presents two problems: the difficulty of routine cleaning, particularly of debris from vegetables, and the potential obstruction the drains introduce, both to delivery vehicles and foot traffic.
To counteract this, as shown in Figure 66 for example, the drainage channels are set as flush as possible with the general level of the paving. Trapezoidal or dished-shaped drains are generally easier to keep clean and are less damaged when a vehicle inadvertently enters them. Drain covers using fixed steel grills are invariably damaged and should be avoided and if covers must be provided they should be of a lift-out type. Ignoring these problems will not help, as market users often take matters into their own hands by, for example, back-filling a drain with earth so that it does not cause an obstruction to handcarts. Like any drainage system the alignment and gradients should be designed to obtain a self cleansing velocity and to achieve this it is better to start the drainage runs with a minimum invert at grade (i.e. the drain bottom at the same level as the pavement).
A major criteria for improving paving of a market should, therefore, be that the paving and associated drains should not present any tripping hazard to market users. With the upgrading of existing market areas, this may necessitate the raising of road levels to match that of the surrounding paving and sidewalks, together with the removal of herbs. If materials such as stone or granite sets are used for paving they should have as large a face area as possible so that there is a minimum disruption to disabled people and those wearing high heeled footwear.
Electrical supply and street lighting
For permanent markets an electricity supply will often be essential, both for security reasons and so that trading can be extended beyond the hours of daylight. This is unlikely to be affordable in most rural markets, except those located in more important rural towns. For urban street markets a general lighting system will need to be provided, either using conventional street lights mounted on lamp standards or fittings attached to adjacent buildings (the spacing for these fittings will usually be in the range of 15 to 20 metres).
In some cases, an individual electrical supply may be appropriate. The normal, unofficial method for delivering a supply to traders' stalls is by using an overhead (catenary) cable either coming from a friendly shopkeeper or from socket outlets mounted on adjacent walls. This is potentially dangerous and will probably not conform with local electrical supply regulations. One way of getting around this problem is by using a special electrical fitting mounted onto a pole or incorporated into a bollard. The latter involves fitting a lockable door into a hollow-section, cast-iron or steel bollard, into which an electrical socket outlet is installed. The cable leading to the outlet normally comes via an underground duct, connected to a remote meter - which can record electrical consumption on the basis of part of the market or for the individual stallholder.
Lighting for covered markets is relatively easy as light fittings can be suspended from the roof structure. The important point to remember is that the fittings should be robust (either industrial quality pendant fittings or fluorescent tubes) and easily accessible for replacement of bulbs or tubes. Long-life, low-energy fittings are highly appropriate for market buildings. Maintenance procedures for replacement of fittings should not be fully relied upon and all areas of markets should also have some form of natural light from windows or roof-lights. In addition to lighting, traders, particularly those operating stalls selling meat, fish or dairy products, may need an electrical power supply for running a small refrigerator or chiller cabinet. Separate metering to maintain energy conservation is essential in this case, unless a special charge is built into the stall rent.
An auxiliary power supply may be necessary, particularly in rural areas where no mains supply is available. This is usually obtained using diesel-driven generator units. The environmental impact of such a provision needs particular attention, i.e. air pollution from poor equipment maintenance and diesel spillages from the generator itself or from on-site fuel storage tanks. A well-constructed concrete apron, with an upstand, should be provided to minimise potential risks.
Water supply, sewerage and other infrastructure
A water supply at a reasonable walking distance is an important element in markets, particularly for washing-down the market area. For urban markets a piped mains supply is usual, but with rural markets a pumped supply from a bore-hole is often required. This will usually mean that the pump will require a concrete apron to protect the supply from being contaminated and that it will probably need to be located on the perimeter of the market. However, the overflow from the pump can be used to flush-out drains and should not be directed straight to an outfall.
For both covered and open urban markets water is normally provided on a group basis from stand-pipes. Bollards can also be modified to incorporate a tap. For butchers and fishmongers the water supply should ideally be on an individual basis, but to reduce costs one water point can be provided for every four users.
FIGURE 67.Detail of steel gate/barrier, Berwick Street, Soho, London
Source: Westminster City Council
Standards for providing toilet facilities (latrines and urinals) are shown in Box 7 in Chapter 3. It is important that no toilet provision is made without there being an integral or nearby water supply for washing hands and, where no mains sewer connection is available, without provision being made for some form of on-site treatment of effluent (e.g. a septic tank).
Garbage facilities and cleaning services are discussed in Chapters 6 and 7. It is important to remember, however, that there is little point in providing containers (skips) or constructing garbage pits if a collection system has not been set up as part of the routine maintenance programme. The provision of small, easily cleaned garbage pits? or preferably dustbins or paladins spread throughout the market area is preferable to the provision of large pits remote from the users.
From the point of view of infrastructure provision it is important to ensure that these facilities are located so as to minimize their potential contamination of ground water sources.
Site landscaping and outdoor seating
A small part of the development budget should be set aside to provide facilities that will make the market more comfortable for the users. Advantage should be taken of existing shade trees and new trees planted wherever possible. The trees should be protected 'from damage by tree guards, typically a low wall or a cast-iron grating surrounding the tree. Other forms of site landscaping should only be introduced if it is possible to maintain them.
For larger markets outdoor seating is often provided. This needs to be located to take account of both views and climate, which means that seats should face into the activities of the market and be climatically appropriate, i.e. shaded in hot climates, protected from wind, or face into the sun in cooler climates. Low walls (a minimum 400 mm in height and 300 to 500 mm deep) are an economic means of providing seating.
Enclosure of sites for security purposes is a common feature of many open and covered markets. This can be provided from the walls of buildings around the perimeter, close timber fencing, brick or block walling or using chain-link fencing. Gates can be made from timber, steel or framed chain-linking. Gates are usually left open during working
hours of the market, although if limited vehicle access is allowed during this period (or there is a requirement for charging an entrance fee based on the vehicle type) the use of a hinged barrier is appropriate. For urban street markets the need may be to keep traffic out during the period of market operations and Figure 67 illustrates a welded steel hinged barrier used for this purpose in London street markets.
