3. Physical and Technical Characteristics
3.1 Physical Infrastructure

3.1.1 Capacity of Systems

The Water and Sewerage Authority (WASA) operates nine urban water systems, and, in addition, provides water to 19 villages, mainly through the extension of its urban systems. Consequently, WASA provides potable water to approximately 119,222 people which represents 56% of the total population (see Table 13). Annex 2 presents a detailed list of communities and their facilities by district.

Table 13
Population Served by Type of System

Source: Estimates based on information from WASA and RWSSP.

An analysis of Table 14 shows that due to the flat terrain, all systems include pumping stations which increase the operation and maintenance cost of the systems, and, therefore, initial capital costs are high.

Since most urban systems were constructed in the 1970s they are reaching or passing their design life of 20 years. To satisfy the demand of the growing population, these systems will have to be upgraded and the distribution network will have to be replaced in order to reduce losses and maintain sufficient pressure in the system.

Rural Water Systems

In Belize, the rural water systems are called rudimentary water systems and are generally located in villages with a population greater that 250. They usually consist of a well with an electric submersible pump, discharging to an elevated tank, and a piped distribution network. Very few of these systems receive disinfection. Technical assistance for the design and construction of these systems is provided by WASA. Upon completion, the system is operated and managed by a local board of management. Connections are made from the distribution mains up to approximately 1 m inside the yard, and thereafter piping is the responsibility of the property owner. There are currently 65 villages in the country served by rudimentary water systems, covering 40,296 people, representing 35% of the total rural population and 19% of the total population in the country.

Table 14
Description of the Urban Water Systems

Source: Water as a Natural Resources by WASA, April 1992.

3.1.2 Quantity and Sources of Supply for the Urban Systems

The main usage of water resources in Belize are: Industry, public water supply, private water supply, agriculture, and hydropower generation. There are no statistical data related to the nonpublic supplies to determine relative proportions, but the above order is thought to be the order of magnitude. No details are available of the number of private water systems nor of the quantity of water abstracted by such systems. The systems can range from shallow wells for personal use to deep wells or bore holes from which supplies are obtained for commercial, agricultural, or industrial use. Large concerns such as the Belikin Brewery at Ladyville have their own private wells and treatment plants.

The number of customers of the urban system is 29,505, which is an average water production per person of 50 GPD. Based on data of five villages, the amount of water extracted for rudimentary water systems is approximately 40 GPD. It should be noted that the average water production per person for Belize City is approximately 70 GPD and for the smaller urban towns it is approximately 40 - 45 GPD, about the same as for the rudimentary water systems (see Table 15).

Table 15
Urban Sources and Production Rates

Unaccounted-for-water at WASA was officially recorded as 45% in 1991. Current figures show an increase to 57%. For the purposes of this analysis, it is necessary to point out that unaccounted-for-water is defined "as the difference between the recorded production and consumption (billed) of water". A significant factor attributable to the amount of unaccounted-for-water is the fact that there are a large number of domestic water meters that measure quantities in Imperial Gallons (instead of US gallons). This factor accounts for approximately 10% "under-registering" of the water consumed, as shown below:

(i) Meter Error (15%) = delivery points (3%) + consumers (2%) + unit of measurement (10%)

(ii) Authorized Unmetered Usage (5%) = street cleaning (2%) + fire fighting (3%)

(iii) Illegal Connections (3%) = at distribution main (3%)

(iv) Leakage (22%) = major lines (5%) + small diameter mains (7%) + house connections (10%)

Hand Pumps

There are approximately 790 bore holes equipped with hand pumps of which 715⁸ are functional, located in small and/or dispersed villages with a population of normally under 250 people. They are installed by and subsequently maintained under the Rural Water Supply and Sanitation Programme. During 1994, a survey of all hand pumps was carried out and data were tabulated in a geographic information system.

Bore holes for hand pumps are drilled to depths of between 30 ft. (9 m) and 120 ft. (36 m). Normally 4"diam. P.V.C. casing is inserted to the full depth and a gravel pack sealed with bentonite cement is provided over the top 20 ft. Disinfection is not provided on a continuous basis but periodic shock chlorination treatment is provided when contamination is reported by the Public Health Bureau. The Public Health Bureau is responsible for monitoring water quality every year. The type of pump now being used is the India Mark II which is capable of withstanding a certain amount of misuse and can perform in depths of up to 45 - 50 m. Most recently the "Maya" hand pump has been introduced for shallow wells of up to 14 m. One hand pump is intended to serve 10 families but usually about seven families are served.

3.1.3 Design Procedures

There are no written design standards approved by WASA to guide the design process of water and sewer systems. But, from dialogue with WASA technical staff it can be concluded that the current design approach reflects reasonable norms and standards. However, several areas could use modification which could reduce costs. These include the water consumption level for which systems are designed and tank dimensions. Storage tanks are sized to provide one full day's demand, which exceeds the common norm of 0.3 - 0.4 day's demand. When combined, these two factors lead to large storage volumes. Especially in flat terrain where storage tanks must be elevated, storage costs can be a major part of rudimentary water system capital cost.

WASA recently acquired a computer-based optimal network design program that will allow optimum design and will also increase efficiency. An additional issue related to water consumption is the assumption that users will abandon traditional rainwater catchment after the rudimentary water system is installed. However, according to the Knowledge, Attitude, and Practice⁹ study, in many cases, due to the preference for rainwater, users have not abandoned rainwater catchment systems. In general, the option of cost-effective improvements to rainwater systems has not been considered and should be explored.

Sewerage Systems

Belize City and Belmopan are the only two municipalities that have sewerage systems. A system is under construction in San Pedro. Treatment is provided by WASA. The Belize City sewerage system only covers approximately 60% of the city. There are currently 4,567 sewer connections in Belize City representing about 65% of the total potential users. This relative low coverage is believed to be due to absentee property owners or due to housing under construction.

The Belize City sewerage system is made up of conventional sewers in 15 sewer zones, each with its own central pumping station. The sewers are thought to be in good condition but many are below the groundwater table and some degree of infiltration is likely to occur (such as inflow through manhole covers). User-related problems are linked to clothing discarded in sewers, grease not adequately intercepted, and inflows through private clean-outs. The smaller pumping stations are operating well but there are occasional equipment problems at the larger stations.

Sewage treatment facilities comprise two facultative lagoons situated south of the city. Treated effluent is discharged into canals cut through a mangrove wetland which discharge into the Sibun Bight. The lagoon cells operate in series and are designed to provide 10 days hydraulic retention time each, although actual retention time could be double this period in the dry season. Early problems in the lagoons included premature corrosion of chambers and weed growth. However, the lagoons are generally in good condition, providing some 80 - 85% biological oxygen demand removal.

In Belmopan, the sewerage system and treatment works were inherited by WASA from the Belmopan Reconstruction and Development Corporation without any records, drawings, or operation manuals. The system comprises of sewers draining to two pumping stations which pump to a treatment plant. The treatment involves sedimentation tanks only, with the effluent discharging into the Belize River. Not all the meters and pumps are working and the treatment plant is partly bypassed, resulting in a biological oxygen demand removal rate of about only 5%. A study for the improvement of the plant recommended that a lagoon be built, but the construction has not been started. Currently, the plant is a potential health hazard because of fecal contamination of the Belize River and, hence, the improvements should be carried out as soon as possible.

Septic Tank Systems

Septic tanks are mainly used in urban areas and their construction is the responsibility of each household. The Public Health Bureau of the Ministry of Health, the Ministry of Housing and Urban Development, and WASA, all have their own standards for septic tank design. They are responsible for supervising that this infrastructure is built according to the appropriate standards. Developed by WASA, the Statutory Instrument No. 29 (1982) known as the Water and Sewerage Plumbing Code is the most complete. In some areas, the soil permeability characteristics and high water tables make soakage of septic tanks effluent difficult, resulting in groundwater contamination, backing up of waste into homes, and discharge of fecally contaminated waste into drainage canals. Given these conditions, there is a general impression that the construction of septic tanks is of a low standard, with usually one chamber and no baffles. In order to avoid these problems or to reduce them to a minimum, it is suggested that only one institution be held responsible for overseeing the compliance with standards.

Latrines

Ventilated improved pit (VIP) latrines are used for excreta disposal by 19% of households. Pour-flush or composting latrines are not commonly used. The first-time provision of latrines is usually through the Rural Water and Sanitation Programme. Under this program, the government provides materials and the local community provides labor. Each family is responsible for the construction of the superstructure. Depending on use and the level of the water table, the pit latrines have an average life span of five years.

Water Quality

Water quality delivered through the piped systems in the urban areas is adequate based on regular testing carried out both by WASA and the Public Health Bureau laboratories. Water quality delivered through the rudimentary water system is not monitored on a regular basis, therefore, the quality of water provided by these systems is not guaranteed. Due to the hardness of groundwater supplies from limestone aquifers, many families, in rural areas in particular, prefer rainwater over water from hand pumps or open wells. This is a safe source if adequate care is taken with collection and storage, but could be a source of contamination if collection areas are not clean and storage containers are not properly protected.

Water quality monitoring is performed by three governmental organizations: The Public Health Bureau of the Ministry of Health, WASA of the Ministry of Natural Resources, and it was proposed that the Department of the Environment of the Ministry of Tourism and Environment assume some responsibility. The Public Health Bureau analyzes samples from wells with hand pumps and, by request, analyzes river samples. WASA focuses its investigation on water delivered from plants and its effluents.

According to a recent groundwater analysis¹⁰, most of the groundwater is relatively free of contamination. The geometric mean fecal coliform was determined at 0.4 per 100 ml. The median pH of 6.8 is well within the range for groundwater. Nitrates are of some concern, but based on the data, do not pose an immediate threat except perhaps for the villages of Copper's Bank, Cristo Rey, Paraiso, San Pedro in Corozal, and Louisiana in the Orange Walk district. The presence of chlorides is high in the coastal area which indicates salt water intrusion and, quite possibly, indicates contamination in those areas that are noncoastal. This baseline study will be the starting point for a groundwater monitoring program.

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