Chapter 6: Water Resources

 Water Resources

 6.0 Introduction

Malawi is generally rich in water resources which are stocked in its lakes, rivers and aquifers (DREA, 1994). While commendable progress has been made in the development of water resources, there are environmental issues that the country should address as a matter of urgency in order to conserve resources from further depletion and degradation. Factors that contribute greatly to the depletion and degradation of water resources in Malawi include poor management of catchment areas, environmentally unfriendly agricultural practices, rapid population growth, inappropriate discharge of industrial wastes and the weak institutional structures for enforcing the Water Resources Act.

The degradation of catchment areas and marginal lands as a result of population pressure and inappropriate agricultural activities, has accelerated excessive loss of soils, resulting in sedimentation problems such as those experienced in the Shire and many other rivers. It has also led to the reduction of base flows and increased incidences of flood disasters during heavy storms. Inadequate sanitary facilities for human settlements, particularly those established in catchment areas, coupled with agrochemical runoff, have led to the deterioration of the quality of water resources particularly in rivers that flow through the cities of Blantyre and Lilongwe. It is therefore absolutely necessary that corrective measures such as economic diversification, conservation of catchment areas and control of population growth implemented urgently in order to conserve water resources for the benefit of the present and future generations. To attain this noble goal, it is imperative that institutions with the mandate to manage water resources in Malawi are given all the necessary support from the government, especially in the areas of law and finance to support the implementation of projects related to water resources development.
  6.1 Pressures on water resources

The following are some of the pressures that are being exerted on water resources in Malawi: 

  • Inadequate water resources for domestic consumption due to increases in population growth, which has by far exceeded the capacity of originally designed water supply schemes. (see Fig 6.1)
  • Increased demand for water resources for industrial production with the rapid growth of the industrial sector.
  • Increased demand for water for crop irrigation as more and more irrigation schemes are being established.
  • Increased sedimentation in rivers, lakes and reservoirs as a result of soil erosion taking place in catchment areas.
  • Discharge of untreated or partially treated industrial and domestic wastes into water bodies especially in rivers that flow through cities e.g. the Mudi and Chitawira rivers in the City of Blantyre.
  • Encroachment of agricultural activities and settlements on catchment areas and marginal lands.
  • Frequent occurrences of droughts initiated by the El Nino and Southern Oscillation (ENSO) phenomena.
  • Potential impacts of climate change on water resources as the general circulation models predict an increase in temperature of 2.5-4.7 °C by the year 2075, although precipitation results show more variability with global warming.
  • Infestation of water bodies by invasive plants such as the water hyacinth.

  6.2 The state of water resources in Malawi

The state of water resources in Malawi may be described by the following statements, which are a direct response to the pressures outlined above:

  • Declining amounts of water resources to meet the demand for domestic needs, industrial production and irrigation requirements.
  • Declining flow depths in river channels and reduced depths of reservoirs due to sedimentation.
  • Declining amounts of both surface and ground water due to inadequate rainfall in catchment areas.
  • Reduction in base flows due to increased surface runoff resulting from depletion of vegetation cover.
  • The deterioration of water quality in rivers especially those flowing through the cities of Blantyre and Lilongwe and the municipality of Zomba.
  • Pollution of both surface and ground water resources due to excessive use of agrochemicals in catchment areas.
  • Increased frequency of floods and droughts, possibly resulting from climate change factors.
  • Proliferation of water hyacinth in water bodies especially the Shire River.
  6.3 Description of water resources

Water resources in Malawi can basically be classified into two broad categories namely surface and groundwater resources. Surface water resources comprise all water bodies that are found above the earth's surface whereas groundwater resources are found in aquifers and fracture zones.

All water resources in Malawi are replenished by rainfall in catchment areas and on the surface of the water bodies in the case of surface water resources and in recharge areas for groundwater resources.

6.3.1 Malawi's surface water resources 

Surface water resources in Malawi comprise of a network of river systems such as the Shire, Songwe, Ruo, Bua, Linthipe, Lilongwe, Rukuru and lakes such as Lake Malawi, Lake Chilwa, Lake Chiuta and Lake Malombe. Total runoff as a percentage of the water resources areas are presented in Table 6.1. It is apparent from the table that all along the lakeshore, the percentage of runoff is generally high. Rivers draining the Mulanje Massif also have high percentages of runoff.

Lake Malawi

Lake Malawi, with a surface area of about 28760 km2, has a great influence on the water balance. The mean annual rainfall over the lake is estimated to be 1549 mm. The total inflow into the lake is calculated to be 920 m3/s out of which 400 m3/s is from Malawi, 486 m3/s is from Tanzania and 41 m3/s is from Mozambique.

The highest monthly outflow of 963 m3/s occurred in May, 1980. Hydrometric data also show that the Shire stopped getting outflow from Lake Malawi for a period of 22 years from 1915 to 1937 (Kalua et al, 1997). The mean lake level is 474.4 m above sea level (Fig 6.2) and the average annual outflow is estimated to be 395 m3/s. The highest annual outflow of 825 m3/s and 820 m3/s occurred in 1979 - 80 and 1980 - 81 respectively.

Lake Chilwa

The catchment area of Lake Chilwa is estimated to be 500 km2. Most of the rivers that drain their water into Lake Chilwa arise from the northern slopes of the Zomba and Mulanje Massif. All the rivers are perennial in their upper reaches but gradually lose their flow in the Chilwa - Phalombe Plains due to the porous nature of the area.

Surface water quality

Where catchment areas have been extensively cleared for agricultural purposes, river flows have been affected significantly. In some cases flow during the dry season completely stops. The Bua and Thangadzi East are examples of rivers whose base flows have been lost. They have no water flow during the dry season.

The quality of surface water resources in Malawi is also affected by other factors like the chemical composition of parent rocks, agricultural activities and the discharge of effluents including the disposal of wastes from residential areas and industrial sites. The chemistry of the vast majority of surface water resources is characterized by alkaline earth dominance in the caution group; and by the carbonate system in the anion group. Most of the surface waters can be classified as soft to moderately soft i.e. hardness less than 100 mg/l of calcium carbonate. The total dissolved solids content values are generally less than 100 mg/l. The occurrence of droughts has been associated with increased mineralisation in river waters.

Since Malawi's economy is largely dependent on agriculture, vast expanses of land are cleared every year for agricultural production. This practice encourages soil erosion, which leads to sedimentation problems and the prevalence of turbid waters observed in rivers and reservoirs (Fig.6.3). It has been noted that there is a general increase in the content of suspended solids in rivers such as the Shire and North Rukuru. Runoff from estates contain agrochemicals which pollute surface water resources, especially rivers and reservoirs.  The bacteriological quality of rivers, especially those flowing through the cities of Blantyre Lilongwe, Zomba and Mzuzu is generally poor due to effluent discharges. Counts as high as 20,000 faecal coliform per 100 ml have been observed in Lilongwe River downstream of the sewage plant during periods when the plant has broken down. In low-income areas of the above cities, pit latrines are usually constructed without consideration to their potential for water resources pollution.

6.4.2 Groundwater resources

Development of groundwater resources has been primarily for drinking water supply for both rural and peri-urban areas. This supply has steadily increased as reflected by the number of boreholes drilled between 1992 and 1996 (Fig.6.4).

There are two types of aquifer systems in the country associated with ground water recharges, namely the extensive but low yielding weathered basement aquifer of the plateau area and the high yielding aquifer of the lake shore plains and the Lower Shire Valley.

The prolonged in situ weathering of the crystalline basement rocks has produced a layer of unconsolidated saprolite material and it is this which forms an important source of groundwater for rural domestic requirements. The average yield in the weathered zone of the basement complex lies in the range of 1 - 2 litres per second.

The alluvial aquifers are fluvial and lacustrine in nature, and highly variable in character both in vertical sequence and lateral extent. They occur in several basins which apart from Lake Chilwa are all located along the rift valley floor: Karonga Lake Shore, Salima - Nkhotakota Lake Shore, Upper Shire Valley and the Lower Shire Valley. Most lithological records from boreholes give little detailed information about the successions.

The sedimentary environments likely to produce the highest groundwater yields are buried river channels and littoral zones of the lakeshore where the deposits are usually coarse "rained and well sorted. The Lake Chilwa Basin is different from the other alluvial areas as it is perched on the eastern side of the rift valley. The lithological logs of boreholes located in this area suggest that much of the succession is clayey. In the alluvial aquifers yields greater than 20 litres per second have been obtained.  Groundwater resources in the basement aquifer are characterized by the dominance of alkaline earth in the caution group and by the carbonates in the anion group. Total dissolved solids content values are generally less than 1000 mg/I and typically around 350 mg/l. On the other hand groundwater in the alluvial aquifers is more mineralized than in the basement aquifers. The inferior quality of water drawn from hand dug wells is a direct result of the following factors:

  • shallow groundwater tables usually less than 2m, with seasonal fluctuations that bring them close to the ground surface where water are easily polluted;

  • faecal contamination since dambos are extensively used for grazing and watering of livestock all the year round; and.

  • poor siting of water points since dug wells are sometimes located very close to traditional water sources which are always open and invariably grossly polluted.
6.4.1 Policy and legislation

The National Water Resources Management Policy developed in 1994 outlines the policy and strategies for water resources management in Malawi. Salient features of the policy are as follows:

  • water should be managed and used efficiently and effectively in order to promote its conservation and future availability in sufficient quantity and acceptable quality;

  • all programmes related to water should be implemented in a manner that mitigates environmental degradation and at the same time promotes enjoyment of the asset by all beneficiaries;

  • water allocation should recognize that water is not only a social but an economic asset, and in a manner that achieves maximum benefit to the country;

  • investment of public funds in water and related programmes should be guided by the expected net economic, social and environmental benefits of the programme to the country as a whole;

  • in planning and providing water services, consideration should be given to safe disposal of the resultant waste water;

  • the government shall facilitate the participation of stakeholders in water management programmes (including users and special target groups) both in the public and private sectors to ensure that the needs of their relevant interests are taken into account; and

  • the pricing of water should reflect demand and the cost of water services. Pricing should aim at the reduction of government financial support to the sector over time.
While the policy addresses all matters pertaining to the provision of water services, it is silent on issues related to water resources conservation such as catchment protection and rain water harvesting. Therefore there is need to incorporate these issues in the policy. Other aspects not covered by the policy include regional/international commitments i.e. cooperation between Malawi and its neighbouring countries on shared waters; research, disaster preparedness (both floods and droughts); and monitoring and evaluation of water resources.

The enforcement of laws governing water resources in Malawi rests with the Water Resources Board. These laws are outlined in the Water Resources Act along with other regulations such as Pollution Control. The Act provides for the granting of water rights such as diversion, storage, abstraction and use of public water in specified quantities. Under the Act, the Minister responsible for water resources is empowered to punish all users of water that contravene the regulations. To ensure that the Water Resources Act is complied with by all users of public water resources, the Board has been entrusted with authority to monitor the adherence to water regulations without discrimination.

Although the Act calls for the implementation of punitive measures against users that contravene the regulations, the Board has been seen to be ineffective in punishing offenders and conducting monitoring works. For example, no punitive measures have been taken against people who have opened maize gardens in the water catchment areas such as the Mudi catchment in Makheta. It is therefore imperative that the government should ensure that the Board is supported in carrying out its tasks if water resources are going to be conserved from further depletion and degradation.

6.4.2 Institutional framework

The water sector in Malawi comprises several levels of responsibility that range from national policy management to the construction, operation and maintenance of water supply and water borne sanitation services at the user level. These levels of responsibility are assigned to different government institutions and parastatal organizations. The Ministry of Water Development is the key government institution responsible for water management services and consists of four major sections namely the Hydrology, Hydro-geology, Rural Water Supply and Sanitation, and the Water Quality Sections. Other important organisations in the management of water resources in Malawi are the Water Resources Board, Blantyre Water Board, Lilongwe Water Board, Northern Region Water Board, Central Region Water Board and Southern Region Water Board.

The Hydrology Section is also responsible for the collection, processing, analysis, archiving and dissemination of hydrometric data. The section operates 171 gauging stations throughout the country. Data collection has been going on since 1896. The major constraint in the collection of hydrometric data is the poor state of equipment used at the gauging stations.

The Hydrogeology Section is responsible for monitoring, assessment, management and exploration of groundwater resources. However, the Section is almost exclusively engaged in borehole construction and borehole maintenance activities. Groundwater monitoring, assessment and management are therefore basically non-existent. At present there are more than 13,000 boreholes countrywide.

Up until 1996 the provision of water supplies outside the cities of Blantyre and Lilongwe was the responsibility of the Water Department through the District Water Supply Fund and the Rural Gravity Piped Water Supply Schemes. This responsibility now rests with the Regional Water Boards whereas the rural gravity piped water schemes and groundwater schemes remain the responsibility of the Rural Water Supply and Sanitation Section of the Ministry of water development.

The Water Quality Section is responsible for monitoring and assessment of the physical, chemical and biological aspects of water quality. The Section also conducts inspections on pollution levels in effluent and wastes discharged in public waters. The major setback to the assessment of water quality is the inadequacy of laboratory equipment for conducting the analyses, inadequate training for the laboratory staff and an acute shortage of equipment for use in water sampling programmes.

As stated earlier, the Water Resources Board oversees water resources management policies as outlined in the Water Resources Act and other regulations. Furthermore, the Board collaborates with other institutions responsible for environmental monitoring and control on water resource management issues. The Water resources Board comprises of the following: the chairperson, the Secretary for the Ministry of Water Development, the Secretary to the Office of the President and Cabinet, a representative from the Water Resources Division of the Ministry of Water Development, the secretary responsible for Commerce Trade and Industry, the Chief executive of the Electricity Supply Commission of Malawi and four other members representing the public.

6.4.3 Research

Very little research work has been done in the water resources sector in Malawi and this is a matter of concern. Attempts were made in the early 1990s to establish a research unit in the Ministry of Water Development within the Hydrogeology Section but the project did not take off. It is therefore not surprising to note that most of our water resources problems remain unresolved e.g. sedimentation control of rivers and reservoirs, and limited knowledge and understanding in rainwater harvesting.

The Polytechnic is currently conducting research on the use of molinga seeds as a coagulant in water treatment plants. This study is carried out at the Thyolo Water Supply Treatment Plant in collaboration with Leicester University. Another study that is also being conducted by the Polytechnic is the use of molinga seed husks as activated carbon for odour removal. This study is done in collaboration with Edinburgh University. More research is needed to address the many water-related problems the nation is currently facing. 

6.4.4 Technology development and transfer

Most of the technologies used in water resources management in Malawi are foreign. However, this does not imply that there is absolutely nothing that the country has achieved in this sector. Successes worth mentioning are the development of the Mark 5 shallow well hand pump and the popular Maldev borehole pump which was later modified in Kenya and renamed the Afridev. Work on the development of the Maldev was initiated by experts from the British Geological Survey in the early 1980s while working on the Livulezi Valley Integrated Groundwater Project in Ntcheu. The development of the Mark 5 shallow well pump was carried out under the UNICEF funded Wells Programme during the same period. These projects were initiated by the need to have pumps that would be locally manufactured and fitted on water points. The development of the easy to install and repair pumps has rendered the Maldev and Mark 5 pumps obsolete. Popular hand pumps such as the Nira and Afridev find wide applications on hand-dug wells and boreholes respectively. The specifications for Afridev hand pumps were adopted as Malawi standards against which all the hand pumps are quality certified by the Malawi Bureau of Standards. The simple technology involved in the assembly of these pumps has enabled the Ministry of Water Development to train the local community in the maintenance of the pumps through the Village Level Operation and Maintenance (VLOM) programme under the Ministry's Community Based Management (CBM).

The Ministry of Agriculture and Irrigation is developing the treadle pump with the assistance of Malawi Industrial Research and Technology Development Centre as a potential water-lifting device for purposes of crop irrigation.

6.4.5 Education, awareness and communication

There are only a few areas in water resources management where aspects of education, awareness and communication find application. One such aspect is the provision of water services, especially to the rural community, where it has become absolutely necessary to furnish the communities with information on public health issues in order to curb the prevalence of water born and water related diseases. This is usually done during the course of project implementation. The local community is also encouraged to participate in all the stages of project implementation. This has proved invaluable in instilling in the mind of the beneficiary community a sense of ownership of the water projects, hence projects constructed under such circumstances are usually properly looked after. Through its CBM Programmes, the Ministry of Water Development still continues to conduct these training sessions in the provision of rural water supply schemes.

Several programmes continue to be aired on the national radio, which aim at sensitizing the community to protect catchment areas from encroachment by agricultural activities and human settlements. One such programme is "You and the Environment" which is sponsored by the Environmental Affairs Department. In addition to the radio programmes, the Ministry of Water Development also conducts awareness campaigns on water resources in general to the local community serviced by specific water projects. The Water Boards have also made use of the radio to warn people against wastage especially during periods of acute water shortages.

The District Development Committees facilitate communication between the Ministry of Water Development and the community. The Participatory Rural Appraisal (PRA) approach has been a useful tool in this respect. Although it may not be possible for the rural communities to accurately analyze each choice - especially the technical aspects - they can at least assess their role in the project. The rural community is normally informed about the duties and activities that they are supposed to perform. The government is now encouraging the rural community to identify projects which they want implemented through a process known as the Demand Responsive Approach (DRA). This is a good procedure for project implementation as it enables the government to implement only those projects that the communities seriously need.

6.4.6 Water and land use planning 

The use to which land located in watersheds is put has a great bearing on the availability and quality of water resources. In this respect, it has been the responsibility of the government through the Water Resources Board to ensure that catchment areas are not utilized for agricultural production and human settlements. This issue is addressed by the Water Resource' Act which prohibits such activities from being carried out in catchments and also bars people from developing the area close to water bodies, at a distance less than 50 metres from the water body itself. But as stated earlier, gross violation of the Water Resources Act has led to the encroachment upon important catchment areas e.g. the catchment area for the Mudi River in Blantyre and several others in the country leading to sedimentation and water pollution problems.

6.4.7 Economic, fiscal and market related incentives

The Water Resources Policy gives a new dimension to the importance of water services in Malawi. This is especially true of rural water supply schemes where the provision of water services has always been considered free. The government has now been placed in a position where it facilitates the provision of these water supply schemes; and the local communities are given the responsibility to maintain them. Through annual contributions, the local communities are able to procure spare parts for borehole pumps or taps for maintenance purposes.

Due to spatial variation and seasonal variation in the occurrence of water resources and the growing competition for its use, water resources are being over utilised at the present level of development in some parts of the country. It is thus becoming necessary to allocate water resources in a manner that creates maximum achievable benefits. Hence it has become necessary to allocate water in accordance with two principles. Firstly, the provision of basic domestic needs to those that

can not afford to pay in cash or kind for the water services. Secondly, provision for resource management and environment i.e. allocations should be reserved to ensure the sustainability of each resource and for the conservation of the environment.

Since funds for investment in water and wastewater infrastructure are limited, it is prudent that only those programmes that yield great benefits to the country should be implemented. The approach recommended for programme selection consists of two steps namely the formulation of project proposals and need for implementing multipurpose projects. There has to be a systematic preparation of project proposals that the community finds acceptable for implementation in terms of the service offered and the associated costs; the projects shall contribute to the economic development of the nation and at the same time enhance the environment. Priority for project implementation should be given to those schemes that achieve multiple objectives in an optimum way with the available resources.

It is the government's intention to broaden coverage in the provision of water supplies while converting as many of the water supply schemes as possible into autonomous, commercially viable systems. The government intends also to reduce its share of financial support in the sector, while targeting the available support to those that can not afford to pay the costs of the service in cash or kind. However, a water pricing strategy is needed which will ensure that water pricing is perceived to be justified and fair. This may include providing incentives to encourage selection of cost effective investments in schemes which are: responsive to the demand of the users; providing incentives to the managers of the schemes to operate and maintain efficiently; and generating sufficient income from the scheme to cover costs and help ensure financial sustainability of the schemes.

The Water Services Sector Study has suggested that the rural community could be asked to pay a minimum of MK 5.00 per year per household as a contribution towards the general maintenance of water supply schemes. The overall conclusion on affordability is that the urban poor can not afford the level of water services being offered at present. It may therefore be prudent for the water sector institutions to introduce hand pumps or other appropriate low cost technologies in the fringe areas of towns.

The Water Sector Study further recommends that tariffs for water services in urban areas should be increased in line with inflation; and that the fall in water prices which has taken place over the last decade should be redressed. The implementation of the above recommen-dations will ensure the self sustainability of water supply schemes in the country. A summary of investments in the water resources utilisation is presented in Fig. 6.5(a) and Fig. 6.5 (b).

6.4.8 Implications for regional and global issues

In November 1996, SADC ministers responsible for water resources met in Pretoria - South Africa where they agreed to facilitate the integration of water resources management in the SADC Programme of Action and to optimize the contribution from water resources towards the economic growth of the member countries. This meeting led to the birth of the SADC Water Sector, based in Lesotho, whose task is to promote and advance the development of water resources in the region on the following terms of reference:

  • to facilitate integrated planning, development, management and equitable utilisation of water resources at both the national and regional level;

  • to mobilise resources (human and financial) for integrated planning, development, management and equitable utilisation of common water resources and the implementation of approved regional programmes; and

  • to promote joint and cross border water resources development investments and provide guidance on cost sharing arrangements.
During the meeting ministers also agreed to call for a Round Table Conference where member countries would present projects to co-operating partners and solicit additional technical and financial assistance for their implementation. It is in direct response to this requirement that the Ministry of Water Development is currently in the final stages of preparing the country situation report on water resources for submission to the Conference.

Another important regional programme in which Malawi is involved is the implementation of the Zambezi River Basin Action Plan i.e. the ZAC Plan, which will necessitate the formulation of water resources management principles for the Zambezi River Basin. This project involves all countries within the Zambezi River Basin namely Malawi, Mozambique, Zimbabwe, Zambia and Angola. 

Chapter References:

 Contents | Foreword  | Acknowlegdements | Editorial Process 
Contributors | Preface | Acronyms  | Overview
Chapters: | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | Appendix I
Lists: Maps | Figures | Tables | Boxes | References