The Water Utilities Corporation laboratory is committed to providing customers with accurate and cost effective laboratory services that in turn meet and/or exceed the expectations and requirements of its growing list of valued and satisfied customers. Analyses are performed by a professional team of chemists, microbiologists and laboratory technicians trained in the use of state-of-the-art analytical instrumentation. The laboratory employees realize the need for high quality data and recognize the impact that such data has on the key decisions made by our diverse list of customers. Employees undergo thorough competency assessments and continuous training on laboratory techniques, methodology, quality assurance, sample handling, documentation and reporting requirements based on a laboratory quality management system.
The laboratory provides analysis of water and wastewater sample matrices using various analytical methodologies and instrumentation. To ensure quality, standards are maintained; the laboratory participates in proficiency testing schemes and is accredited by Southern African Development Community Accreditation Service in accordance with ISO/IEC 17025: General requirements for the competence of testing and calibration laboratories. A comprehensive water quality database is maintained on a Laboratory Information Management System (LIMS).
The primary objective of laboratory’s quality management system is to produce quality data which is of known precision and accuracy which in turn ensures that such data can be relied on to represent the “true value” for a given sample. When extended to the field sampling process, the data accurately represents the larger volume from which the sample was originally taken.
MAIN OBJECTIVES OF MONITORING
The main objectives of water quality monitoring are:
- qualitative and quantitative evaluation of water quality by continuous verification of the water quality correspondence to relevant regulatory standards (compliance to national drinking water specification, BOS 32 and wastewater standard, BOS 93)
- verification of observation of prescribed limits for water abstracted from the water body and discharge of polluting substances in wastewater.
- verification of efficiency of water treatment processes
- interpretation of long-term trends in the water pollution level fluctuations, and demonstration of attainment of prescribed water-protective goals
- provision for advanced warning about emergency pollution and overshooting prescribed limits.
- identification and evaluation of water quality problems, e.g. detection of toxic substances in surface and ground waters.
The laboratory, located at the Mmamashia Water Treatment Works in Mmamashia, 1.8 km off Gaborone – Francistown A1 road, has 18 staff members currently performing laboratory analyses of:
|Total Dissolved Solids Total Phosphorus||Color Total Orthophosphate|
|Chemical Oxygen Demand (COD) Total Volatile Solids||Chloride Total Suspended Solids|
|Fluoride Calcium and Total Hardness||Ammonia Sulfate|
|Total coliforms||Faecal streptococci|
|Escherichia coli||Heterotrophic Plate Count|
|Faecal coliforms||Clostridium perfringens|
Cryptosporidium and Giardia
The following equipment is available for the various analyses:
|pH meters||Electrical Conductivity meters|
|Chlorine meters||Turbidity meters|
|Ion Chromatographs||Mercury Analyser|
|ICP Optical Emission Spectrometer||GC Mass Spectrometer|
Laboratory Analyses Fees
The following costs have been calculated and established in alignment with the current regional market prices of laboratory analysis. The revised costs are intended to recover costs of routine laboratory reagents, capital investment on equipment, instrument maintenance costs and general laboratory overheads.
A. Individual Analysis Costs
|ANALYTE||COST (P)||ANALYTE||COST (P)|
|Biological Oxygen Demand||76.90||Manganese||40.00|
|Chemical Oxygen Demand||107.65||pH & Temperature||43.55|
|Conductivity & Total Dissolved Solids||43.60||Sodium||40.00|
|Cryptosporidium and Giardia||3 221.90||Total coliforms||117.40|
|Escherichia coli||117.40||Total Hardness||59.85|
|Faecal coliforms||79.00||Total Suspended Solids||173.21|
|Free Chlorine||29.65||Vibrio cholera||165.00|
|Heterotrophic Plate Count||322.00||Zinc||40.00|
B. Group Costs
|TYPE OF ANALYSIS||PARAMETERS||COST (P)|
|Drinking Water for human consumption||pH, turbidity, conductivity, total dissolved solids, Escherichia coli, faecal coliforms, faecal streptococci, total coliforms, free chlorine, total chlorine, anions and metals.||1,566.40|
Drinking water for livestock
|alkalinity, pH, turbidity, conductivity, total dissolved solids, faecal coliforms, total coliforms, Heterotrophic Plate Count, anions and metals.||1,688.45|
|Water quality for irrigation||pH, conductivity, total dissolved solids, suspended solids, Escherichia coli, faecal coliforms, anions and metals.||1,390.15|
|Wastewater||pH, temperature, dissolved oxygen, biological oxygen demand, chemical oxygen demand, turbidity, conductivity, total dissolved solids, faecal coliforms, total coliforms, ammonia, free chlorine, total chlorine, anions and metals.||1,637.65|
|New connections to existing WUC network||Escherichia coli, free chlorine, total chlorine, total coliforms and turbidity||293.95|
|Treated Water Check||Conductivity, total dissolved solids, iron, manganese, turbidity, free chlorine and total chlorine||221.15|