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Sanitary facilities are poorer. Almost half of the households in Ngamiland and Chobe do not have
access to a toilet facility (own or communal). Just over ten percent has a flush toilet and almost thirty
percent has a pit latrine; the remaining ten percent uses a communal facility. Sewage systems (with
oxidation ponds) exist in Maun and Gumare. Shakawe is planned to have a sewage system in future.
Therefore, most wastewater will be collected in septic tanks. The District Council empties septic
tanks, but access to sanitation facilities is considered to be dismal (Plantec Africa et al. 2006, p. 130).
Household waste is typically dumped and burned in a rubbish pit (63%). Only 10.9% of the waste is
regularly collected. The rest is dumped along the roads or incinerated.
Most lodges have a system of septic tanks and soak away. The Prison in Maun has water treatment
schemes whose outflow is used for irrigation. The outflow of the treatment works in Maun is unlikely to
affect the wetland as it is located south of the wetland.
Tourism camps, village septic tanks and uncontrolled waste disposal are considered to be the largest
pollution risks.
Pollution estimates
Regarding domestic wastewater generation, water consumption for house and yard connection were
estimated using average water consumption figures. It was assumed that:
• Houses with a house connection would return 80% of their water consumption. In Maun and
Gumare, 90% of that would flow into septic tanks and 10% into wastewater treatment works.
In other villages all water would flow into the septic tank and soak ways.
• Houses with a yard connection would use pit latrines, and not generate overflow from septic
tanks.
The estimated amount of generated effluent through WWTW and septic tanks would be in the order of
0.6 Mm 3 per annum. It is difficult to estimate how much ends up in the wetland (if any). We have used
the rough population weight and a wetland entry weight to estimate the effluent that might end up in
the wetland and be cleaned. The closer one is to the wetland and the wetter the area is, the higher
the risk of effluent filtering into the wetland. Therefore, it was assumed that 40% of the effluent from
the panhandle could end up in the wetland and nothing from the rarely flooded areas. The areas with
a different flood regime would have a percentage in between the minimum and maximum.
At present, there are sixty-two camps in and around the wetland with an estimated total of around four
hundred room and eight hundred beds (source: ODMP data base). Most camps get water from the
river/lagoons or from well and boreholes where camps are further away from surface water. Camps
typically have septic tanks and soak ways, posing some danger of nitrogen and phosphate pollution.
DWA did assess the water quality around camps in 2003, but the results are not yet available.
According to DWA, there is need for more extensive and regular monitoring. Pollution may also occur
from car washing and maintenance and solid waste. In principle, organic waste is usually
decomposed in a pit, while other waste is burnt or returned to Maun. A review of the Camp inspection
visits (source: ODMP data base) show regular violations of lease agreements and sub-standard
waste disposal. Sub-standard waste disposal increases the risks of pollution of the wetland and its
water resources. Car maintenance and (used) oil sites were often not bunded, increasing the risks of
oil entering the wetland. Moreover, waste disposal in the camp and workers quarters was often found
to be inadequate. It must be emphasized that management practices vary widely from camp to camp.
An estimate was made of the wastewater from camps (tourists and workers). Assuming an average
bed occupancy rate of 40%, over 110 000 overnights would annually occur. Camp-based
employment, including guides, is estimated to be two hundred and fifty. Assuming a daily water
consumption of 70 litres/tourist/day and 16.5 litres/worker/day, the total water annual consumption
would be 9 450 m 3 .
Cost of wastewater treatment
Treatment costs have been estimated from the NMPSWW (SMEC and Sinham 2003) and based on
the average of the treatment costs of Maun and Gumare (i.e. P 6/m 3 ).
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