The impact of the Thaba-Nchu sewage treatment plant on the freshwater ecology of the surrounding area
| dc.contributor.advisor | Du Preez, P. J. | |
| dc.contributor.advisor | Vos, A. T. | |
| dc.contributor.author | Koikoi, Likeledi Martha | |
| dc.date.accessioned | 2018-06-15T12:45:01Z | |
| dc.date.available | 2018-06-15T12:45:01Z | |
| dc.date.issued | 2013-06 | |
| dc.description.abstract | English: Thaba-Nchu is located about 62 km south-east of Bloemfontein, in the Free State Province of South Africa. Sepanespruit is a tributary of the Modder River which drains the Thaba- Nchu area. This area has a population of about 70 000 people and is served by one sewage treatment plant whose hydraulic capacity is 6 MI/day. This study was conducted to evaluate the effectiveness and the efficiency of the Thaba-Nchu sewage treatment works and the effects of the sewage effluent into the receiving stream; Sepanespruit. Sources of pollution into the stream were identified as the poorly treated sewage effluent, domestic wastes, urban litter and run-off, raw sewage, livestock and human trampling. The municipal truck tankers that disposed-off sewage at the manhole which connected to the sewage treatment plant polluted an area of about 30m in radius with raw sewage, the origin point being the manhole. A canal of raw sewage originated from that area and became a point source of pollution to Sepanespruit. The sewage effluent caused thermal pollution to the stream, bacterial contamination (measured as total coliform bacteria, faecal coliform bacteria and E. coli), and addition of excessive salts (measured as electrical conductivity (EC) and nutrients (PO4 3- and NH3). Pathogens that occurred in Sepanespruit water were E.coli, Shigella dysentriae, Faecal enterococci and Faecal streptococci; they are all of faecal origin. Endocrine disrupting chemicals such as dyes, herbicides, pharmaceutical and cosmetic compounds were also identified in the sewage effluent; the implication was that the conventional treatment processes did not remove those chemicals from the sewage stream. The sewage effluent was sometimes released in a red-brown coloured state. The colour was attributed to the rich dyes that a meat processing factory dumped at the sewage treatment plant. The most common algal divisions identified in Sepanespruit water were Cyanophyta, Chlorophyta, Bacillariophyta and Euglenophyta. The vegetation along Sepanespruit was classified using JUICE (the computer vegetation classification program) into one community of Paspalum dilatatum - Rumex crispus. Highly enriched water contributed to the observed vegetation structure; the stream banks were covered by monotypic stands of plant species that are adapted to disturbances such as Paspalum distichum and Rumex crispus. The canal water and sewage effluent were the major sources of point pollution to Sepanespruit. Poor sewage quality was a result of poor management, old non-functional unit processes and unskilled operational staff. The section of Sepanespruit that formed part of this study was deemed eutrophic but the dam water was oligotrophic because of the biofiltration process that the reed beds of Typha capensis and Phragmites latifolia undertook before water moved into the dam. Alternative methods of factory dyes disposal and sludge handling have to be sought in order to reduce water and environmental pollution. The waste management department of the water affairs has been advised to monitor disposal of sewage of sewage at the source manhole and rehabilitate the polluted area. | en_ZA |
| dc.description.abstract | Afrikaans: Thaba-Nchu is omtrent 62 km suid-oos van Bloemfontein in die Vrystaat Provinsie van Suid Afrika geleë. Sepanespruit is 'n sytak van die Modder River wat die Thaba-Nchu area dreineer. Die area het 'n bevolking van omtrent 70 000 mense, en word deur een riool behandelings-fasiliteit hanteer met 'n hidorliese kapasiteit van 6 MI/dag. Hierdie studie was aangepak om die effektiwiteit en doeltreffendheid van die Thaba-Nchu riool behandelingswerke te evalueer en ook die effek van die riool afvalwater in die ontvangende stroom-die; Sepanespruit. Bronne van besoedeling in die stroom was ge-identifiseer as swak behandelde riool afvalwater, huishoudelike afval, stedelike rommel en afvalwater, riool, vertrapping deur lewendehawe en mense. Die munisipale trenkwaens wat ontslae raak van riool by die stormwaterpyp wat met die riool behandelings-fasiliteit verbind het is, 'n area van ongeveer 30 m in radius met riool besoedel, met die stormpyp uitlaat as oorsprong. 'n Kanaal van riool het van daardie area ontstaan en 'n punt bron van besoedeling van die Sepanespruit geword. Die riool-afvalwater het termiese besoedling in die stroom veroorsaak, bakteriële kontaminasie (gemeet as totale coliform bakterieë, fekale coliform bakterieë en E. coli), en die byvoeging van oormatige soute (gemeet as elektriese geleiding (EC) en voedingstowwe (PO4 3- en NH3). Patogene soos E. coli, Shigella dysenteriae, Faecal enterococci en Faecal streptococci wat hoofsaaklik in Sepanespruit se water voorkom, is almal van fekale oorsprong. Chemiese ontwrigtende stowwe sooskleurstowwe, onkruiddoders, farmaseutiese en kosmetiese stowwe was ook ge-identifiseer in die riool afwalwater; dit dui daarop aan dat konvensionele riool behandelings prosesse nie hierdie stowwe uit die riool stroom verwyder het nie. Die riool afvalwater is soms vrygestel met 'n rooi-bruin kleur. Die kleur word toegeskryf aan die sterk kleurstowwe wat deur 'n vleis-verwerkings-fabriek in die riool behandelings fasiliteit gestort was. Die mees algemene alg groepe in Sepanespruit sluit in Cyanophyta, Chlorophyta, Bacillariophyta en Euglenophyta. Die plantegorei rondom Sepanespruit is geklassifiseer d.m.v. JUICE (plantegroei klassifikasie rekenaar program) as een gemeenskap van Paspalum dilatatum - Rumex crisp us. Die hoogs verrykte water het bygedra tot die plantegroei struktuur; die stroom oewers was bedek deur monotipiese plantegroei van spesies wat hoogs aangepas is tot versteuring soos Paspalum dilatatum en Rumex crisp us. Monotipiese stande van besoedeling-aangepaste spesies soos Paspalum distichum was ook aangemerk. Die kanaal water en riool afvalwater was die grootste bronne van punt besoedeling van die Sepanespruit. Swak riool afvwalwater was die nagevolg van swak bestuur, ou niefunksionerende eenheid prosesse en onopgeleide uitvoerende personeel by die riool behandelings fasiliteit. Die deel van Sepanespruit wat deel van hierdie studie area uitmaak was eutrofies, maar die dam water was oligotrofies as gevolg van die bio-filtrasie proses wat deur riete Typha latifolia en Phragmites capensis uitgevoer word voor die water by die dam in vloei. Alternatiewe metodes om van die fabrieks kleurstowwe ontslae te raak en slyk hantering moet geimlementeer word om water en omgewings besoedeling te verminder. Die afvalbestuur afdeling van die munisipaliteit is veronsterstel om die verwydering van riool by die stormpyp te monitor en die besoedelde area te rehabiliteer. | en_ZA |
| dc.description.sponsorship | Government of Lesotho through the National Manpower Secretariat | en_ZA |
| dc.description.sponsorship | Inkaba yeAfrika | en_ZA |
| dc.description.sponsorship | Water Cluster, University of the Free State | en_ZA |
| dc.identifier.uri | http://hdl.handle.net/11660/8422 | |
| dc.language.iso | en | en_ZA |
| dc.publisher | University of the Free State | en_ZA |
| dc.rights.holder | University of the Free State | en_ZA |
| dc.subject | Sewage effluent | en_ZA |
| dc.subject | Thermal pollution | en_ZA |
| dc.subject | Bacterial contamination | en_ZA |
| dc.subject | Monotypic vegetation | en_ZA |
| dc.subject | Eutrophic water | en_ZA |
| dc.subject | Oligotrophic water | en_ZA |
| dc.subject | Biofiltration | en_ZA |
| dc.subject | Freshwater ecology -- South Africa -- Thaba-Nchu | en_ZA |
| dc.subject | Sewage -- Purification | en_ZA |
| dc.subject | Freshwater ecology -- South Africa | en_ZA |
| dc.subject | Dissertation (M.Sc. (Plant Sciences))--University of the Free State, 2013 | en_ZA |
| dc.title | The impact of the Thaba-Nchu sewage treatment plant on the freshwater ecology of the surrounding area | en_ZA |
| dc.type | Dissertation | en_ZA |