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Petrus Venter Deputy Director: IWRM & CS Crocodile (West) Marico WMA. H ARTBEESPOORT D AM INTEGRATED BIOLOGICAL REMEDIATION PROGRAMME:. Finland June 2010. www.dwaf.gov.za/harties. Scope. Hartbeespoort Dam 1 of 9 Hypertrophy in RSA 7 of 9 in Crocodile Marico Catchments. ●.
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Petrus VenterDeputy Director: IWRM & CSCrocodile (West) Marico WMA HARTBEESPOORT DAM INTEGRATED BIOLOGICAL REMEDIATION PROGRAMME: Finland June 2010 www.dwaf.gov.za/harties
Scope Hartbeespoort Dam 1 of 9 Hypertrophy in RSA 7 of 9 in Crocodile Marico Catchments ●
What does Hartbeespoort Dam look like ?
Problem Statement • 700+ Mega Liters of purified sewage p/d • 280+ tons of phosphate p/a. • Depleted riparian variation & in-stream habitat • Shrinking wet lands • Toxic microcystis algal blooms • Exotic water plants (Hyacinths) • Exotic fish (Carp, Babel, Canary Kurper) • Distorted food web and fish population • Depleted diversity in catchment & dam • Impacts from Desertification / Social Drought
ADRESSING GLOBAL WARMING AND DESERTIFICATION THROUGH IMPLEMENTING IWRM Harties metsi a me programme www.dwaf.gov.za/harties
DESERTIFICATION - PROBLEMS OR SOLUTIONS? A Global of Local Threat? www.dwa.gov.za/harties
Sahara Dessert Middle East Kalahari Dessert South pole
Sustainable development !? • How well do we balance development and environmental protection in 21st century? • Do the world do better with Sustainable development comparing with 100 years? • What are the collective impacts resulting from modern day Civilization? Agriculture; Urbanisation; Mining and IndustryBuild on fossilized customs?
Environmental Impacts culminate inDesertification. • What is a desert ? How can it be defined? • Environmental conditions that occur in arid and desert like environments: • Vegetation: Little to none, occasionally & small • Soil: Exposed rock & sand • Air: Extreme temperatures,Heat wavesdestroy life / vegetation, prevent rainfall • Water: Little to non rainfall,, quick run off / seepage, quick evaporation vs slow transpiration • Biosphere: Depleted diversity
2 500 000 ha 135 000 ha
197325 000198710 00020011 350sq km Lake Chad
Desserts vs. Forests • Desertification: Sahara 1000 - 6000 yr - 8,6 mil sq km Kalahari / Karoo - oldest ? - 0.26 mil sq km • Deforestation: > 5 mil ha/a pristine rain forests destructed > 13 mil ha/a impacted rain forests destructed > 30 mil ha/a vegetation destructed for agriculture, urban, mining & industry ?
Desserts vs. Forests • Deserts = little to non vegetation > create deserts • Forests= maximum vegetation > create forests
Function of Vegetation Absorb preserver heat HEAT ENERGY ORGANICS Photosynthesis
Function of Vegetation Shadow – Cool soil reduce evaporation Create micro-climate
Function of Vegetation & Organics Create micro climate that sustain environmental water balance & retention / sponge effect
Increase water ingress & water retention Function of Vegetation & Organics Retain Moisture & Fertilise Soil
Block Heat Waves, Wind & Evaporation Function of Vegetation & Organics
Sustain bio-diversity Life conditions for extended food web Function of Vegetation & Organics
URBANISATION Hard surfaces: roads, roofs, buildings Exposed soil: sand and rock Quick storm water run off, little infiltration Little vegetation Extreme temperatures, air-conditioning? Effect of Civilization &Developments
AGRICULTURE Industrial revolution: trees to plowing Vegetation depleted, occasional monocultures, irrigating desert conditions Biggest user of water: evaporation Exposed soil: sand and rock, quick run off Ever growing hard surfaces: infrastructures Over grazing, veldt fires Quick storm water run off, less infiltration, more evaporation and less transpiration More extreme temperatures Effect of Civilization/ Developments
Impact - erosion & part of the gabions which have been washed away due to high flows – Clayville wetland
DESTRUCTION OF RIVERBANK AND RIPARIAN VEGETATION AT THE CROCODILE RIVER HBPD
MINING & INDUSTRIES Ever growing hard surfaces: infrastructures, Sand dams, Rock dumps Quick storm water run off, little infiltration, more evaporation Little vegetation Extreme temperatures, air-conditioning Effect of Civilization/ Developments
Pilot Projects & Implementation Cases Water Use Efficiency + multiple water use Waste minimization, recycling & reuse Enhance groundwater recharge Current implementation sites: Impala platinum mine Other Platinum mine Harties, metsi a me
Implats: Super Compost from wastes: Woodchips and Sewage Impala Platinum Case Study
DWAF Authorisation From 2002 integrated water and waste management were require according to NEMA & WSSD – waste minimisation and recycling Stipulate minimum rehabilitation in line with improved / more efficient water use – improve soil/moisture content with organics
Environmental Challenges Sewage material potentially hazardous Leaching of heavy metals High salt concentrations Anaerobic conditions – smells, health hazards (patogens) Treatment & disposal cost Long term liability costs Considered as nuisance and waste product – highly regulated
Woodchip Case Study Woodchip stockpiles and waste sites have environmental impacts Leaching of nitrogenous compounds Al toxicity if low pH experienced No beneficial use Great costs incurred to stockpile and transport and dispose woodchips Legislation will not permit disposal of valuable organic “waste materials” (CMS) Waste Recycling Management
Integrated Environmental Management Combine the organic waste materials Process: Mix to a predetermined ratio Put it through a composting process Watering Ventilation Earthworms Stockpile