Petrus VenterDeputy Director: IWRM & CSCrocodile (West) Marico WMA

www.dwaf.gov.za/harties

HARTBEESPOORT DAM INTEGRATED BIOLOGICAL

REMEDIATION PROGRAMME:

HARTBEESPOORT DAM INTEGRATED BIOLOGICAL

REMEDIATION PROGRAMME:

Finland June 2010

ScopeScope• Hartbeespoort Dam 1 of 9 Hypertrophy in RSAHartbeespoort Dam 1 of 9 Hypertrophy in RSA• 7 of 9 in Crocodile Marico Catchments7 of 9 in Crocodile Marico Catchments

●

Dam look like ?

WWhat does Hartbeespoorthat does Hartbeespoort

Consequences of HBS Dam Eutrophication

EExxcessivecessive algal blooms, algal blooms,

Hyacinth & Hyacinth & toxicitytoxicity

PProblem Statementroblem 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

AADRESSING GLOBAL DRESSING GLOBAL WARMING AND WARMING AND

DESERTIFICATION THROUGH DESERTIFICATION THROUGH IMPLEMENTING IWRMIMPLEMENTING IWRM

Harties metsi a me programme

www.dwaf.gov.za/harties

www.dwa.gov.za/harties

SaharaDessert

Middle East

Kalahari Dessert

South pole

Highest Solart Radiation

Is the biggest desert a natural occurrence?

Highest Solart Radiation

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 Industry Build on fossilized customs?

Environmental Impacts culminate in Desertification.

• 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 waves destroy 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

Lake Chad

1973197325 00025 000

1987198710 00010 000

200120011 3501 350sq kmsq km

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 ?

• Deserts = little to non vegetation > create deserts

• Forests = maximum vegetation > create forests

Desserts vs. Forests

Function of Vegetation

Photosynthesis

Absorb preserver heat

HEAT ENERGY

ORGANICS

FFunction of Vegetationunction of VegetationShadow – Cool soil reduce evaporation

Create micro-climate

Create micro climate that sustain environmental water balance & retention / sponge effect

Function of Vegetation & Organics

Increase water ingress & water

retention

Retain Moisture & Fertilise Soil

FFunctionunction of V of Vegetationegetation & & OOrganicsrganics

Block Heat Waves, Wind & Evaporation

FFunction of Vegetation & unction of Vegetation &

OrganicsOrganics

FFunction of Vegetation & unction of Vegetation &

OrganicsOrganics

Sustain bio-diversity Life conditions for extended food

web

FFunction of Vegetation & Organicsunction of Vegetation & OrganicsFFunction of Vegetation & Organicsunction 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?

EEffect of ffect of CCivilization &ivilization &

DDevelopmentsevelopments

EEffect of ffect of CCivilization &ivilization &

DDevelopmentsevelopments

VeldtVeldt Fires FiresVeldtVeldt Fires Fires

VeldtVeldt Fires FiresVeldtVeldt Fires Fires

AFRICA THE BURNING CONTINENT

• 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

Effect of Civilization/

Developments

IImpact - erosion & part of the gabions mpact - erosion & part of the gabions which have been washed away due to high which have been washed away due to high

flows – Clayville wetlandflows – 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

EEffect of Civilization/ ffect of Civilization/

DevelopmentsDevelopments

EEffect of Civilization/ ffect of Civilization/

DevelopmentsDevelopments

IImpact - Sand mining - Jukskei Rivermpact - Sand mining - Jukskei River

Challenge!Challenge!Challenge!Challenge!

Pilot Projects & Implementation Cases

Pilot Projects & Implementation Cases

• Water Use Efficiency + multiple water useWater Use Efficiency + multiple water use

• Waste minimization, recycling & reuseWaste minimization, recycling & reuse

• Enhance groundwater rechargeEnhance groundwater recharge

• Current implementation sites:Current implementation sites:– Impala platinum mineImpala platinum mine– Other Platinum mineOther Platinum mine– Harties, metsi a meHarties, metsi a me

IImplats: mplats: Super Compost from wastes: Super Compost from wastes: WoodchipsWoodchips and and Sewage Sewage Impala Impala

Platinum Platinum Case StudyCase Study

DWAF AuthorisationDWAF Authorisation

– From 2002 integrated water and waste From 2002 integrated water and waste management were require according to NEMA management were require according to NEMA & WSSD – waste minimisation and recycling& WSSD – waste minimisation and recycling

– Stipulate minimum rehabilitation in line with Stipulate minimum rehabilitation in line with improved / more efficient water use – improve improved / more efficient water use – improve soil/moisture content with organicssoil/moisture content with organics

EEnvironmental Challengesnvironmental Challenges• Sewage material potentially hazardousSewage material potentially hazardous

– Leaching of heavy metalsLeaching of heavy metals– High salt concentrationsHigh salt concentrations– Anaerobic conditions – smells, health hazards Anaerobic conditions – smells, health hazards

(patogens(patogens))

• Treatment & disposal costTreatment & disposal cost• Long term liability costsLong term liability costs

– Considered as nuisance and waste product – highly Considered as nuisance and waste product – highly regulatedregulated

Woodchip Case StudyWoodchip Case Study• Woodchip stockpiles and waste sites have Woodchip stockpiles and waste sites have

environmental impactsenvironmental impacts– Leaching of nitrogenous compoundsLeaching of nitrogenous compounds– Al toxicity if low pH experiencedAl toxicity if low pH experienced– No beneficial useNo beneficial use

• Great costs incurred to stockpile and transport Great costs incurred to stockpile and transport and dispose woodchipsand dispose woodchips– Legislation will not permit disposal of valuable organic Legislation will not permit disposal of valuable organic

“waste materials” “waste materials” (CMS)(CMS)

Waste Recycling ManagementWaste Recycling Management

Producing woodchip Compost

Producing woodchip Compost

Reusing of woodchip compost

Reusing of woodchip compost

The AnswerThe AnswerRehabilitation with organic material (compost)Rehabilitation with organic material (compost)

IIntegrated Environmental ntegrated Environmental ManagementManagement

Combine the organic waste materialsCombine the organic waste materials• Process:Process:

– Mix to a predetermined ratioMix to a predetermined ratio– Put it through a composting processPut it through a composting process

• WateringWatering• VentilationVentilation• EarthwormsEarthworms• StockpileStockpile

• Soil profile development• Moisture retention• Nutrient cycling• Organic carbon• Microbiological activation in tailings• Safe site & germination capacity• Seedling survival• Species consistency

Rehabilitation & Sustainability:Rehabilitation & Sustainability:Success criteriaSuccess criteria

• Success lies in soil amendmentSuccess lies in soil amendment– Acceleration of soil profile regenerationAcceleration of soil profile regeneration

• Proven solution lies in application of organic Proven solution lies in application of organic materialmaterial

Rehabilitation Rehabilitation SpecificationsSpecifications

• Better growth and more efficient water use, Better growth and more efficient water use, moisture retention > 50% moisture retention > 50%

• Better environmental option & cost savingBetter environmental option & cost saving• At 100 tons/haAt 100 tons/ha

– KNOKNO33 equivalent to minimum of 350kg/ha equivalent to minimum of 350kg/ha– Phosphate equivalent to minimum of 250kg/ha Phosphate equivalent to minimum of 250kg/ha

superphosphatesuperphosphate

• Biological soil activation Biological soil activation • Reduce water pollution – desalination with Reduce water pollution – desalination with

vegatationvegatation

Important ResultsImportant Results

Organic’s compost with vermiculture (garden, agricultural, mining & industrie)

excellent example of closing the loop with Elimination of waste

Example of integrated environmental management in action

Save astronomical costs•Impala: ± R1,4m/year•Waste sites up to 60%

New opportunities for researchPrimary focus on

questions surrounding stabilityDevelopment of new products

ConclusionConclusion ConclusionConclusion

ConclusionConclusionConclusionConclusionA high state of ecological stability

due to the high diversity of different vegetation types, eg. grasses, forbs

& tree species.

Annual and pioneer plant species contribute to the enrichment of the soil:

source of organic material & soil nutrients.

Addition of vermi-compost mixture to the soil on the mine tailings dams result in successful rehabilitation.

How to plant trees and re-vegetate dry areas?

• Find the right vegetation and it should also have an economical value

eg .Bio diesel, firewood, fruit etc.• Start a small area and plant closest to some source of

nutrients & water and extend from here. • Utilise Organic material (compost) to keep moisture on an

frequent basis. Watering can then be done with rainwater harvesting for the first two years after

which the trees roots have established themselves.• Support the plantation with Government and Private Grant

funding and ensure that enough and adequate skills and training development is done.

• These projects needs continuous extension and support, not only for the sake of the community that will benefit but also the

environment.

• Implement IWRM principals in Catchment to enhance Growth, Development and Work Creation.

• Determine, Optimise & Manage Physical and Biological conditions to increase diversity (1) within the dam and (2) in the catchment to ensure reduction in mono cultures like algal (blue-green) and biomass.

OOverall verall ObjectivesObjectives: HDRP: HDRP