10 REGULATORY REQUIREMENT 11 CONCLUSION

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2 ETHEKWINI MUNICIPALITY DROUGHT & INTERVENTIONS DROUGHT MITIGATION PROJECTS INDIRECT REUSE NORTH & SOUTH DIRECT REUSE - NORTH DESALINATION REMIX 8 INDUSTRIAL REUSE 9 IRRIGATION REUSE 10 REGULATORY REQUIREMENT 11 CONCLUSION 2

3 Supply 909 Ml/day of water from 9 Treatment Works km of water mains 263 Water Reservoirs water connections Treat 500 Ml/d of Waste Water 27 Waste Water Treatment Works km of sewer mains 3

4 (Reuse 2019, umwp1 2029) Reduced support to South Coast due to augmentation (Ngwadini Dam or Desalination) Water requirement projection scenario - July 2014 umwp1 (Smithfield Dam) Actual historic water use Re-use of Treated Effluent Spring Grove Dam Existing total integrated Mgeni WSS (including Growth in Darvill Return Flows) Volume (million m³/a)

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6 TONGAAT FURROW LOWER THUKELA RAISING OF DAM WALL LINK P2 TO GRANGE NORTHERN AQUEDUCT

7 30% 84% 45% 34% 85% 80% 512 Ml 7

8 Installation of flow restricting disks to domestic meters. Pressure reduction to minimum 150kpa at the critical point. Interdepartmental JOC and coordination meeting taking place to integrate internal processes around the drought. Engagement with the Chamber of Commerce. Water conservation notices placed on all utility bills. Non Compliance will be addressed individually. Extensive community awareness campaigns is being done to reduce consumption. Regular meetings with Ward Councillors, street pole adverts & radio communications. Consumers with above average consumption is being identified and addressed individually. Industries with high usage will be personally advised to reduce consumption and alternate supply method are being formulated. Some have volunteered to haul in water from other supply areas via tankers. Short term solution, to provide water through tanker service & Jojo tanks. Integrated Infrastructure to meet the new demand. The EWS sachet plant is being replaced with 2 new units.to service affected areas. Reuse of grey water for the Waste Water Treatment Plants is being investigated for industrial and commercial use and processes. Penalties and fines have been approved by Exco. R500 fine for domestic consumers and R for commercial and industrial consumers.

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10 SMITHSFIELD DAM Heading Text TONGAAT DESALINATION WATER RESOURCE PROJECTS REMIX DESALINATION LOWER MKHOMAZI ILLOVU DESALINATION

11 Water Treatment package plant utilising nanofiltration technology to treat borehole water exhibiting high fluoride, iron & manganese levels in the Ekhukanyeni Area or any other suitable site Indirect Re-Use at EWS Tongaat WWTWs (and in the future Umhloti WWTWs), by pumping back to Hazelmere Dam (10Ml/Day with increase to 140Ml/Day) Indirect Reuse at EWS Kingsburgh & Amanzimtoti WWTWs (30Ml/Day) Direct Reuse at EWS Kwamashu & Northern WWTWs (Total 100Ml/Day) 3Ml/Day Seawater Desalination Package Treatment Plant on the Ethekwini North Coast (Tongaat) (Possible upgrade to 12Ml/Day)- Feasibility 6.25Ml/Day Remix Plant at EWS Central WWTWs (Upgrade to 100Ml/Day) Groundwater mapping for entire Ethekwini Municipal area to assist in identifying streams and pockets of water that exist underground

12 Design Capacity = 10m³/hr Operating for 10hrs/day Potable water to supply local community

13 Pumping to Hazelmere dam part of the flow from Tongaat and Mdloti WWTW is limited Soluble reactive phosphorous Total dissolved solids Option 1: Combine flows & indirect reuse to Hazelmere 13

14 Option 2: Combine flows & build sea outfall 14

15 Tongaat WTW Design = 23 Ml/day Current = 14 Ml/day River Blend in furrow and abstracted at WTW Tongaat WWTW Design 12,5 Ml/day Current 7,8 Ml/day Feasibility study approved < R Option 3: Indirect reuse at Tongaat WTW 15

16 Nungwane Dam Amanzimtoti WWTW Design = 30Ml/day Current = 22Ml/day Kingsburgh WWTW Design = 7.8Ml/day Current = 4Ml/day Option 1: Amanzimtoti WWTW to Kingsburgh WWTW to Nungwane Dam 16

17 Amanzimtoti WWTW Toti WTW Design = 25 Ml/day Current = 7 Ml/day Kingsburgh WWTW Option 2: Toti WWTW to Kingsburgh WWTW to Toti WTW 17

18 Option A: Pump from 2 WWTW to Nungwane Option B: Pump from 2 WWTW to Toti WTW Volume = 9 Ml/day (1 in 100yr yield) Blend ratio 50: 50 Cost Reduced 18

19 Potable water reclamation from KwaMashu is discharged into the existing trunk main of the NA in the vicinity of Duffs Road. KwaMashu WWTW Design = 65 Ml/day Current = 52 Ml/day Potable water reclamation from Northern is discharged to the NA at Newlands east. Northern WWTW Design = 70 Ml/day Current = 59 Ml/day KwaMashu WWTW & Northern WWTW to existing Northern Aqueduct (NA) 19

20 Water re-use projects are complex and sophisticated, require high level of competence and skill. Capable implementation agency will require: Technical expertise Planning ability Project management capability Financial strength Trusted water services delivery Accepted by community and customers Compliance of existing WWTWs to achieve strict discharge standards is critical to the future success of water re-use. Strict enforcement of discharge standards; Addressing the management and performance failures of wastewater treatment plans. Water re-use has good potential to solve local water shortage problems Water re-use gives best quantitative benefit in coastal applications (uses water that would have discharged into the sea) 20

21 POSSIBLE LOCATIONS Possible Location/s of Tongaat/La Mercy Desal Plant 21

22 Existing Genazzano WWTW site with proposed 3 to 12 Ml/day plant 22

23 PROPOSED RISING MAIN & P/STATION PROPOSED 3 TO 12ML/DAY PLANT PROPOSED EXTRACTION/ P/STATION & RISING MAIN Existing Genazzano WWTW site with proposed 3 to 12 Ml/day plant 23

24 RESERVOIR CURRENT DEMAND FUTURE DEMANDS TOTAL DEMAND (ML/DAY) (ML/DAY) (ML/DAY) LA MERCY AIRPORT (LMA) WESTBROOK DESAINAGAR LA MERCY Gennazano WWTW site land needs to be secured. This WWTW is planned to be decommissioned but there are some studies underway by Iliso Consulting on behalf of THD to utilise/expand the works/site for future La Mercy Development. Detailed feasibility still to be commissioned for proposed containerised desalination plant and associated extraction wells & pumps at this location. Supply to LMA reservoir to be initiated potential delay of rising main stream crossing. Funding availability for desalination system and supply to LMA reservoir to be confirmed Supply to LMA reservoir dependent on transfer of LMA reservoir to EWS. UW currently obtaining board approval for this. Desalination 24

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26 In response to the demand EWS believes that a remix water system could support the deficit in supply, by installing a Demonstration Plant providing approximately 6.25 Ml/day with a possible ultimate scenario of 50 Ml/day for the Inner City and a further 50 Ml/day for the South of Durban. This in alignment to the growth expected and thus water demand increase. Joint team effort between ethekwini and Japanese government Proposed full scale100 ML/day plant 50% seawater + 50% sewage Electricity consumption down by 40 50% 26

27 DESIGN = 130 Ml/day INFLOW = 70 Ml/day COD AVE = 495 PH = 7.2 OUTFALL LENGTH = 3160m 27

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29 Aim is to treat 47.5 Ml/d of municipal wastewater to a near potable standard for direct reuse in industrial processes. 29

30 Alternative to augmentation of the city s Southern Wastewater Treatment Works marine outfall. Mondi Paper expressed the desire to increase it s off take of reclaimed water 30

31 Sustainable Development of Water Resources At capacity the plant reduces the city s water consumption by 5% Extends the life of the city s water catchment resources. Unused water can be directed to unserviced communities. Pollution Load Reduction and Waste Minimisation Reduction in the sea outfall pollution load by 24% The process operates at 97.9% water utilisation efficiency 31

32 SAPPI Water reuse for industrial purposes Discharged to the estuarine Open up economic and residential development Regionalization of treatment works UMKOMAAS WWTW 32

33 Cato Ridge wwtw consists of a bar screen at the head of works and 5 oxidation ponds for treatment Treats ± 300kl/day of domestic wastewater Treated effluent is pumped to neighboring golf course, were it will be used to water the golf course Excess effluent is discharged into nearby watercourse 33

34 DWS study Mvoti to Umzimkulu Consortium of consultants (R4A, CSIR, Golder Assts) Outcome water resource class Class define required level of ecological protection Regulate the quality and quantity of treated effluent that can be disposed to estuary 16 estuaries in ethekwini Durban Bay ( harbour) : umngeni are both excluded from this study Estuaries Included are : North : Ohlanga ; umdloti and uthongati South : Mbokodweni ; Little amanzimtoti ; umkomazi plus Isipingo lagoon Multi-criteria Analysis 34

35 PES REC TEC D C D Mdloti Umhlanga umngeni Tongati Durban Bay Sipingo Mbokodweni uthongati Max discharge to estuary = 20 Ml/day REC can only be achieved if no wastewater is discharged into the estuary Some sensitivity to level of treatment Ultimate capacity required = 140 Ml/day umkhomazi Little Amanz F E D C B A Mdloti Do NOT improve if wastewater removed as catchment quality is very poor. More closed = poor O2. Relative insensitive to level of treatment. Max discharge to estuary = 50 ML/day Ultimate capacity = 125 Ml/day 35

36 Mdloti Umhlanga umngeni Tongati Durban Bay Sipingo Mbokodweni Little Amanz umngeni EWR must be implemented as well as other recommended interventions Mbokodweni & Little Amanzimtoti Cost significant to improve and low importance. Further wastewater can be accommodated Estuaries must not become health hazard umkhomazi F E D C B A umkhomazi No further wastewater into estuary. The proposed Smithfield dam with appropriate operating rule will comply to the TEC 36

37 CURRENT DROUGHT INCREASING DEMAND NEED TO MITIGATE & STABILISE THE SYSTEM REUSE IS IMPORTANT TO IMPROVE WATER RESOURCES SUBSURFACE WATER IS BEING INVESTIGATED FOR POTABLE CONSUMPTION 37

38 Planning Engineer: Hope Joseph Contact: or