Striving for resilience in the face of climate change Three years and eight months have elapsed since the country suffered one of its worst flooding events, affecting a couple of districts mainly in east-south region and Praslin and La Digue, with La Digue the worst hit of the two. There were swift actions by government to address the flooding issues through the setting up of a National Drainage Task Force (DTF) to plan and implement projects on the three main islands to alleviate the flooding events being experienced by the community with each heavy rainfall. Government has received much support ranging from financial aid to technical expertise that rendered the tasks of the DTF Committee easier in its quest to produce a drainage master plan for the country and at the same time implement selected projects that were crucial for flood mitigation control in the affected areas. To date, more than fourteen major flood mitigation projects have been implemented and completed on the three main islands, costing government more than R24 million, not counting the emergency works that were carried out during and just after the tropical storm Felleng. These projects have boosted the rapid storm water evacuation in the low-lying areas at strategic locations based on the studies carried out by the experts, some of them voluntarily offered their services. Massive storm water outlets are up and running, bringing much relief to the local and business communities ensuring some level of protection for properties and livelihoods of local businesses and residents in these flood prone areas. Completed projects from 2013 to 2016 1. Victoria Car Hire Bridge near Children s Playground at Anse Aux Pins 2. Bridge near Reef Holiday Apartments Anse Aux Pins 3. Bridge at La Passe 4. Drainage network at Turtle Bay - Au Cap 5. Bridge at L Union Estate 6. Box culvert and connecting drain at La Passe near DA s office La Digue 7. Box culvert and connecting drain near Police Station La Digue 8. De-silting and rock armouring Lanmar Soupap Phase 1 9. De-silting and rock armouring Lanmar Soupap Phase 2 10. Flood mitigation works (excavation of drain and de-silting marsh channel at Mare Duranto Côte D Or Praslin 11. De-silting of marsh channel at St. Joseph area phase 1 and 2 Grand Anse Praslin 12. Flood mitigation works, (de-silting of river construction of bridges) near Nouvelle Decouverte marsh 13. Construction of drain at Côte D or 14. Construction of drainage network at Upper Anse Des Genets Pointe Larue ON-GOING PROJECTS A combination of flood mitigation and erosion control projects are on-going on the three main islands under the DTF projects component and also from the Energy & Climate Change Department in line with the National Drainage Master Plan produced by DTF and CCD dept. L Union landfill bridge
The 4m wide span bridge is near completion that will complement the de-silting of the Lanmar Soupap phase 2 and the construction of the major L Union Bridge at the coastal front. This will ensure a wider capacity for the discharge storm water flow from the back area of the marsh up to the La Digue reserve area. Box culvert near Fish Trap La Digue
Work has started on this project to add up the two box culverts constructed recently near the DA s office and the Police Station, again in line with the DTF Drainage Master Plan for La Digue. Timeline for the completion of the project has been set for November 2016. Flood mitigation project at Cap Samy and Marie-Jeanne Housing Estate 1 & 2 Massive excavation works are on-going from the Cap Samy marsh up the Marie- Jeanne Estate 2 and will be complemented with the construction of five box culverts at strategic locations under the road to reconnect the two sections of the marsh that has been cut off due to the heavy siltation and the decayed old dredger pipes that have been blocked and hampering the flow from the sections of the marsh. This project is being financed under the EBA SSC China at the cost of R2.8 million as part of the marsh restoration programme under the project. The project is 50% complete, as most of the de-silting works have been carried out. The outcome of the project is to improve water circulation within the marsh and increase its capacity to evacuate storm water flow during heavy rainfall. The duration of the project is five months. Green Estate Bridge Au Cap This project to construct a 6m wide bridge on the Green Estate Road is well underway. This will improve the flow from the section of the marsh found below the Home for the Elderly. An overflow channel will be excavated crossing the ex-hydroponics farm to be connected with the bigger channel at the Reef Golf Course and discharge into the new bridge at the Reef apartments. 55% of the works have been completed and now with the road diversion and coffer dam completed, works will now concentrate on the demolition and re-construction of the bridge, which will follow with the excavation of the connecting channel to the Reef Golf Course channel.
Flood mitigation works at Ex-Chetty flats Anse Aux Pins Works on the above-mentioned project has already started, comprising of de-silting/re-profiling of the marsh channel, rock armouring works, construction of bridges and retaining walls and sedimentation ponds from the Chetty flats area to near the Carefree guest house. Almost 1km of heavy works to improve the hydraulic capacity of the channel, stabilisation of the embankment and eliminating some bottleneck at some existing bridges along the channel. The residents have been informed of the project and negotiations have been concluded with the signing of the way leave to allow for the implementation of the project which will be impacting several properties. The project timeline is 6 months, with the scheduled completion time to be before end of December 2016. Flood mitigation works near Carefree guest house Anse Aux Pins The contract for the construction of the Carefree bridge and drain has been signed and work is expected start soon with the installation of the road diversion on the seaward side of the main road. The bridge will be similar to that of the two bridges at Victoria car hire and Reef apartments at Anse Aux Pins and Au Cap. This bridge will complement the widening and re-profiling of the Chetty flats channel, so as to improve its capacity to receive the flow from the Chetty flats channel. The timeline has been set for the duration of 6 months. Other DTF and CAMS projects The DTF and the Climate Adaptation and Management Section (CAMS) are continuing with the implementation of the flood mitigation projects on the three main islands, with priority given to the most critical ones based on the vulnerability of the community. A series of projects have been earmarked to start early next year on the three main islands, some of them to be financed under the GCCA+ mostly on La Digue which was severely hit during the tropical storm Felleng. Projects will comprise a series of outlets, box culverts, connecting drains and the implementation of the flood mitigation on Lanmar Soupap phases 3 and 4. Other flood mitigation works on Praslin will comprise de-silting of river and marsh channels, construction of bridges and stabilisation works on the river and marsh embankments in both districts on Praslin under capital projects for 2016. Apart from these heavy engineering projects, the ministry is continuing with its cleaning and maintenance programme for all rivers and marshes on the three main islands and the number of sites under this programme has been on a steady increase for the past five years, maximising the allocated budget under this programme. This is being complemented by few voluntary works that are carried out by some organisations and groups to improve the status of our rivers and marshes, thus enhancing the biodiversity in these areas.
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