CONSTRUCTION OF MTWALUME DAM, VULAMEHLO CROSS- BORDER WATER SCHEME, HARRY GWALA DISTRICT MUNICIPALITY, KWAZULU-NATAL Environmental Impact Assessment Report Authority Reference Number: DC43/0020/2014 June 2016 Draft Prepared for: Ugu District Municipality Title and Approval Page Construction of Mtwalume Dam, Vulamehlo Cross Border Water Scheme, Project Name: Harry Gwala District Municipality, KwaZulu-Natal Report Title: Environmental Impact Assessment Report Authority Reference: DC43/0020/2014 Report Status : Draft Applicant: Ugu District Municipality Prepared By: Nemai Consulting +27 11 781 1730 147 Bram Fischer Drive, +27 11 781 1730 FERNDALE, 2194 [email protected] PO Box 1673, SUNNINGHILL, www.nemai.co.za 2157 Report Reference: 10550-20160603-Draft EIA Report R-PRO-REP|20150514 Authorisation Name Signature Date Author: Kristy Robertson 20160602 Reviewed By: Donavan Henning 20160603 This Document is Confidential Intellectual Property of Nemai Consulting C.C. © copyright and all other rights reserved by Nemai Consulting C.C. This document may only be used for its intended purpose Proposed Mtwalume Dam EIA Report Draft Amendments Page Amendment Date: Nature of Amendment Number: 20160408 First Draft for Internal Review 00 20160512 First Draft for Client Review 01 20160603 Second Draft for Client Review 02 20160614 First Draft for Public and Authority Review 03 Proposed Mtwalume Dam EIA Report Draft Executive Summary PROJECT BACKGROUND AND MOTIVATION The Ugu District Municipality (DM) owns and operates the Vulamehlo Water Treatment Plant (WTP) which supplies potable water to areas within the Vulamehlo and Umzumbe Local Municipalities in Ugu District Municipality as well as to areas within the Ubuhlebezwe Local Municipality in Harry Gwala District Municipality. The WTP is located just off the Mtwalume River in the vicinity of the boundary between Harry Gwala (DM), formerly Sisonke District Municipality and Ugu DM. The existing WTP had an original design and operating capacity of 1.5 Mℓ/day and has since been upgraded to treat a total of 4.5 Mℓ/day. Operations and investigations indicate that the existing infrastructure is not adequate (based on coverage and capacity) to meet the demands of the project area. Thus, ZIYANDA Consulting cc (ZIYANDA) was appointed in May 2013 as the Engineers to undertake detailed design work and construction management for the augmentation of water supply to the project area through a proposed scheme, Vulamehlo Cross Border Water Scheme. The scope entails, inter alia, construction of Mtwalume Dam on the Mtwalume River, upgrading of Vulamehlo WTP, bulk infrastructure (reservoirs and pipelines) and reticulation and the extension of the infrastructure to cover the currently unserved areas including KwaMgayi and Hlokozi areas. For the raw water impoundment and storage infrastructure, ZIYANDA has collaborated with Bosch Stemele (Pty) Ltd to undertake the engineering planning and detailed design of the works for the proposed Mtwalume Dam, which is to provide adequate raw water for the proposed Vulamehlo Cross-Border Water Scheme. Nemai Consulting was appointed by ZIYANDA as the Environmental Assessment Practitioner (EAP) for the project. Only the proposed Mtwalume dam is covered in this EIA. A significant growth in the water requirements for the system has been predicted through various previous studies, and a substantial portion of that growth can be associated with the increase of the level of service for the rural population as well as the planned extension of the system to cover additional rural areas, which are not presently supplied with water from the scheme. Initial demand forecasts were based on a per capita water consumption of 60 ℓ/c/d. However, both the Ugu and Harry Gwala District Municipalities have indicated that future demand projections should be based on a per capita consumption of 75 ℓ/c/d. The ability of the Mtwalume River to sustain these demands, as well as the subsequent implications regarding the raw water storage infrastructure was investigated. The raw water supplying the WTP is abstracted from a weir on the Mtwalume River. Hydrological assessments of the Mtwalume River conducted by Umgeni Water (2001) and June 2016 - i - Proposed Mtwalume Dam EIA Report Draft Terratest Geotechnical, Environmental and Earth Science Consultants (2011) to determine the volume of “run-of-river” streamflow available at the existing Vulamehlo Weir, indicated that in order to meet the current and future domestic water demands of the surrounding community in addition to implementing the ecological water requirements, additional in-catchment storage will be required in the form of a dam on the Mtwalume River. PROJECT LOCATION The proposed Mtwalume Dam will be located on the Mtwalume River in a section of the River that falls within the Harry Gwala District Municipality. The dam is located approximately 32km west of Umzinto and approximately 45km west and inland of Scottburgh on the south coast of KwaZulu-Natal. The area is rural in nature with a number of residential / community areas on the periphery of the proposed dam sites that include schools and clinics as well as some intensive sugar cane farming and forestry. Access to the dam sites is possible via gravel roads that run off the R612 that links the coastal areas with the towns of Ixopo and Highflats. Locality Map PROJECT DESCRIPTION Two Dam Site options have been assessed: Dam Site 3 consists of the following: June 2016 - ii - Proposed Mtwalume Dam EIA Report Draft o Dam Wall: The centerline for the proposed dam wall for Dam Site 3 (30°19'26.16" S; 30°19' 25.52" E) is located approximately 1km upstream of the existing Vulamehlo Weir where the river flows through a relatively narrow valley section. The dam wall is proposed to be 40m in height. The valve chamber and intake tower as well as bridges for these structures will be constructed at the dam wall. o Dam Basin: The dam basin is approximately 260m wide upstream of the proposed centerline. The width remains relatively constant up to the bend in the river where it decreases in width to 230m some 650m upstream of the bend before reducing gradually to the head waters roughly 4300m upstream of the centerline. The total area to be inundated is approximately 117 ha. o Associated infrastructure: The following structures are to be constructed for temporary use during construction, except for structures where specified, and all structures occur within the proposed construction footprint for the associated infrastructure: . Potable Water Pipeline (will be permanent); . Concrete Access Road (will be permanent); . Water Storage Tank; . Mixing & Concrete Batching Plant for Storage of Concrete Materials; . Site Camp; and . Site Office. Dam Site 5 consists of the following: o Dam Wall: The centerline for the proposed dam wall for Dam Site 5 (30°19'00.16" S; 30°18'00.89" E) is located approximately 5.1km upstream of the existing Vulamehlo Weir where the river flows through a relatively narrow valley section. The dam wall is proposed to be 35m in height. The valve chamber and intake tower as well as bridges for these structures will be constructed at the dam wall. o Dam Basin: The total area to be inundated is approximately 114 ha. o Associated Infrastructure: The following structures are to be constructed for temporary use during construction, except for structures where specified, and all structures occur within the proposed construction footprint for the associated infrastructure: . Gravel Road (will be permanent); . Potable Water Pipeline (will be permanent); . Culvert River Crossing (will be permanent); . Concrete Access Road (will be permanent); . Water Storage Tank; . Mixing & Concrete Batching Plant for Storage of Concrete Materials; June 2016 - iii - Proposed Mtwalume Dam EIA Report Draft . Site Camp; and . Site Office. SCOPING AND EIA PROCESS The proposed Mtwalume Dam entails certain activities that require authorisation in terms of the National Environmental Management Act (NEMA) (Act No. 107 of 1998). The process for seeking authorisation is undertaken in accordance with the EIA Regulations (GN No. R. 543, R. 544, R. 545 and R. 546 of 18 June 2010), promulgated in terms of Chapter 5 of NEMA. Subsequently, the 2010 EIA Regulations were amended in 2014; however, the Mtwalume Dam Application is in line with the 2010 EIA Regulations. Based on the types of activities involved which include activities listed in GN No. R. 544 and R. 545 of 18 June 2010; the requisite environmental assessment for the project is a Scoping and EIA process. In terms of the Regulations, the lead decision-making authority for the environmental assessment is the KwaZulu-Natal Department of Economic Development, Tourism & Environmental Affairs as the project proponent is the Ugu District Municipality. Nemai Consulting was appointed by Ugu District Municipality as the independent EAP to undertake the Environmental Authorisation for the proposed construction of the Mtwalume Dam. Scoping and EIA Process June 2016 - iv - Proposed Mtwalume Dam EIA Report Draft ALTERNATIVES Two Dam Sites have been considered as alternatives for the Mtwalume Dam project. The proposed co-ordinates of the centre of the dam walls are as follows: Site 3 Site 5 30° 19'26.16" S; 30° 19' 25.52" E 30° 19'00.16" S; 30° 18'00.89" E PROFILE OF THE RECEIVING ENVIRONMENT The EIA Report provides a general description of the status quo of the receiving environment in the project area, and also provides local and site-specific discussions on those environmental features investigated by the respective specialists. This allows for an appreciation of sensitive environmental features and possible receptors of the effects of the proposed project. The study area includes the entire footprint of all the project components, which includes the construction domain and surrounding receiving environment. The receiving environment is assessed and discussed in terms of the following: 1. Climate 2. Geology 3. Geohydrology 4. Topography 5. Surface Water 6. Flora 7. Fauna 8. Land Capability 9.