Agricultural Potential Assessment

Transcription

1 Agricultural Potential Assessment Prepared for the Proposed Construction of a 200 Ml Water Storage Reservoir in Brakpan By Environet Consulting and Engineering For Sazi Environmental Consulting April

2 TABLE OF CONTENT SECTON 1: INTRODUCTION AND BACKGROUND INTRODUCTION BACKGROUND OF THE STUDY AREA PURPOSE OF THE STUDY STRUCTURE OF THE REPORT... 5 SECTION 2: PROJECT AREA Study area Locality area Land Use History... 6 SECTION 3: ENVIRONMENTAL CONSTRAINT Description of the physical environment and its constraints Soil Climate Vegetation... 8 SECTION 4: APPROACH AND METHODOLOGY Approach and Methodology Literature Review Fieldwork SECTION 5: AGRICULUTURAL POTENTIAL The Potential for Productive Agricultural Development Cultivation SECTION 6: CONCLUSION Conclusion

3 SECTON 1: INTRODUCTION AND BACKGROUND This section will describe the introduction and the background study as well as the purpose of the study and the structure of the report Introduction Environet Consulting and Engineering was appointed by Sazi Environmental Consulting to conduct an evaluation of the agricultural potential of the lands that is covering the proposed construction of a 200ML reservoir in Brakpan in the East Rand. The project is triggered by the fact that the Mapleton sub-systems, which supplies the Brakpan reservoir has shown indications that an extra storage of 200ML will be required by Due to the Mapleton Pump Station augmentation, it has become significantly inevitable to have sufficient reservoirs with adequate balancing storage at strategic areas, to store pumped potable water for 24 hours before dispensing. Thus this project fits within the broader objective of the Government of South Africa through the National Development Plan 2030 for access to potable water by the majority of the people of South Africa. The project will ensure future water supply as it will improve the infrastructure and portions of the network which are already functioning under pressure. The Brakpan Reservoir consists of three storage reservoirs which are interlinked and the Brakpan storage reservoir is directly supplied by the Mapleton Pump Station through the C8 and L6 pipelines and leaking L16 pipeline from Van Dyk Park junction. It is against this backdrop that the Rand Water is embarking on different survey and specialist investigations to establish if the vacant land inside the premises of the existing Brakpan reservoir would be sufficient to construct additional 200 Ml storage reservoir, coupled with the required inlet and outlet pipelines. The existing site is situated close to the medium sized plots clustered together that will be in danger with associated loss of life should the existing structures unexpectedly fail which might require the resettling of exiting occupants around the reservoir. It is also being proposed by Randwater for an alternative site(s) which is opposite the existing reservoir and vacant. The preferred and alternative site as provided by the client is presented in figure 1 below. 3

4 A site visit was done in preparation for an agricultural assessment of the proposed facility area. The environmental variables such as soil, climatic conditions of Brakpan, land use, vegetation types and sensitivity of the area are used as a basis for the agricultural potential assessment. Figure 1: Proposed Project Location Layout 4

5 1.2 Background of the Study Area The section designated for the proposed project is located within Ekurhuleni Metropolitan Municipality s ward 74. Brakpan is a gold and uranium mining town with about 346,735 inhabitants in the Gauteng province of South Africa. The Brakpan area covers an area that measures about km 2. The project site is located along 2 nd Road and Ergo Road in Brakpan. The preferred and alternative sites are opposite each other as indicated in figure 1 above. 1.3 Purpose of the Study The purpose of this survey is to determine and estimate the impact that proposed project would have on the environment, especially on agricultural aspect. In terms of the Conservation of Agricultural Resources Act (CARA) 48 of 83, the holder of the project right shall determine the impact that the proposed project would have on the environment. 1.4 Structure of the Report This report is subdivided in six sections, which are the introduction and background information, purpose of the study, structure of the report, study area and physical characteristics, approach and methodology, presentation and discussion of the results as well as conclusion. 5

6 SECTION 2: PROJECT AREA 2. Study area This section will entail the description of the locality area and land use history. 2.1 Locality area Rand Water proposes the construction of an additional 200 Ml storage reservoir, coupled with the required inlet and outlet pipelines inside the existing Brakpan Reservoir (preferred option) or at the opposite vacant land to the Brakpan Reservoir (alternative site). The study site has the approximate coordinate for the preferred site S26º , E28º , and the alternative site coordinate is S26º , E28º Land Use History The surrounding area for the designated additional 200 Ml storage reservoir, coupled with the required inlet and outlet pipelines indicates areas with land uses such as engineering services, open space, residential and small holdings as indicated in figure 2 below. The portion of land for the preferred option has a land use of engineering services and open space while the alternative site has a land use designated as open space. 6

7 Figure 2: Study area land use 7

8 SECTION 3: ENVIRONMENTAL CONSTRAINT 3 Description of the physical environment and its constraints This section will describe the soil, climate, vegetation and agricultural potential. 3.1 Soil The soils are generally shallow with underlying shale bedrock, usually no deeper than 1. The soils that weather out from these rocks are generally silty, sandy, gravely and with a relatively high clay content. The identified soil type on site is a clay loamy soil. This soil type can be difficult to work with and it can also be improved to be a very good growing medium. However, when the soil is very wet, it swells to retain water which then makes it difficult to work with. Over time, this poor drainage can also stunt plant growth. With the addition of organic matter, the soil can be a very good growing medium but with high cost of soil preparation. 3.2 Climate Brakpan normally receives about 579mm of rain per year, with most rainfall occurring during summer. The area receives the lowest rainfall (0mm) in July and the highest (108mm) in January. The monthly distribution of average daily maximum temperatures indicates that the average midday temperatures for Brakpan range from 16.8 C in June to 26.1 C in January. The region is the coldest during July when the mercury drops to 0.1 C on average during the night. 3.3 Vegetation The vegetation types that can be found on site is indicated in figure 3 below. The general vegetation type on site is the Soweto Highveld Grassland. The species that can be found on site include: Cynodon dactylon, Aristida congesta, Tristachya leucothrix, Typa capensis, Themeda triandra.. 8

9 Figure 3: Site vegetation types 9

10 SECTION 4: APPROACH AND METHODOLOGY 4. Approach and Methodology This section will describe the approach and methodology, as well as literature review and fieldwork applied during the investigation. The methodology used to assess the agricultural aspect was the phase approach method. The phases applied during the investigation are discussed below Literature Review An initial review of published literature was undertaken in order to gain details regarding the project and the study site. Furthermore, published literature was examined to know the historic of the site Fieldwork Fieldwork, initial site visits and formal sampling was done during March 2015 covering the spatial extent of the study area. Sample points were distributed randomly within the study site. Sampling of soil and vegetation types on the sites was conducted. General overview of the surrounding land use was conducted. 10

11 SECTION 5: AGRICULUTURAL POTENTIAL 5.1 The Potential for Productive Agricultural Development The cultivation of the lands designated for the project has proven not to have an agricultural potential as contemplated in the Gauteng Agricultural Potential Atlas (GAPA3) and the EMF framework of Ekurhuleni Municipality as indicated in figure 4 below. The surrounding area is dominated by already developed and disturbed areas. However, successful cultivation and production on the lands would require the application of vast quantities of organic material and fertilizer application before productivity can be achieved. So much remediation will be needed that will be prohibitively expensive. This process will be very long, as the structure of the topsoil must be modified to combat the effects of soil fertility and soil micro-organism loss. Furthermore, water management will have to be constructed to avoid the risk of soil erosion in the area. Therefore, for the land to be productive it would have to be sustainably irrigated and must produce sufficient excess organic material to plough back in order to maintain a suitable level of soil organic material. Sufficient water for the level of irrigation required is simply not available and the extraction of it would have a severe negative environmental impact on the general area, particularly the surrounding natural vegetation. 5.2 Cultivation In conclusion, the area designated for the proposed construction of an additional 200 Ml storage reservoir, coupled with the required inlet and outlet pipelines inside the existing Brakpan Reservoir (preferred option) or at the opposite vacant land to the Brakpan Reservoir (alternative site) is not economically productive. Therefore, taking into consideration the variables: soil, climate land use and agricultural production it makes the agricultural cultivation of the area impracticable. Therefore, it is recommended that the areas designated for the project is not appropriated for agricultural production and the disturbed areas could be considered available for some other type of land use. 11

12 Figure 4: Agricultural potential zones of the project area 12

13 SECTION 6: CONCLUSION 6. Conclusion Results of this study show that the proposed construction of an additional 200 Ml storage reservoir, coupled with the required inlet and outlet pipelines inside the existing Brakpan Reservoir (preferred option) or at the opposite vacant land to the Brakpan Reservoir (alternative site) will not have a negative impact on the land and they will be no need for any special environmental monitoring Programmes to comply with the Conservation of Agricultural Resources Act, 43 of CARA seeks to provide for the conservation of natural agricultural resources by maintaining the production of land, combating and preventing erosion and weakening or destruction of water resources, protection and combating weeds and invader plant species. A general environmental monitoring plan that will accompany the EIA report will be sufficient to deal with any negative impacts the project may have on the open space around the project site. In addition, the investigation in the area as shown in figure 4 above shows that the Brakpan area is not an agricultural potential area and hence the project will not be hindering any agricultural opportunity. 13