There was little vegetation in the base of the valley and the prevailing winds used to take what little “blown” sand there was through this valley. The road to Middle Beach was then built and this then put an end to the wind bypass. The Bushman’s river was relatively fast flowing and hence little silting took place, and most of the sea sand from the Bushman’s side was deposited in the river. Hence there was no sand dune at the Bushman’s river end of the valley and in fact the river flowed along what is now Westbourne road and then at right angles out to sea. The explanation of the build-up of sand in the last 30 years is explained. The fact is that there was little sand in any volume blown down Dry Bones valley in the past, as there was very little sand build-up.
Growth of the Sand dune at Bushman’s River-Mouth
Understanding the Sand Dune and the options
The Solution recommended by the Consultants
Residents of Kenton have been adversely affected by the build-up of dunes and the problems associated with the accumulation of sand for many decades now. The development of a large dune system at the Westbourne Road Circle (WRC) in Kenton has been the subject of a number of studies by both CES and PRDW.
An intervention is becoming urgent as the estimated rate of sand movement has more than doubled, from approximately 0,7m per month in 2013, to 2m per month in 2020. The local Municipality has, unfortunately, been unable to address the problem, thus the residents formed the Kenton Sand Dune & Nature Association (KSDNA) to assist with finding a solution.
Long term management of the Sand
The effect of the stabilized dune will be to prevent sand from migrating over the dune towards Dry Bones Valley, instead it will continue to accumulate in front of the stabilized dune. The accumulated sand will be taken from the dune by a small loader (see picture) and then offloaded into a suitable vehicle for transport to Middle beach. This will happen, periodically, in quantities of approx. 75 cu per day.
The access path from Westbourne Road to the beach will be widened and wood chips laid for the small loader that will move this sand from the beach. The sand moved to Middle Beach will be readily dispersed by the tide and will represent a very small percentage of the sea sand that moves on this area daily.
Revegetation and rehabilitation plan
The most effective long-term method of dune stabilisation is through the planting of vegetation, generally self-maintaining, as coastal vegetation is adaptive to the harsh conditions to which it is exposed. It plays a very important role in binding the sand, thus creating a self-sustaining ecosystem, with minimal maintenance requirements, which is the ultimate goal. Once the bulk earthworks have been completed and the dune has been reformed and rebuilt, there are a number of measures which must be put in place in order to stabilise the dune for re-vegetation, such as establishing porous dune forming fences (preferably shade cloth wind nets) across the width of the dune, at 5m intervals in the upwind area (which will also prevent people trampling on newly established vegetation). Brushwood is also recommended in areas not fully exposed to the dominant westerly winds, and in areas of lesser wind exposure (hollows/flat areas), surface stability can be achieved by using mulch, which assists with retention of soil moisture and provides protection for seedlings. Wood chips can be used for surface stability in the proposed pathway.
Irrigation is also required to assist with the establishment of plants in the early stages of their growth, so they can evade moisture stress during their establishment period. It greatly increases the survival rate of planted seedlings. Typically, irrigation will be required during the hot and dry months and possibly for the first two years only. It has been confirmed that a borehole can be sunk on site and suitable water for irrigating plants is available.
The Contract to re-profile and re-habilitate the Sand Dune
The KSDNA will be entering into a contract to complete the Kenton Sand Dune Maintenance Management Plan which will be strictly in accordance with the DEDEAT approved and authorized Plan as covered above in the ‘DEDEAT Authorization’.
This contract covers the re-profiling of the Sand Dune and the creation of a new frontage for this sand dune that will prevent the new, accumulated sand from blowing inland.
The contract will cover the establishment of all the re-vegetation of this re-profiled sand dune to ensure its’ stablility, and will further develop the indigenous vegetation that exists in Dry Bones Valley and along the frontage of Westbourne Road.
The Funding of the Contract with the Municipality
The funding from KSDNA has covered all expenditure incurred during the last five years, and will continue to fund the costs for the total completion of the project. It is estimated that it will take a further three years for the vegetation to establish itself, which we hopefully predict for 2024.
A synopsis of the funding covers the total costs of all preliminary investigations undertaken in the last five years, the preparation of the Proposal, and all survey work during this period and in the finalization of the project Proposal. It covers the consultants’ work in finalizing project approval with DEDEAT and the overall supervision of the Contract to the required Environmental Standards.
The project itself, as described above, and the on-going management of the project, will have taken fully 8 years to bring to completion.
KSDNA will be delighted to have helped in re-establishing Kenton as one of the most beautiful places in the Eastern Cape, and for the community to enjoy this ‘gem’ in the years to come.