Assessing the contribution and variations of spring discharges to river flows within the Nuwejaars Catchment, Cape Agulhas

Water resource management in South Africa has not stressed the importance of springs as a water resource and fails to integrate surface water and groundwater as one essential resource functioning interchangeably. The investigation of springs as a water resource is a way of understanding the integrated manner in which groundwater interacts with surface water. Therefore, the protection of springs is imperative especially when it comes to active springs which may be contributing significantly towards river flows during the dry season. Previous studies have proven that springs are a significant source of water for many terrestrial and aquatic ecosystems. In addition, literature also highlights that springs are critical in sustaining domestic and agricultural water supplies. There are various factors that may influence spring discharge rates such as varying land cover type, topography, lithology, aquifer characteristics, hydrology and climatic conditions. As such, quantifying and understanding the hydrological effects of these factors is crucial for effective water resource management as it reflects changes in water fluxes and storages within the hydrological cycle. In order to manage these changes, the study made use of various methods such as the application of Mannings’ equation, flow measuring structures, manual flow measurements, hydrochemistry and isotope hydrology to examine the effects of rainfall on spring discharge rates across four experimental spring sites within the Nuwejaars Catchment. Objective 1 of the study was to locate the occurrences of springs and examine factors accounting for their locations within the Nuwejaars Catchment. This identification process took into account variables such as the type of land cover, topography, lithology, structural geology, hydrogeology and hydrology at each experimental site. Objective 2 of the study was to investigate the temporal variations in the quality and quantity of spring discharges and discern factors accounting for these variations. This was done in order to distinguish changes in spring discharges between the dry and wet seasons. Objective 3 of the study was to investigate the response of spring discharges to rainfall events. This response was determined by monitoring rainfall and spring discharges on multiple timescales to unravel spring flow dynamics at various rainfall intensities.

Grantor dc:publisher.institution

University of the Western Cape

Year dc:date.issued

2025

Author dc:creator

• Ajam, Mogamat Yaaseen

• Spring discharge
• Spring flow
• Active spring
• Inactive spring
• Rainfall

Licence

• https://uwcscholar.uwc.ac.za/bitstreams/560fe887-96d5-444d-8c23-d8e44627430b/download