Management of a shallow estuarine lake for recreation and as a fish nursery: Zandvlei, Cape Town, South Africa

The estuarine Zandvlei lake is an imporlant regional recreation resource in the SW Cape, South Africa. It is also an important nursery for migrantjuveniie marine fish species in the False Bay area. Extensive urbanisation in the catchment, and the regulation of lake water levels, have brought about changes to the water chemistry, hydrology and biota of the system. These perturbations have compromised the fishnursery role of the estuary and pose water quality-related health and aesthetic threats to the sustained recreational use of the lake system. Optimisation of the existing management practices should be directed towards enhancing water quality and the user-orientated roles of the lake. These include:effective stormwater and river management in the catchment to reduce bacteriological and nutrient loading;containing peak runoff flows;manipulation of the outlet channel to maximise seawater intrusion and allow access for migrant marine fish in early summer;control of the macrophyte standing stock to ensure that its vital role is unimpaired; andimproved education of both users and managers.