A multi-staged management strategy for restoring tidal flushing

Tidal restoration/wetland rehabilitation projects are being undertallimitations, this paper presents a tidal restoration/floodgate manipulation strategy that was developed from a four-year field study undertaken in southeastern NSW and subsequently applied at multiple field sites. An eight stage methodology is proposed to incorporate water quality, hydraulics, groundwater/saline intrusion, hydrology, field monitoring and flood design criteria. The strategy begins with a quantification of perceived outcomes for the study. Using these goals, the potential improvement in water quality are calculated using ion association models and field sampling techniques. The third stage quantifies the spatial flooding extent using GIS spatial analysis methods. The risks associated with saline intrusion into the sub-soil matrix are detailed using gnidelines developed from calibrated numerical models and field data. The modified floodgate designs are also discussed. Finally, field-monitoring recommendations are given with specific emphasis on chemical speciation, data retrieval methods and quantification of mass flux levels. Tidal restoration should only be undertaken once every criterion has been addressed.