Hydrology

Formerly, the valley drained a natural catchment approximately 1.5km2 and had a small creek channel running through it approximately 1m wide. As the university expanded, the flow of the catchment reduced, so the creek bed was excavated and the flow was dammed to create a lake. By early 2000, the lake was in poor condition and the water quality was severely affected by siltation. This was mainly due to improper construction of the initial dam wall and further exacerbated by Typha infestation. Major restoration works were carried out. The lake was dredged, the Typha beds were removed and the dam wall was re-constructed. A channel was also formed in the bed to direct the inflow into the body of the lake. To further support the lake, storm water was channelled from nearby Halls of Residence carpark, the reserves paths and also from the roofs of the Environmental Education Centre and Environmental Research Laboratories. The channelled storm water runs through a wetland biofiltration system before entering the lake. Water quality is improved through the biofiltration system with the removal of unwanted heavy metals and reduced levels of phosphates and nitrates. An overflow channel was built to the east end of the lake to prevent water flowing over the dam wall and eroding it. The lake spans approximately 0.2 ha. Samples taken in 2020 revealed the presence of sensitive invertebrates such as mayfly nymph, caddisfly larva and water mites.

An industry standard water monitoring system and weather station is located on Farrington Pier. Data from remote loggers and associated infrastructure is frequently collected at set time intervals, recorded and stored on the Hobolink system.

Water parameters that are recorded include pH, electrical conductivity, temperature, dissolved oxygen and turbidity. Weather parameters that are recorded include temperature, rainfall, barometric pressure, wind speed/direction, relative humidity and lux.

Find out more about the Environmental monitoring data that is collected.

hydrology