Constituent Council(s):Ryde City Council

Constituent stream(s):Shrimptons Creek

Rainfall Station(s):R12

Sewerage Overflows: 25

Stormwater outlets: 51

Water Quality sampling points: WQ038, WQ066

Pollution Control Device Numbers: none

Overview:

Landuse:

Period of sampling records: August 1989 - April 1998 % wet days: 57

Number of sampling occasions (N):7

Compliance of key indicators to ANZECC guidelines

Summary: The water quality in this sub-catchment is poor. Ammonia and faecal coliform levels indicate considerable pollution from sewage, and eutrophic conditions are suggested from the nutrient loadings, low DO levels and high chlorophyll - A readings.

Issues: This is a large urbanised sub-catchment with a large area of residential land. There are a large number of sewerage overflows for this sub-catchment and they are most likely overflowing in wet weather. It is also likely that dry weather overflows and exfiltration re occurring due to under capacity. Flooding is also an issue in this catchment and this may contribute to overflow problems.

Knowledge Gaps: Stormwater and sewerage information for this catchment are adequate, however, there are only two water quality sampling points for this catchment and they are situated near the mouth of the creek (LCR end). Further sampling may be required upstream to determine the inputs higher up in the sub-catchment.

Recommendations: Degradation of the sewerage system should be watched. Note that Ryde City council is currently auditing their sewerage system and is relining pipes in some cases.