2. Keep watch

Overview

A Riverwatch water monitoring program will help us measure change over time, protect existing swimming spots, open new swimming sites and understand what makes water quality change over time.

Recommendation

Agree and progress the establishment of the Riverwatch monitoring program for the Parramatta River.

Timeframe

Now.

Lead Agency

Sydney Water.

Current Measure

Number of swim sites being monitored – existing, priority, future swim sites.

*TBA – To be advised. Not enough water quality data has been collected and assessed in conjunction with sanitary inspections to develop a suitability grade. Raw data for each of these sites is available on request.

**The combined outcome of the microbial water quality assessment along with a sanitary inspection, is a five-level classification Suitability Grading for Recreational Water Bodies, ranging from ‘very good’ to ‘very poor’.

This classification approach for our sites is consistent with the methodology Beachwatch uses. They define ‘Good’ as a ‘Location has generally good microbial water quality and water is considered suitable for swimming most of the time. Swimming should be avoided during and for up to one day following heavy rain at ocean beaches and up to three days at estuarine sites’. And ‘Poor’ as: ‘Location is susceptible to faecal pollution and microbial water quality is not always suitable for swimming. During dry weather conditions, ensure that the swimming location is free of signs of pollution, such as discoloured water, odour or debris in the water, and avoid swimming at all times during and for up to three days following rainfall’.

Sampling for enterococci is carried out on a routine basis every six days during the swim season and monthly in winter. The heavy rainfall and La Nina weather conditions that Sydney has experienced over the last two years has meant that water quality results have declined as a result of pollution washing into the Parramatta River. Our monitoring shows that sites are suitable for swimming three days after rainfall. This allows enough time for the river to naturally flush and the water quality to improve.

RiverWatch

RiverWatch^TM is Sydney Water’s recreational monitoring and reporting program. It works with councils and other organisations to establish new swim sites and monitor existing sites.

The RiverWatch microbial monitoring program follows the National Health and Medical Research Council’s Guidelines for managing risks in recreational water and the NSW Water Quality Objectives. It is aligned with similar recreational water quality monitoring programs such as Beachwatch to maintain a consistent approach across Sydney.

Water quality at any natural swim site can vary depending on weather, tides and other factors. When you check your local swim site, you’ll see today’s water quality readings. Sydney Water updates the predicted water quality at each swim site every day. Daily swim spot reports come from various reliable sources:

• Sydney Water RiverWatch predictive model that was developed in conjunction with the predictive modelling expertise of UNSW.
• NSW Beachwatch.

Sydney Water undertakes routine regular monitoring of the sites as well as targeted sampling, for example, after rainfall, to determine the individual site’s recovery time. They measure a number of parameters including enterococci, which can have a significant impact on swimming. These bacteria are excreted in faeces and are rarely present in unpolluted waters. Enterococci have shown a clear dose-response relationship to disease in humans.

Download the RiverWatch Water Quality Monitoring Program fact sheet.

Chemical Assessment Program

The Riverwatch chemical assessment program evaluates how chemical contaminants impact river sediment and water quality in the Parramatta River. Sydney Water has developed a framework in conjunction with EnRisk, The University of New South Wales, Sydney Water, NSW Health, NSW EPA, Department of Planning and Environment and swim site councils to assess human health risks from chemical contamination.

Sydney Water has applied enHealth’s Environmental Health Risk Assessment: Guidelines for assessing human health risks from environmental hazards to identify chemical contaminants of concern, understand toxicity and develop an exposure assessment for recreational water activities. This information will inform the sampling program and help to understand any potential risks that may arise from future recreation activities along the river.

Previous sediment and water quality monitoring within the river, and a review of historic land uses near proposed swimming sites, helps Sydney Water in identifying potential chemical contaminants of concern for recreational water users.

Download the RiverWatch Chemical Assessment Program fact sheet.

Conceptual Model

The Parramatta River Conceptual Model is a simplified representation of the real world that captures and integrates relevant scientific and other knowledge into a visual form to simplify communication for a wide audience. The conceptual model is divided into dry weather and wet weather which are the two dominant states that affect water quality in the Parramatta River. The pop-out images illustrate the different types of contaminants that affect water quality and swimmability in the Parramatta River.

Download the Parramatta River Conceptual Model – Dry Weather

Download the Parramatta River Conceptual Model – Wet Weather

RiverWatch predictive model

RiverWatch is Sydney Water’s environmental monitoring and reporting program that was established to support safe swimming in urban waterways. The RiverWatch predictive model issues daily pollution forecasts for our monitored sites, allowing the public to make informed decisions about when and where to swim.

Models are developed for individual sites by analysing the impact of key environmental factors on the levels of faecal indicator bacteria identified during routine sampling. Once the relationship between environmental changes and pollution is understood, we can determine the health risk from swimming at the site.

Download the RiverWatch Predictive Model fact sheet.

Status Update

Assessing recreational water quality in the Parramatta River is an important step in delivering the Parramatta River Masterplan. The Riverwatch microbial monitoring program assesses how microbial contaminants impact water quality in the Parramatta River. Along with the Riverwatch chemical assessment program, it helps inform decisions about proposed swimming sites along the river.

Progress Timeline

Useful Links

• RiverWatch™
• Sydney Water Urban Plunge™
• Beachwatch
• Water Quality at Lake Parramatta