MakeoverMonday: Recreational water quality - bacteria trends by region

MakeoverMonday
Python
Data Viz
Regional trends in enterococci (CFU / 100 ml) at NSW swim sites from Beachwatch monitoring, inspired by the 2025 Makeover Monday Thames / Fulham Reach brief
Author

chokotto

Published

May 4, 2026

Overview

Makeover Monday 2025 week 10 centered Thames river monitoring with Fulham Reach Boat Club. The underlying tables live on data.world and are awkward to fetch in fully automated CI without credentials, so this makeover uses the open NSW Beachwatch extract published with TidyTuesday 2025-05-20: enterococci readings by swim site, date, and region, plus daily weather.

  • Angle: compare how median annual bacteria counts evolved across Greater Sydney regions (coastal harbours vs inner catchments).
  • Why it still fits MM: same decision lens as the original brief - is water quality stable, improving, or spiky for recreational users?

Original Visualization

Source: Makeover Monday and the data.world workspace for the Thames / Fulham Reach materials.

Dataset

My Makeover

Regional medians: harbours vs catchments

Key takeaways

  • Sydney Harbour and Northern Sydney sit at the top of the regional median ladder for much of the record - busy tidal flushing and urban runoff both show up in monitoring.
  • Western Sydney has fewer samples but often tracks lower medians - different site mix and distance from open ocean.
  • Useful hygiene metrics for swimmers are relative spikes, not just long-run averages - the distribution within each year is far wider than these medians imply.

This post is part of the Makeover Monday community. Monitoring data: TidyTuesday 2025-05-20.

CautionDisclaimer

This analysis is for educational and practice purposes only. Data visualizations and interpretations are based on the provided dataset and may not represent complete or current information.