Mapped below are the average scores for both ecology (in green) and swimming (blue), measured from the Waihou River at Okauia in 2016/17, compared with other monitored rivers in this district.

It is noted that in 2017/18, only swimming and ecology measurements from individual monitored sites were produced, rather than a comparison of this data between monitored sites as had been done in the past.

Earlier measurements show the water quality in the district's main rivers ranged from excellent/satisfactory to unsatisfactory. From 2000-2004 nearly 38% of the samples taken from rivers within the Hauraki catchment were excellent, while 41.3% were unsatisfactory.

In the Matamata-Piako district, water quality for swimming in all the rivers and streams has worsened. E-coli data from 2006–2010 and water clarity data from 2003–2007 have indicated that a greater number of ‘unsatisfactory’ periods of water quality for swimming have occurred.

Two complaints of contaminants entering waterways were lodged with Council in 2012/13, and both were passed onto the Waikato Regional Council for investigation. In 2013/14 and 2014/15 there were no complaints received regarding water quality. In 2015/16 one complaint was received about oil entering the stormwater system following a car accident. This was handled by the Regional Council. There were no complaints about water quality.