TO the naked eye it looks good enough to drink – but what does it really contain?

That was the questions that more than 70 citizen scientists attempted to answer by joining a massive water testing project across Oxfordshire on Monday.

Schoolchildren, conservationists and un-trained volunteers took tiny samples of water from their local stream, pond, river or lake for the Oxfordshire Water Blitz.

They got their testing kits posted to them free from Wild Oxfordshire, which co-ordinated the event for a second year.

The aim is to build a water quality picture for Oxfordshire which will help scientists work out what bodies of water are polluted and how.

Even the group's program manager Hilary Phillips did her bit for the water blitz, testing a pond just outside the group's headquarters at Manor House in Little Wittenham.

Ably assisted by estate manager Sam Haynes, Ms Phillips said: "This event will help to identify and focus attention on freshwater bodies where we can have the greatest beneficial impact – protecting what is already good and identifying locations where cleaning up further is likely to be easiest and most effective."

They were also helped out by Luis Velasquez from Oxford environmental organisation EarthWatch which has offered to process the results of the Water Blitz for free.

The group will post a map of results on its website in due course.

This year's event was also timed to coincide with a regular sample of the river Thames by the Centre for Ecology and Hydrology at Wallingford.

Ms Phillips added: "This provides an opportunity for volunteers to take comparable water samples from across a range of freshwater habitats in the river basin including headwater tributaries, streams, brooks, canals, ponds and lakes."

The first Oxfordshire Water Blitz was held last year and data from it can be seen on

To date over 100 volunteers , have collected more than 1,000 samples from more than 300 sites.

The Oxfordshire citizen science survey was inspired by the "BioBlitz", defined by Bristol Natural History Consortium as "an intense period of biological surveying in an attempt to record all the living species within a designated area".

The concept was first coined in the United States in the 1990’s as a useful way to bring together members of public with experts to gain something of use to conservation.