River Lostock

Slack Brook drains an area around Brindle, having its source close to Thorpe Green just outside the village, whereas Whave's Brook rises near Brimmicroft and runs southwards, almost parallel to the Leeds and Liverpool Canal by Ollerton Fold.

[1] The name could also be a Brittonic hydronym,[1] derived from lost, chiefly (perhaps metaphorically) meaning "a tail" (Welsh llost).

[1] A derivative of the aforementioned lost, *lostǭg, perhaps meaning "a beaver" (though note Cornish lostek, "fox") could also underlie the name.

There are several components that are used to determine this, including biological status, which looks at the quantity and varieties of invertebrates, angiosperms and fish.

Reasons for the quality being less than good include sewage discharge, physical modification of the channel and poor nutrient management of agricultural land.