[1] The first known description in circa 1604 gives the name as 'Blaa-loche' and states that quhen the firmament is moft ferene and cleir then its is palide and dead coloured contrair to all wther vn-corrupt and fueit vatters.

The Bungle Burn outflow runs on down country, past the old mill site, Mossend and Tandlehill Farms, before making a confluence with the Lugton Water near the Bungleburn Bridge outside Burnhouse.

The loch is recorded in 1604-1608 as being well known to many weavers in the neighbourhood due to the abundance of reeds that grew there and the fact that they were used for making pirns.

[8] The solid geology is macroporphyritic basalt with carboniferous limestone at the Middleton Quarry site and these are both overlain by low river terrace and lake alluvium.

The surveyors record that "The loch is surrounded to a great extent by bed of reed canary grass with a dense zone of the sedge Carex aquatilis.

There is a good floristic structure at the site and it is also of real importance due to the presence of the very rare Cowbane (Cicuta virosa).

Rare species are Carex aquatilis, brown sedge (Carex disticha), cowbane (Cicuta virosa), white water lily (Nymphaea alba), ivy-leaved water crowfoot (Ranunculus hederaceus), and bay willow (salix pentandra).