Bassenthwaite Lake is one of the largest lakes in the English Lake District. It is long and narrow, approximately long and wide, but is also extremely shallow, with a maximum depth of about .

It is the only body of water in the Lake District to use the word "lake" in its name, all the others being "waters" (for example, Derwent Water), "meres" (for example, Windermere) or "tarns" (for example, Dock Tarn). It is fed by, and drains into, the River Derwent. The lake lies at the foot of Skiddaw, near the town of Keswick. Some maps dating from the 18th century do in fact mark this lake with the name Bassenwater, and the use of name Broadwater for this lake is also attested.

The A66 dual carriageway runs roughly north/south along the western edge of the lake. With breathtaking views, the laybys are popular spots for photographers and bird watchers looking for osprey. The section running south towards Keswick was built on top of a former railway line leading to Penrith.

Origin

Like the other Lake District lakes, Bassenthwaite Lake lies in a glacially eroded valley, left after the last glaciation. Bassenthwaite Lake is linked to Derwent Water by the River Derwent, which crosses the alluvial plain between the two lakes. There has been speculation that Derwent Water and Bassenthwaite Lake were once one larger lake with the alluvial flats now separating them formed from partial infill of the original basin.

Biodiversity

The lake's catchment is the largest of any lake in the Lake District. This, along with a large percentage of cultivable land within this drainage area, makes Bassenthwaite Lake a fertile habitat.

The lake contains salmon, trout, pike, perch, minnow, dace, ruffe and eel, though the predominant species is roach, which is believed to have been introduced in the form of discarded live-baits by visiting pike anglers. Also present is the vendace, in one of only two locations it can found in England. Cormorants have been known to fish the lake and herons can also be seen; at the turn of the 19th century there was a report of 60 nests in a heronry in nearby Wythop Woods. In 2001, ospreys returned to nest by the lake, and have done so regularly since.

Threats

The lake currently faces problems which the Bassenthwaite Restoration Project is trying to address. These include erosion, pollution (especially phosphates which encourage algae formation) and a number of alien types of flora which are threatening to compromise local species.

Neolithic man

It has been reported that the wide gravel spreads between Derwent Water and Bassenthwaite Lake provided the best centre within Lakeland for Neolithic farming communities. Stone axes have been found in the area and particularly at Mossgarth, Portinscale.

Trivia

It is said that the lake is home to the Eachy.