[1] In 1803, Evans was appointed acting Surveyor General of New South Wales whilst Charles Grimes was on leave in England.

[2] On 13 November 1813 Governor Lachlan Macquarie sent Evans across the Blue Mountains into the Wiradjuri nation of central-western New South Wales to confirm the findings of the exploration party of Blaxland, Lawson, and Wentworth.

A cairn on the North Logan Road, 13 kilometres from Cowra was unveiled in 1978 on private property to mark the site where Evans, accompanied by his exploring party comprising George Kane (alias Thos.

Appledore), James Butler, Patrick Byrne and John Tighe, sighted the Lachlan River and named the surrounding district, Oxley's Plains in 1815.

Oxley had to change his plans since he couldn't follow the Macquarie any further so he sent Evans on to scout ahead, with a small party, to attempt a north-easterly route across the plains and report back.

[7] This route brought his party back to the Castlereagh River at a more southerly point than his first crossing, in an area between the future villages of Armatree and Curban (15 miles apart).

John Oxley named the river that year in honour of the British Foreign Secretary, Lord Castlereagh, who had held the position since 1812.

It appears Lieutenant-Governor George Arthur found it difficult to positively prove the accusations with a general loose attitude to payments within that office.

(1) A standing bronze portrait on a large rusticated sandstone plinth of Evans is located in Kings Parade (Park) at Bathurst in the Central Tablelands region of inland New South Wales.

[10] (2) Near Evans' first crossing of the Castlereagh River in July 1818, south of the township of Coonamble, a memorial has been erected commemorating this event.

the plaque, set against a standing local stone, reads: "The Castlereagh River was discovered 2 km south of this point on 11 · 7 · 1818 / By Surveyor Evans, Second in Command of Oxley`s Exploring Expedition.