What we know
The post office that replaced Bassett's Mills in April 1872; postmasters Dr. S. S. Wallihan (1876) and James M. Wadsworth (1877); Husted's sawmill 'near Southwater' burned in December 1877; the office moved to Husted and took its name at the end of 1878. Place Names of Colorado also calls it 'Borsts', but the 1872 guide lists Borstville as a separate station.
Where it was
Center of Sec. 1, T12S R67W, from Place Names of Colorado ('RR Post Office on D&RG 1872-1878. Moved from Bassetts Mills. 4 mi S of Monument'), via the BLM PLSS survey grid; good to about half a mile. The News's 1872 guide to the line puts Southwater 'at the sixtieth mile-post', with 'a postoffice and extensive siding for the loading of ties and lumber'; Husted, a mile south, was 61 or 62 miles from Denver (1873, 1881).
Placed from a written description, such as a land section, a distance from a landmark or an old survey note.
Sources
Sources are named in the text above. Numbers such as S-0080 refer to our source list. Most newspaper quotations were read in the Colorado Historic Newspapers Collection. Long quotations from recent books are shortened here.