The ‘Karepalli-Kothagudium’ was a branch railway feeding from the collieries in the Singareni coalfields near Kothagudiam (see Spelling Note) to Karepalli where there was a junction with the NGSR between Manuguru and Dornakal. The length of the line was 24½ miles(39km) with an intermediary station at Tadkalpudi, which was request only. Although opened to passenger traffic its primary use was to access the coal fields that had been opened at Chatakonda .
It was a broad-gauge ([[Rail_gauge#Broad_Gauge|BG]) line to give connection to the NGSR system at Karepalli. The branch was inspected on the 20th of February 1926 and opened on the 1st of April. It only crossed one river using a girder bridge. There was some confusion as to policing the new line as although built and operated by the NGSR it connected to British India Railways and therefore was expected to fall under British India Jurisdiction so that the continuity of standards and security could be met. This had been agreed in 1923  by the ‘Chamber of Princess’ .
There was also a proposal that it might be continued to Bhadrachalam, a place of pilgrimage on the British side of the Godaveri River . This railway extension was not constructed, and the 25 mile(40km) link to Bhadrachalam  is nowadays provided by a bus service from the station at Kothagudiam, referred to as Bhadrachalam Road .
Spelling Note :
- 'Kothagudium' is the town name in use up to the 1950’s. Kothagudem is the modern name. Kothagudam is used in error in some documents.
- 'Karepalli' is the only railway junction in Khammam district in Telangana, where the railway track from Singareni collieries meets Manuguru-Dornakal railway line 
- None of these spellings occur in "The Imperial Gazetteer".
- Mss Eur F196/44; “Agent's inspection report on the proposed line from Karepalli to Kothagudam; with photographs.”; 1921
- Brtitish Library ‘India Office Records’ “R/2/71/90 Policy of the Government of India in regard to the construction and maintenance of Railways in Indian States. Jurisdiction over the Karepalli-Kothagudium Railway”
- Wikipedia “Chamber of Princes” ; Retrieved 14 Oct 2017
- Wikipedia “Bhadrachalam”; Retrieved 14 Oct 2017
- Wikipedia “Bhadrachalam Road Railway Station”; Retrieved 14 Oct 2017
- Wikipedia “Karepalli"; Retrieved 10 Oct 2017
- “British Library Archives and Manuscripts Catalogue” - Search; Retrieved 14 Oct 2017