Here’s an excellent status report (PDF). Done in Oct 2006, so slightly dated, but it is a detailed document. Done by G. Baidya, Chief Engineer (CDM –R&D), NHPC
Comprises inputs on definitions and classifications of small hydro systems, details of small hydro projects in China, and the policy measures followed by the Chinese that have resulted in the excellent growth of small hydro in that country, details on statewise identified small hydro projects in India, barriers for small hydro development and potential financing schemes for development of small hydro in India and elsewhere.