Use
the A1, rather than the M1 - going round Leicester can be tedious. Take the A606
towards Oakham, and after Empingham take left turn to Rutland Water north shore.
(Do not follow signs to Rutland Sailing Club.)
If you use the M1, go
to J21 Leicester, take ring road to A47 then Uppingham. A6993 to Oakham, then
signs to Empingham and Whitwell.
Anglian Water website.