We are organizing treks to Kagbhusandi Tal during end August/early September period.
Details of the lake can be found here: http://www.garhwaltourism.com/lakes/kagbhusandi_tal.asp
It is a medium to tough trek spanning 12 days Delhi to Delhi with an optionally included visit to vasudhara waterfalls involving one extra day of trek to and from Badrinath.