My guess is that it refers more to the river Ganga than it does to Kubla Khan.  I would venture that if it were the poem by Coleridge, the focus would be on the Pleasure Dome - not the River.  Location would also be wrong here for the poem.  Also, trying to squint, to see the costumes of the people - they seem Hindu to me.  Can't be sure, because the boat seems more Far Eastern.  Although, after checking some present day photos, the boat would not be far off.  However,  Ganga is a goddess and the river has been sacred for thousands and thousands and thousands of years.  Also viewed some aerial maps.  So, the Sacred River Ganga is my best guess.  But that's all it is.  How many points do I get if I'm right?  ;)

I get two points:
http://www.victorianweb.org/painting/goodwin/index.html

And from Peter Nahum At The Leicester Galleries:
http://www.leicestergalleries.com/art-and-antiques/detail/15020

In another thread, you wanted the name of a book on this artist.
Taking the lead from The Victorian Web's bibliography - here it is:
Albert Goodwin
Different prices, but not cheap any way you look at it, undoubtedly due to the year it was published: 1977.  C.