@austinhuang sorry misspelled your name, see above
@austinhuag thank you but I'm trying to go from JOSM into Inkscape, not from Inkscape into JOSM
Thanks for your advice!
@Marcello you have a good point about the lake. It's really there because I like lakes rather than any geographically justified reason. I hadn't thought of a dam before though, I might work the lake into one of the rivers then!