HA! I've got the same problem. The water where I live has 250 ppm dissolved solids, and ph 8. I've never had good luck with soaps; creams lather much better for me.
The work-around I've come up with is to add aprox. 5 to 10 mL regular drug-store brand glycerine to my lather bowl before lathering. Too much can kill your lather, but a little helps to improve it's glide.