Bernard Völlmy is a Swiss painter, now based in France, who works primarily in watercolor, but also in monochromatic and color watercolors combined with graphite.
His watercolor themes often include subjects with water — creeks and streams, small runs or even reflective puddles. These are approached with an eye to texture and interesting value contrasts.
Völlmy’s website is in French, but is relatively easily navigable by non-French speakers. The link I’ve posted takes you directly to his watercolor on paper gallery. You can find other galleries of images under the “Bernard Völlmy” menu tab. Among them is a section for his sketchbooks.