This old-fashioned recipe calls for “potato water,” an ingredient that was likely pretty common back in the meat and potatoes days of the early and mid-20th century. However, unless you are making this after a large family gathering (Thanksgiving or Christmas for example), you might not be boiling potatoes for mashing or otherwise cooking them up. If that is your situation, you can grate a potato and prepare it in the microwave as described below.
The link below is where I started from; thanks King Arthur flour for the great basics your site provides!
https://www.kingarthurflour.com/recipes/sandwich-rye-bread-recipe
Dill Pickle Rye Bread
1 large (12 to 16 oz) potato, grated
approximately 2 c water
1 2/3 c rye flour
1 T caraway seeds
1 t dill weed
1 1/4 t salt
1 t sugar
1/4 c dill pickle juice
1/4 c. canola oil
1 pkg dry yeast (about 1 T)
2 1/2 to 3 c bread flour
1. Grate the potato, cover with water, and microwave for 4 to 5 minutes. Remove from microwave and place in a strainer, pressing down on the potato to extract as much liquid as possible. Measure out 1 1/2 cups potato water. If you have less than 1 1/2 cups, add water as needed to reach that amount.Set aside to cool to lukewarm.
2. Add all the remaining ingredients except the bread flour and beat about a minute, until very well blended. Set aside for 1 hour to allow the dough to raise and the rye flour to soften.
3. After an hour, beat in the bread flour gradually, stirring until a soft dough is formed. Turn out onto a floured surface and knead about 5 minutes, adding only as much flour as needed to keep from being too sticky. Rye flour will require a bit more kneading than you may be used to.
4. Cover lightly and let raise until double in bulk. Punch down and divide dough in two pieces. Shape each into a loaf shape and place in two 8 1/2″ X 4 1/2″ well-oiled loaf pans. Put in a warm place until doubled in bulk.
5. Bake in a pre-heated 325 degree oven about 25 to 30 minutes.
(May be placed in three smaller loaf pans, baking for about 20 to 25 minutes.)