Answer: Rugosas as a group are noted for their hardiness and ability to withstand severe neglect. In fact, the only pruning they require is to remove dead wood and to perhpas thin a bit by removing the oldest canes to allow air circulation through the shrub. Pruning to control size over time is nearly impossible because an established bush will grow back to full size quickly since it has such a strong root system. If there is a branch in the way, simply remove it. If the plants require severe size control, you might consider rerouting the path or transplanting them -- best done in fall or very early spring.
With regard to watering, they should be able to get along without supplemental watering (as they apparently have been so far) and yet in case of prolonged and extremely dry weather if they should show signs of stress you might wish to water them. If you do, be sure to water deeply less often rather than provide a light sprinkling daily. (Their roots are very deep.) You might also apply a few inches of organic mulch around the base to conserve moisture and keep down weeds.
Specialists in "old" roses or heirloom roses often include rugosas in their selections. You might try Heirloom Old Garden Roses, 24062 NE Riverside Dr., St. Paul, OR 97137 or perhaps Carroll Gardens, 444 East Main Street (PO Box 310) Westminster MD 21157 (800-638-6334) to begin gathering information about them.
Enjoy your roses!
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