SDSU Extension Extra 6036, "Dealing with Drought Stress in Home Lawns," is available online at this link: http://agbiopubs.sdstate.edu/articles/ExEx6036.pdf. Or ask at your county Extension office.
Associate professor of turfgrass science Leo Schleicher and SDSU Research/Extension Associate for Turfgrass Science Shane Andersen wrote the publication. Andersen notes that cool-season turfgrasses in South Dakota typically suffer from summer stress during July and August, but many lawns in the state experience stress earlier than normal during drought.
Several options are available that will reduce watering costs and conserve water resources.
You can conserve water by temporarily withholding the water from the lawn and inducing summer dormancy. The objective is to supply just enough water to keep the turf alive until conditions improve. Applying 0.25 to 0.5 inches of water once every two to four weeks during summer is recommended.
That will keep the turf dormant but provide sufficient moisture to keep the crown and underground parts of the plant alive.
You can use indicator-based irrigation to maintain a green, actively growing turf. If you use this option, you will schedule watering by watching for visual signs that indicate the plants are becoming water-needy. Delaying irrigation until the turf exhibits symptoms of slight moisture stress can conserve water and still meet the water requirements of the turf.
Typical symptoms of moisture stress in Kentucky bluegrass include a change in color from green to a dark bluish-gray, folding and possibly twisting of leaves, and "footprinting." Footprinting indicates internal moisture deficit and loss of turgor pressure.
Irrigate to a depth of 6 to 8 inches to reach turfgrass root depth – shallower watering benefits weeds.
You can replace a cool-season turfgrass lawn with a drought-tolerant, reduced-input turfgrass species. Turf-type buffalograss requires less water, fertilizer, mowing, and pest control than typical cool-season turfgrasses. A single irrigation applied once a month is usually adequate to keep buffalograss green and vigorously growing from May into September.