Hilton Head PSD urges residents to reduce irrigation to protect island water supply

Hilton Head Public Service District is asking residents to take a closer look at their irrigation practices heading into winter, reminding customers that landscape watering remains one of the island’s largest and most avoidable uses of treated drinking water.

The PSD, which serves more than 19,000 customers across the north- and mid-island areas, said that 40 to 60 percent of annual tap-water demand on Hilton Head Island is tied to residential landscape irrigation.

Utility officials noted that many customer questions about high water bills can be traced to inefficient irrigation practices rather than indoor household use.
The district emphasized that the same water used for lawns and landscaping is the treated drinking water required for public health, safety and the island’s overall economy.

“With Hilton Head Island receiving more than 50 inches of rainfall a year on average, the need to supplement with irrigation is often quite limited,” the PSD noted in its guidance. The agency encouraged homeowners to use the winter season to evaluate the effectiveness of their systems and adjust watering schedules accordingly.

The district also highlighted online water-efficiency resources available at hhpsd.com and provided additional guidance from Clemson University’s Cooperative Extension Home & Garden Information Center. Clemson Extension offers detailed recommendations on winter irrigation, turfgrass care and landscape maintenance that vary depending on grass species and seasonal conditions.

According to Clemson Extension, warm-season grasses such as St. Augustinegrass, zoysiagrass, centipedegrass, bermudagrass and bahiagrass typically enter dormancy in winter, particularly in inland and Upstate regions. While the Lowcountry’s coastal climate is milder, turfgrass activity still slows significantly in winter months. Dormant grass is not dead—roots continue to take up water and nutrients, though at a reduced rate.

Clemson experts recommend applying roughly 1 inch of water only if a three-week dry period occurs without rainfall. Moist soil can help retain heat, reducing the risk of cold injury during temperature drops.

Overwatering in winter, however, provides no benefit and may damage turf if a freeze follows irrigation.

Cool-season grasses such as fescues and ryegrass remain active into the winter and may need occasional watering. Clemson recommends simple tests to determine whether cool-season turf requires irrigation, including checking for footprints that remain visible, observing leaf color or examining leaf texture.

Both the PSD and Clemson Extension caution homeowners against linking turf zones to irrigation zones for ornamentals, shrubs and flower beds. Many ornamental plants continue to require periodic watering during winter, while turf typically does not. Combining them can lead to wasteful watering or accidental turf damage.

The district also addressed common questions about winterizing irrigation equipment. Clemson Extension reports that most irrigation systems in South Carolina do not require full winterization because underground pipes are buried deep enough to avoid freezing. Above-ground pumps, however, should always be drained unless they are stored in a heated location. While draining system lines is not typically necessary, the practice is not harmful if residents choose it.

Overall, the PSD encourages residents to be mindful of water use throughout the year and to rely on rainfall as the primary water source for winter landscapes.

More information about water conservation is available at hhpsd.com/about-our-water/water-conservation. Clemson Extension resources can be found at hgic.clemson.edu.