Four western Wake County towns and Johnston County will join other Triangle communities by banning the use of lawn sprinklers and soaker hoses to conserve drinking water.

In response to the state's deepening drought, officials in Cary, Apex, Holly Springs and Johnston County all announced similar mandatory restrictions Wednesday. Morrisville, which gets its water from Cary, also will be affected.

Watering outdoor plants with a hand-held hose or a bucket will still be allowed in the Wake communities. Those using reclaimed wastewater to water their lawns will not be affected.

Apex's mandatory watering ban will take effect Friday.

The bans in Cary, Morrisville, Holly Springs and Johnston County will take effect Nov. 1.

For Johnston County, it amounts to a second tightening. Starting Monday, county water customers will be allowed to water their lawns only one day a week -- odd-number addresses on Tuesdays, even numbers on Wednesdays -- down from three. Then the outright ban kicks in.

"After mulling it over a couple of days and seeing what Cary and Raleigh were doing, we decided we ought to do it, too," Johnston County Manager Rick Hester said of the stricter restrictions.

The Wake towns share a water-treatment plant that draws its supply from Jordan Lake, which is now about 6 feet below full.

The towns have an estimated 205 days of water remaining in the lake -- more than double the supply left for Raleigh and the Wake towns that depend on Falls Lake for drinking water.

Cary officials said Wednesday that they have been closely watching water consumption for months but were prompted to act in part by Gov. Mike Easley's call this week for greater conservation. Easley asked on Monday that people stop outdoor watering, but the governor left mandatory restrictions up to the state's individual public water systems.

"Landscape irrigation is a significant water use, and targeting irrigation is the best way Cary can make a difference," said Bill Coleman, Cary's town manager. "Of course, we encourage everyone to do as much as they can."

The water supply situation in Cary and Apex is not as dire as in some other Triangle communities because of how the U.S. Army Corps of Engineers and N.C. Division of Water Resources allocates the available supply from reservoirs.

The water in Falls Lake, for example, is allocated for use both as a source of drinking water and to supply the downstream flow of the Neuse River. For Falls, 100 percent of the water allocated for drinking water is apportioned to the city of Raleigh.

In Jordan Lake, however, only about half the water capacity designated for drinking water use has been allocated -- benefiting Cary, Apex, Morrisville, Research Triangle Park, Chatham County and Durham.

The remaining half of Jordan's drinking water supply has not yet been allocated by the state -- meaning far less of the available pool is being used when compared to the rate of consumption in Falls Lake.

The ban on outdoor irrigation for water customers in Cary and Morrisville will run at least through Dec. 31. The town has also stopped issuing three-week exemptions from its watering rules to people establishing new lawns or reseeding.

Apex has also stopped issuing new watering permits. All permits already issued will be void in a maximum of 30 days, even if the date listed on the permit indicates a later expiration.

Car washing is still allowed, though with some restrictions depending on the town.

Officials in Cary and Apex said further decreases in the estimated water supply will result in additional and stricter conservation measures if the drought persists. They hope the new restrictions, once enacted, will save up to 5 million gallons of water a day and stretch the remaining supply to last longer.

Cary and Morrisville residents who violate the rules will get one warning. A second violation carries a $500 fine, and each additional violation carries a fine of $1,000. Either town could cut off water service for repeat offenders.

Apex and Holly Springs will also provide a single warning before fining violators up to $1,000.

"We want to get people to conserve as much as possible," said Bruce Radford, the town manager of Apex. "We want to ensure the drinking, bathing water supply we have exists as long as we can have it."

(Staff Writer Peggy Lim contributed to this report.)