Langley will unveil an update to its 2012 comprehensive water system plan and a set of proposed water rate hikes tomorrow in a special open house.

The meeting begins at 3 p.m. Thursday, April 19, and will be held at City Hall, 112 Second St., Langley.

Challis Stringer, director of Public Works, said the open house will focus on the water system comprehensive plan update, a document which includes capital projects over the next six years, and proposed annual rate increases until 2017.

While several rate schedules are under consideration, Stringer said the city is recommending one that officials believe will be beneficial to the majority of customers but also encourage conservation.

It proposes that residential customers who use less than 10,000 gallons in a two-month period, accounting for about 93 percent of Langley households, pay a base fee of $39.59 each month. As the city uses a two-month billing cycle, their bill would read $79.18.

Additional usage would then cost more depending on the amount used. For example, for every 100 gallons used after the 10,000 gallon benchmark, they would pay a 50-cent fee per 100 gallons up to 30,000. Any water used after that would cost $1.25 per 100 gallons.

“What we’re trying to do is target the higher users,” Stringer said.

Most residential customers would actually end up paying a little less, she said. Under the current schedule, the base rate is $25.46 with a 43-cent charge per 100 gallons. As most households use about 117 gallons per day, that works out to an average monthly bill of a little more than $40.

“For most users, their rate will go down by about $1,” she said.

The proposed schedule includes an annual hike of 5.6 percent, which tops out for residential customers using less than 10,000 gallons in a billing cycle at $52.98 per month in 2017.

But, the $1 savings will continue all six years as the current rates are already set to increase each year over the same period.

The rates for residential customers outside city limits are 22 percent higher in each category: $48.29 per month in 2012 and $64.62 in 2017. Commercial rates, which are also set to increase annually under the existing schedule, will not be affected.

Also being recommended is the creation of a new customer class for low-income seniors and citizens. Those who qualify would see their monthly billing fee reduced by 50 percent.

All of the rates are based on a comprehensive study Stringer performed over the past year and a half. It examined everything from the current state of the city’s water system and needed capital projects to a close look at other municipal water rates and water usage by Langley residents.

The study identified that planned expenditures will exceed revenues by about $15,000 by the end of 2012. While the proposed rate schedule would bring in some additional money, it would only be enough to fill that hole.

Capital projects included on the comprehensive water system plan have been in the works for years, but lack of funding has kept them from completion. They include the replacement of seven old and under-sized water mains and the continuation of efforts to promote water conservation.

Stringer will attend Thursday’s open house to field questions. The issue will go before the city council on

May 21 as a public hearing.