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Water Treatment & Distribution

The City of Ocean Shores water system is a Group A Public System owned and operated by the City. The System is self sufficient in that it produces 100% of the potable water and fire protection service delivered to the 12 square mile service area that is coincidental with the City's corporate limits. Service is provided to approximately 6,000 connections including permanent single family residents, seasonal summer homes, hotels, condominiums, commercial establishments and recreational facilities. Our constant goal is to provide you with a safe and dependable supply of drinking water at a reasonable cost.
Water Source
The City owns a number of wells from which it draws its water supply. The primary source of water comes from a shallow aquifer located approximately 95 feet below the surface.
Water Treatment Process
The City's water is treated using a new (2011) state-of-the-art 2.0 million gallons per day (MGD) water treatment plant. Chlorine contact time is achieved in a 3.0 million gallon tank located next to the water treatment plant. The water treatment process uses MIEX® technology to removed dissolved organic carbon, iron, and manganese from the groundwater.

Water Treatment Plant BuildingThe public works department recently installed (2016-2017) a large steel building over the entire treatment plant in order to protect the infrastructure from the salt of our marine environment.

Filtration and Magnetic Ion Exchange
In 2010 the treatment plant underwent a substantial upgrade to replace filtration equipment and incorporate magnetic ion exchange (MIEX) technology for treating naturally occurring organic compounds. A fairly new and advanced form of treatment, the MIEX system utilizes mixing tanks to combine water that has passed through greensand filtration with a resin that bonds with organic compounds. After approximately 30 minutes of mixing the resin is then filtered out, taking the organic compounds with it. Chlorine gas is then used to disinfect the water prior to its storage in the 3.0 MG tank located at the treatment plant site.
System Control
Treatment plant operation is controlled through SCADA and PLC controllers and production is dictated by the level of water in the 3.0 MG storage tank. The diagram below illustrates the major elements of the water treatment plant and the process flow.
Water Storage
The Ocean Shores system contains four water storage tanks designed to provide fire protection, standby, and equalizing storage to accommodate peak demands. Three of the tanks (North, Central, and South) each have a capacity of 1.0 MG. The North and South tanks are concrete on-grade structures while the Central tank is a welded steel on-grade structure. The fourth tank is a 3.0 MG, welded steel structure located to the south of the main treatment plant buildings on the City’s water operations site near the center of the system. All water from the storage tanks is pumped to the constant pressure distribution system. As such, the entire volume of water in the tanks is available in the event of a fire or sustained high demand event. Typically, however, the tanks are operated within a smaller range to reduce pumping costs and preserve emergency storage volumes.

Water Distribution
The water system depends on constant pressure pumping to maintain domestic water service at an acceptable pressure range and on high capacity pumps for high demand events such as a fire suppression event. Pumping facilities are located at each of the four storage tank sites and are controlled by the SCADA system headquartered at the water system operations center at the water treatment plant. The North and South Tank sites are each equipped with three electric-drive domestic booster pumps, two high capacity diesel-drive fire pumps (with battery backups) and a diesel-powered emergency generator. The Central tank site is equipped with two domestic booster pumps, but no fire pumps.

The system relies on a pressure-sustaining control system to operate the high service pumps and maintain a nearly constant system pressure of 65 psi throughout the entire service area. As noted, the domestic service pumps deliver water from existing storage facilities as needed in emergency situations. Treated water enters the system from service pumps to the 3.0 MG tank.

The distribution system water mains range in diameter from 4 to 16 inches and is mostly constructed of Asbestos Cement (AC) pipe. As discussed under the water system history, the system was developed from north to south under a series of Utility Local Improvement Districts (ULIDs). Generally speaking, water mains installed in northern portion of the City are 6-inch and 8-inch mains. The newer, southern portion of the water system is primarily 8-inches in diameter, presumably because water system sizing standards became more stringent before this area of the system was developed. Larger pipe sizes occur with a 16-inch main on Marine View Drive and 10-inch and 12-inch mains located in the Northeast corner of the City. In all but a few cases, the 4-inch mains are limited to cul-de-sacs and dead-end courts and extend beyond fire hydrants. The current pipe network is just under 528,000 feet or 100 miles of primarily AC water main.
Water Use Efficiency
The City has adopted a Goal for Water Use Efficiency as part of the Water System Planning process. The State’s Municipal Water Law requires public water utilities to adopt a measurable goal for water efficiency, and track its progress towards meeting the goal. This new requirement is fulfilled as a part of the Ocean Shores Water System Plan Update. The Water System Plan defines our goal as 1% reduction per household per year. As part of the Water Use Efficiency Rule, Ocean Shores has been closely monitoring the Distribution System Leakage (DSL) rate which is required to be under 10% over a three year running average.

Water used by the City in its operations can include flushing for water quality, fire hydrant testing, tank cleaning, and water used for the treatment process. These uses do not count towards the system’s DSL. Water Department staff has been accounting for these water uses, and the DSL rate reported in previous years to DOH has been consistently around 13% for the last three years. In August of 2017, the City conducted leak detection work through a majority of the distribution system, with the intent of reducing our DSL.

The City provides Annual Water Quality Reports that summarize the water production data for the City and indicate the amount and percentage of the Distribution System Leakage.
As part of our Water Use Efficiency program, we have water conservation kits available for purchase at our Utility Billing Office (located at 800 Anchor Avenue). Please do your part to help conserve water.