Martindale, Dick, Panhandle Health District, 2195 Ironwood Court, Coeur d'Alene, ID 83814
The Spokane Valley-Rathdrum Prairie Aquifer (aquifer) formed during the last ice age, 12,000 to 20,000 years ago, when massive floods spread across northern Idaho and eastern Washington. The Spokane Floods occurred when an ice dam holding back 500 cubic miles of water in Glacial Lake Missoula broke; waters raced across the land dropping sands, gravels and boulders. Scientists believe these floods may have occurred dozens of times. The aquifer lies below the land surface of 325 square miles of northern Idaho and eastern Washington, and is the sole source of drinking water for the region's 400,000 people. The aquifer is composed of glacial outwash (sands, gravels and cobbles). It is extremely permeable, high in groundwater velocity and susceptible to contamination.
In the 1970s, both northern Idaho and Spokane County obtained grants under Section 208 of the federal Clean Water Act to pursue studies aimed at developing management plans for the aquifer. These studies began with well sampling networks. In all, hundreds of wells were sampled in the two states. The results of a year of monitoring showed the water quality was still good, but definite trends of deterioration could be attributed to human activities on the ground surface above. In 1978, the Spokane Valley-Rathdrum Prairie Aquifer was declared a "sole source" drinking water supply pursuant to Section 1424e of the federal Safe Drinking Water Act (P.L. 93-523).
Since the completion of the 208-funded aquifer protection plans, Spokane and northern Idaho officials and citizens have worked to implement an integrated protection program. Aiding significantly in this effort was a 1988 congressional appropriation of one million dollars to Spokane County, Washington, the Idaho Division of Environmental Quality (DEQ) and the Panhandle Health District, Idaho (PHD). Federal funding continued for seven more years as programs were implemented to manage wastewater, chemicals, solid waste, stormwater runoff, and aquifer recharge areas. Federal funding is no longer available, and other sources must be identified and pursued.
In September of 1996, staff from PHD and DEQ invited 19 members of the public to participate in a process to identify the programs that are most effective at protecting the aquifer, and to make recommendations on how to implement those programs without the use of federal funds. After nine months the committee, which was represented from all sectors of the community, finalized a set of recommendations that supported programs at the local level and provided direction on funding alternatives.
MacInnis, James D., Jr., and Painter, Brian D., Idaho Division of Environmental Quality, 2110 Ironwood Parkway, Coeur d'Alene, ID 83814-2648
As a result of strong interest from communities in the Coeur d'Alene, Idaho, area, in 1990 the Idaho Division of Environmental Quality (DEQ) selected a consultant to study the environmental effects of slow-rate application of secondary treated municipal wastewater on agricultural land located over the Spokane Valley-Rathdrum Prairie Aquifer. The completed report entitled Rathdrum Prairie Land Application Feasibility Study was cautiously optimistic that land application is an environmentally sound alternative for wastewater treatment over the aquifer: although contaminants may be present in the wastewater, this report suggested that a properly designed, sited and operated system could minimize contaminant migration, producing minimal ground water degradation. DEQ staff realized that successful and environmentally sound slow-rate wastewater land application over the aquifer would require special technical guidelines. In May, 1991 DEQ facilitated the creation of a Technical Advisory Committee (TAC) to provide oversight of the work towards writing the special technical guidelines. The TAC membership included a broad representation from local and regional technical interests: Idaho Panhandle Health District, Kootenai County Soil Conservation District, Soil Conservation District (USDA), University of Idaho Cooperative Extension Service, Spokane County Public Works (in Washington State), EPA (US, Region X), City of Spokane (in Washington State) and several engineering consulting firms representing local municipalities. Frequency of meetings depended on the amount of site activity and varied from monthly, at the start of the project, to about twice a year in late 1993 and 1994. The technical advice and direction from the TAC made the project a success. In 1993 at the direction of the TAC, DEQ commissioned a consultant to report on a wastewater land application pilot study over the Rathdrum Aquifer. This cooperative project between DEQ, the Hayden Area Regional Sewer Board and Spokane County was conducted to demonstrate land application technology and to obtain environmental data to improve the accuracy of the impact assessment and, ultimately, to determine the feasibility of using land application over the Spokane Valley-Rathdrum Prairie Aquifer as a permanent solution to wastewater treatment and disposal. The result of this work, the Hayden Land Application Pilot Study, provides the information necessary to comply with Idaho's water quality regulations for initially establishing best management practices specific to land over the Spokane Valley-Rathdrum Prairie Aquifer. At the end of the two year study, the TAC evaluated the results and directed DEQ staff to prepare special technical guidelines for slow-rate wastewater land application over the aquifer consistent with the results of the study. Upon TAC review and comment of several draft versions, the approved Special Supplemental Guidelines to the Idaho Wastewater Land Application Guidelines were published in January, 1995.
Wick, Ty, Spokane County Water District No. 3, P O Box 11187, Spokane, WA 99211-1187
The 1986 Amendments to the federal Safe Drinking Water Act directed the states (and ultimately water utilities) to develop wellhead protection programs. The goal of these programs is to insure that the groundwater recharge area directly contributing to the water being withdrawn from a public water supply well is protected from contamination. The reason Congress included this requirement was to formally recognize their position that it is much more cost effective to prevent contamination from occurring as compared to the costs of clean up, or replacing and/or treating a contaminated water supply.
Public water supply utilities have always taken measures to protect their groundwater sources (wellheads and wellfields). A state regulation to own and/or control a sanitary zone around each wellhead or wellfield was in place long before 1986.
However, when Washington State mandated that water utilities prepare wellhead protection plans, the local water utilities immediately recognized that the minimum requirement of drawing circles around the wellheads to delineate capture zones did not make sense in the Spokane aquifer. Further, they acknowledged that they do not have any authority to implement wellhead protection plans. Local governments with zoning authority are responsible for land use planning and zoning. Representatives of these local agencies will play a major role in helping utilities protect their community's drinking water supply and in coordinating wellhead protection measures for the multiple utilities in the Spokane area. Utilities are primarily responsible for only the delineation and inventory of wellhead protection areas. Faced with these and other realities, the utilities joined together to form the Spokane Aquifer Joint Board (SAJB). The goals of the SAJB are to accomplish the following: 1) to protect the aquifer and our water rights, 2) to mitigate and eliminate conflicts between water utilities, 3) to ensure coordination of efforts in implementing plans, and 4) to create a unified voice for the water utilities of the Spokane area.
The first effort of the SAJB is to prepare a wellhead protection plan. CH2M/Hill has been selected to work with the SAJB in accomplishing this task. The wellhead protection process includes: 1) data collection, 2) sensitive areas delineation, 3) a contaminant source inventory, 4) contingency planning, 5) public involvement and education, and 6) implementation.
From the utilities' perspective, public involvement and education is the most important element of the program. The public's involvement and support in the determination of management procedures to protect their drinking water supplies from potential sources of contamination is crucial to the acceptance and cooperation of local governments. The success or failure in implementing any wellhead protection program lies in the hands of the local governments with land use responsibilities.
Hendron, Lars H., Environmental Programs, City of Spokane, 808 W. Spokane Falls Boulevard, Spokane, WA 99201; lhendron@spokanecity.org
The City of Spokane is situated in eastern Washington State and overlies a portion of the Spokane Valley/Rathdrum Prairie Aquifer. One of the most prolific aquifers in the United States, it is the source of drinking water for over 300,000 people, 180,000 of which are City residents. The City began planning its Wellhead Protection Program in 1992. To initiate the program, the City developed a two-phase approach: technical assessment and implementation. The Program is patterned after the Washington State Wellhead Protection Program administered by the Department of Health, and is funded in part with a Department of Ecology Centennial Clean Water Grant.
The principal tasks comprising Phase One of the Wellhead Protection Program were collecting data to define the characteristics of the aquifer system; developing a groundwater flow simulation model; preparing a contingency plan for the existing wells; and developing and mapping a regional Contaminant Source Inventory (CSI) to identify potential contaminant threats. The CSI was mapped using the the City's Geographic Information System (GIS). Phase One also involved substantial research of the regional Spokane Aquifer system. The field data collection included installing fourteen groundwater monitoring wells and nine continuous recording level monitors; discrete fall and spring water groundwater level and river level measurement events at some 125 locations throughout the aquifer; groundwater transmissivity testing; and seismic reflection profiling. Through the Phase One data collection activities, a better understanding of this Sole Source aquifer system has evolved, leading to the determination of Wellhead Protection Areas for the City's wellfields. Phase One of the City's Wellhead Program is anticipated to be finished in the spring of 1997.
As Phase One nears completion, the City is preparing to begin Phase Two, the development and implementation of management strategies to protect the groundwater supply. Phase Two includes developing the public outreach program and implementing the management strategies which will be determined via the public and stakeholder involvement. In January, 1997, the City of Spokane, Spokane County, and the Spokane Aquifer Joint Board (a consortium of private water purveyors conducting a wellhead protection project in the Spokane area), agreed verbally to enjoin in a regional implementation program. The City and the Joint Board are currently seeking to coordinate efforts to ensure commonality of the program and public support to protect the quality of this vital resource.