Chapter 16D.09


16D.09.01    Purpose and Intent.

16D.09.02    Mapping.

16D.09.03    Protection Approach.

16D.09.01 Purpose and Intent.

(1)    The Growth Management Act (RCW 36.70A) requires local jurisdictions to protect, through designation and protection, areas with a critical recharging effect on aquifers used for potable water, or areas where a drinking aquifer is vulnerable to contamination that would affect the potability of the water. These areas are referred to as critical aquifer recharge areas (CARA) in this title.

(2)    Potable water is an essential life sustaining element. Much of Yakima County’s drinking water comes from groundwater supplies. Once groundwater is contaminated it can be difficult, costly, and sometimes impossible to clean up. In some cases, the quality of groundwater in an aquifer is inextricably linked to its recharge area.

(3)    The intent of this chapter is to:

(a)    Preserve, protect, and conserve Yakima County’s CARA from contamination;

(b)    Establish a protection approach that emphasizes the use of existing laws and regulations, and minimizes the use of new regulations.

(4)    It is not the intent of this chapter to:

(a)    Regulate everyday activities (including the use of potentially hazardous substances that are used according to State and Federal regulations and according to label specifications);

(b)    Enforce or prevent illegal activities;

(c)    Regulate land uses that use or store small volumes of hazardous substances (including infield agricultural chemical storage facilities, which do not require permits, or are already covered, under existing state, federal, or county review processes and have detailed permit review);

(d)    Establish additional review for septic systems, which are covered under existing County review processes and have detailed permit review by another agency;

(e)    Establish additional review for stormwater control, which are covered under existing County review processes and have detailed permit review; or

(f)    Require review for uses that do not need building permits and/or zoning review.

The above items are deemed to have small risks of CARA contamination or are beyond the development review system’s ability to control.

(Ord. 14-2007 § 1 (Exh. A) (part), 2007).

16D.09.02 Mapping.

(1)    Mapping Methodology. The CARA are depicted in the map titled “Critical Aquifer Recharge Areas of Yakima County.” The CARA map was developed through a geographic information system (GIS) analysis using the methodology outlined in the Washington Department of Ecology “Guidance Document for the Establishment of Critical Aquifer Recharge Area Ordinances” (Publication No. 97-30). Yakima County has determined this analysis to be the best available science at the time the analysis was conducted. This analysis was at a coarse, countywide scale, rather than a site specific assessment. The approximate location and extent of critical aquifer recharge areas are shown on the map, and are to be used as a guide for the county, project applicants and/or property owners, and may be updated as more detailed data becomes available. The CARA map estimates areas of moderate, high and extreme susceptibility to contamination, in addition to wellhead protection areas. To characterize hydrogeologic susceptibility of the recharge area to contamination, the GIS analysis used the following physical characteristics:

(a)    Depth to ground water;

(b)    Soil (texture, permeability, and contaminant attenuation properties);

(c)    Geologic material permeability;

(d)    Recharge (amount of water applied to the land surface, including precipitation and irrigation).

(2)    Wellhead Protection Areas. The CARA map includes those wellhead protection areas for which the County has maps. Wellhead protection areas are required for all Class A public water systems in the state of Washington. The determination of a wellhead protection area is based upon the time of travel of a water particle from its source to the well. Water purveyors collect site specific information to determine the susceptibility of the water source to surface sources of contamination. Water sources are ranked by the Washington State Department of Health with a high, moderate or low susceptibility to surface contamination. Wellhead protection areas are defined by the boundaries of the ten (10) year time of ground water travel, in accordance with WAC 246-290-135. For purposes of this chapter, all wellhead protection areas shall be considered highly susceptible.

(Ord. 14-2007 § 1 (Exh. A) (part), 2007).

16D.09.03 Protection Approach.

(1)    Maps shall be used only as an informational resource to communicate with applicants on potential problems with meeting the applicable laws on a particular site. The maps indicate that high susceptibility areas tend to be located in the valley bottoms and follow along floodplain and stream corridors, with the extreme susceptibility locations being largely within floodplains, and along streams and wetlands.

(2)    Land uses are subject to many existing federal, state, local, or tribal laws regarding the handling of substances that may contaminate CARAs. Additional regulatory standards by Yakima County are not needed. Disclosure, educational information, and coordination of existing laws during existing review processes can accomplish the requirement to protect Critical Aquifer Recharge Areas. Consequently, Yakima County’s protection of CARA shall be accomplished through normal project permit review under various Yakima County Codes, especially the stream protection standards in Chapter 16D.06 (Fish and Wildlife Habitat and the Stream Corridor System), including section 16D.06.10 (Prohibited Uses); the Shoreline Use Table in section 16D.10.05 and YCC Title 13 (Building and Construction Code), which provides detailed construction, use, and fire/life-safety standards for the storage and handling of dangerous and hazardous substances to a greater extent than most existing state and federal laws.

(3)    The administrative official shall develop and maintain a list of the relevant laws noted above. This list shall be informational, and is intended to be used in coordination with development permit review. This list shall be periodically reviewed and updated so as to provide the most comprehensive list possible to inform project applicants of the requirements of other agencies.

(4)    The administrative official shall also develop and maintain a table of land uses with the potential of being subject to the relevant laws noted above. The table shall be generated and maintained using the intent stated in 16D.09.01(4) (Purpose and Intent).

(5)    The administrative official and Building Official shall cooperatively develop questionnaires, to be filled out by new development permit applicants, which comprehensively establish the potential use, storage, and handling methods within the project for substances that have the potential to contaminate groundwater. The questionnaires are intended to ensure full application of existing building and construction codes related to such substances in order to forestall new regulations.

(6)    The administrative official and Building Official shall develop technical assistance and information materials to assist landowners and developers with understanding and meeting relevant existing federal, state, and local laws relating to CARAs.

(Ord. 14-2007 § 1 (Exh. A) (part), 2007).