What is the Issue?

The issue is the use and impact of exempt wells on water resources in the Chehalis Basin.

What are the rules related to exempt wells?

Washington State's Groundwater Code, RCW 90.44.050 requires anyone who wants to withdraw public groundwater to apply for a permit through the State Department of Ecology (Ecology). The Code allows exceptions for certain specific uses:

Stock watering (note: amounts used for this purpose may exceed 5,000 gallons per day; citation forthcoming)

Watering a lawn or non-commercial garden not exceeding one-half acre in area

Single or group domestic uses of up to 5,000 gallons per day

Industrial use not to exceed 5,000 gallons per day

Wells drilled under this provision are commonly referred to as "exempt wells." The exempt well statute provides a means by which landowners may access water for domestic purposes, including small-scale irrigation and industrial purposes, without complying with regular procedures. The exemption saves the appropriator of "small withdrawals" the trouble and expense of applying for a permit where the impact of the withdrawal is slight, and saves the state the trouble and expense of processing applications for "small withdrawals" that would have little effect on water availability.

While small withdrawals are exempt from the requirements that an application by made and a permit received from Ecology prior to withdrawal of public groundwater, they are not exempt from any of the other substantive provisions of the Ground Water Code. For example, small withdrawals

Cannot affect surface water rights

Cannot be wasted without economical beneficial use

Are subject to the same system of priorities as all other appropriators (that is, where another right is first in time, it is first in right)

Domestic, in-house use of exempt wells is exempt from the minimum instream flow rule WAC 173-515-050. This means instream flow levels cannot affect domestic, in-house uses of exempt wells.

Why are exempt wells a concern?

Exempt wells affect water quantity, a required element of watershed planning. They can also have impacts on the three remaining elements in the Chehalis Basin Watershed Plan: water quality, habitat, and instream flows. The concern is that exempt wells and the associated uses can reduce senior water right volumes, lower stream flows, and generally negatively affect water quantity, quality and habitat. The proliferation of exempt wells reduces the total amount of water available in the Chehalis Basin. As each additional exempt well is drilled, water quantities dedicated to aquifer recharge, instream flows, and other water use can be reduced.

The relationship between groundwater and surface water sources is affected by groundwater pumping, which may intercept water otherwise available to recharge a stream or capture water from the stream itself. A watershed assessment conducted by Ecology in 1995 confirmed the hydraulic continuity between ground and surface water in the Chehalis Basin and concluded that a large portion (if not most) of the groundwater allocated since 1975 directly affected surface water flows. The construction of exempt wells in aquifers that are in hydraulic continuity with flow impaired surface waters will directly result in further depletion of surface water flows.

Studies conducted by the U.S. Geological Survey and the Department of Ecology, coupled with data from local governmental agencies, reveal the following health concerns associated with exempt wells:

Exempt wells can be contaminated by withdrawal of water from contaminated aquifers.

Pumping can cause saltwater intrusion along the coast.

Nitrates from agriculture can contaminate the groundwater.

Exempt wells are also quite susceptible to contamination from wastewater, typically septic tank/leach field systems. The proliferation of exempt wells has exacerbated this public health problem

What is the effect of exempt wells on water quantity in the Chehalis Basin?

At present, information related to the number of exempt wells in the Chehalis Basin is limited. However, technical work completed as part of the watershed planning process provided estimates of the number of households on exempt wells, the amount of average annual daily water use per household and associated consumptive use, and the overall impact of exempt wells on water quantity and instream flows in the basin. GIS information suggests high concentrations of exempt wells exist in areas where stream flows already do not meet regulatory minimums; these wells may have an impact on stream flows.

Figure 1 (Exempt Well Consumptive Water Use) illustrates the amount of water used by various household activities. It also illustrates the amount of water that is consumed, or does not make it back to groundwater after use, by a household that draws water from an exempt well and returns water through a septic system and drain field. The daily household water use estimate was based on the assumptions that indoor and outdoor water use represent 59% and 41%, respectively, and that 87% of the indoor water use and 57% of the outdoor water use make it back into the groundwater.

The consumptive water use estimate provides a general picture of consumptive water use. Some households use more water than others and water use, in general, is higher during certain months of the year (primarily summer irrigation months when stream flows are lowest). Therefore, it is important to consider the relationship between the needs of specific streams, especially during certain months, and the amount of consumptive use in the sub-basins hydraulically connected with those streams.

Figure 2 (Map of Distribution of Exempt Wells in Chehalis Basin) shows the boundaries of the public water systems and a range of numbers of households on exempt wells for each sub-basin.

The number of households on exempt wells was estimated by WRIA and sub-basin in the following manner: population was estimated on a density per acre basis for areas outside water service areas; this estimated population was divided by 2.5 persons per household to determine a number of households per sub-basin not supplied by public water or the potential demand for residential water connections; then this number of potential water connections was then decreased by the estimated number of connections available by water right. The result was a number of households on exempt wells.

The following sources were used in the process described above:

GIS maps from Lewis, Thurston, and Grays Harbor Counties and hard copy maps from a number of water districts. Where boundary information was not available, estimated boundaries were developed based on incorporated area, urban growth area, or aerial photographs.

WRATs data, section and sub-basin GIS maps, shape files of priority one group rights, and other base map shape files from EPA

2000 Census GIS maps from the State Department of Health and State Office of Financial Management

Maps of wells from Department of Health and Lewis County (these were examined but not used)

Level 1 Assessment report information

Aerial photographs and other GIS data from Chehalis Basin Partnership >

FIGURE 1: Consumptive Water Use of Household on Exempt Well1

FIGURE 2: Exempt Well Distribution in Chehalis Basin

Estimates of Households on Exempt Wells and Related Water Use in Chehalis Basin

Number of households on exempt wells

An estimated 16,947 households draw water from exempt wells in the Chehalis Basin.

Average amount of water use per household

Estimated across the entire Chehalis basin, an average residential household uses approximately 334 gallons per day (gpd) of water during the summer (period of highest use).

Amount of consumptive water use per household

For households on exempt wells approximately 85 gpd (of the 334 gpd used) constitutes consumptive water use. This means that 85 gpd of the water draw from the exempt well does not return to the water source (ground or surface water).

Amount of water use and consumptive water use from exempt wells in Chehalis Basin

The 16,947 households on exempt wells in the Chehalis Basin constitute 5,660,298 gpd (8.25 cfs) of water use or 1,440,495 gpd (2.23 cfs) of consumptive water use. NOTE: this does not include agricultural, industrial, commercial or stock watering.

Further review should be conducted to evaluate the sensitivity of the estimate to the various factors and assumptions.

Table 1: Estimated Population and Households Served by Public Water Systems, Water Rights and Exempt Wells

-	Lower Chehalis	Upper Chehalis	Lower/Upper Chehalis
Estimated Total Population	62,452	78,779	141,231
Estimated Population Served by Public Water System	36,427	38,064	74,491
Estimated Population Not Served by Public Water System	26,025	40,715	66,740
Estimated Households Not Served by Public Water System	10,844	16,965	27,809
Estimated Households Served by Water Right	3,013	7,849	10,862
Estimated Households Served by Exempt Wells	7,831	9,116	16,947

What are possible solutions?

The CBP evaluated the following options related to exempt wells, arrayed from least to greatest impact:.

Alternative Solutions	Expected Outcomes	Comments
Status Quo	Continued use of existing exempt wells, Proliferation of new exempt wells, Lack of focus on community systems	-
White Paper on proliferation of exempt wells vs. community systems	Providing policy makers with information on the impacts of exempt wells, especially on ability to manage growth	-
Study of the quantity of water loss Collect data to refine consumptive use estimates and assess the effect on the timing of use.	Development of understanding of consumptive use levels of exempt wells to better understand impacts on base flows	-
Request to DOE to address the exempt well issue on a statewide basis	Statewide consistency in addressing exempt wells, both existing systems and future wells	-
Allow exempt wells with conditions. Some suggestions to consider include: Set basin-wide standard for number of houses allowable per exempt well Reduce exemption amount from 5,000 gpd, since most homes use only 3-400gpd (WA Dept. of Health allotment is 800 gpd for development) Require septic tank/leach field discharge back to aquifer Conserve water Limit numbers to one septic field or equivalent residential unit per exempt well Define allowable consumptive use Require exempt wells to connect to deep aquifers OR allow connection to shallow ones if study is done to show no negative impact on stream flows Others?	Ability to use exempt wells but with conditions that will lessen losses of water and depletion of stream flows	The real question remains : How do we encourage new residents to use purveyor systems instead of exempt wells when new residents cannot get onto a purveyor system in a reasonable time frame (i.e. planned and coordinated growth, including impacts on environment)
For exempt well problem areas, identify/develop mitigation (e.g. convert to public water system)	Lessening of impact on stream flows	-
Identify a density trigger where exempt wells are not allowed above a certain level (What level is trigger?)	Control of number of exempt wells and therefore shifting of focus to community systems	Relate to stream flow levels?
Prohibit exempt wells in closed basins	Assurance that exempt wells will not negatively impact stream flows	-
Do not allow new exempt wells through regulatory approach or stipulation that UGA's/Growth areas would not allow exempt wells	Focus on community systems Better focus on drinking water quality Better focus on growth controls	Property takings would be an issue

Recommendations

Until the steps below are taken, maintain the status quo with regard to exempt wells.

The CBP believes that exempt wells are a statewide issue, caused in part by the fact that the Department of Ecology has not enforced existing laws and requirements or followed the Attorney General's 1998 opinion on exempt wells. The CBP therefore recommends that Ecology address the exempt well issue on a statewide basis following the existing laws, rules, and opinions (see bullets below). Alternative solution 4 above is the prime recommendation from the Chehalis Basin.

Regulations:

State enforce current regulations

Evaluate current regulations on exempt wells for adequacy in protecting surface waters (quantity and quality)

Clarify and resolve the science around the impacts of exempt wells to surface water

If local governments are to have a role in managing exempt wells, State resources must be allocated for this.

The CBP believes that the Department of Health should prepare a white paper on the proliferation of exempt wells and their impacts on reducing community water systems, resulting in regulatory and water quality concerns.

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