3.6. GROUNDWATER RESOURCES

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1 3.6. GROUNDWATER RESOURCES Existing Setting Alluvial groundwater basins provide approximately 77% of water required by residential, commercial/industrial and agricultural uses within Santa Barbara County, according to the County Water Agency (2004 Santa Barbara County Groundwater Report). There are 11 major groundwater basins found throughout the County (see Figure 3). Table provides their geographic extent, location relative to the rural regions and current surplus or overdraft condition. None of the major basins are found underlying the Gaviota rural regions, although bedrock groundwater aquifers are found there and elsewhere along the South Coast. A portion of the Santa Maria Basin extends into San Luis Obispo County, and only a small portion of the Cuyama Basin is within Santa Barbara County. Table Groundwater Basins of Santa Barbara County Groundwater Basin Basin Area (w/in SB Co) Surplus or Overdraft Rural Regions % GWB w/in Rural Region Buellton Uplands 14,097 Surplus Lompoc Valley Santa Ynez Valley Carpinteria 8,501 Surplus South Coast Cuyama 133,241 Overdraft Cuyama *45.6 Goleta 13,793 Adjudicated/Managed South Coast Lompoc 20,443 Surplus Lompoc Valley *65.1 Lompoc Uplands 27,414 Overdraft Lompoc Valley San Antonio Creek *98.0 *0.2 Montecito 3,403 Surplus South Coast San Antonio 68,115 Overdraft San Antonio Creek Santa Maria Valley Santa Ynez Valley *81.3 *3.3 *5.2 Santa Barbara 9,208 Managed South Coast Santa Maria 134,593 Overdraft San Antonio Creek Santa Maria Valley *1.3 *83.4 Santa Ynez Uplands 91,116 Surplus San Antonio Creek Santa Ynez Valley *These basins do not total 100% because the basins extend beyond County boundaries and/or also underlay the Los Padres National Forest or Vandenberg Air Force Base. Sources: Santa Barbara County Water Agency Division, 2004; Planning and Development GIS Section, 2004; Personal communication from Brian Baca, County Geologist, As indicated in the above table, four of the 11 basins are in a state of overdraft. Overdraft is defined by the County Water Agency as the level by which long-term average annual demand exceeds the estimated Safe Yield of the basin and thus, in the long term, may result in significant negative impacts on environmental, social or economic conditions (County Water Agency, 2004) Safe yield is defined as the estimated average annual recharge to the basin. 3.6 Environmental Impact Analysis 3.6-1

2 3.6.2 Thresholds of Significance The Groundwater Thresholds Manual (1992) 1 has been adopted by the Board of Supervisors into the Santa Barbara County Environmental Thresholds and Guidelines Manual. The Groundwater Thresholds Manual (GTM) sets forth the manner in which the estimated effects of a proposed project on water resources is evaluated in an environmental document prepared pursuant to CEQA. Based on a formula included in this manual, a threshold of significance is established for each alluvial groundwater basin. This threshold is an amount of annual water demand, reported in acre-feet per year (AFY), which is considered to represent a project-specific significant impact on water resources. If the estimated water demand (i.e. the estimated increase in the consumption of groundwater) of a proposed project exceeds the threshold established for the basin, impacts on water resources are considered potentially significant. Absent effective mitigation measures to reduce the water demand below the threshold value, impacts on ground water resources would be deemed significant and unavoidable. The thresholds of significance presented below have been updated to reflect current (2004) conditions for the alluvial groundwater basins considered by the County to be in a state of overdraft 2. Table Overdrafted Groundwater Basins and Thresholds of Significance Overdrafted basins Thresholds of Significance (AFY) Cuyama 31 Lompoc 25 San Antonio 23 Santa Maria 67 The County s GTM states: No threshold is established for a basin in a state of surplus. A project in such a basin would be subject to a threshold only if it would use more than the remaining surplus. Substantial effects to water resources in the groundwater basins estimated to be in a state of surplus are not anticipated. In the case of bedrock aquifers, it is not anticipated that major facilities would be proposed based on a bedrock aquifer water source. This is because of the generally limited safe yield of these aquifers and the mountainous terrain where such aquifers are accessible. In any case, adopted interpretive guidelines for Land Use Development Policy No. 4 would preclude approval of a project based on overdraft of a bedrock aquifer. Thus, the potential impact of the proposed Uniform Rules modifications will be evaluated for the above-listed alluvial basins. On August 3, 2005, the Court in the Santa Maria Groundwater Litigation approved and filed an Order Approving Settlement Stipulation, finding, among other things, that the Stipulation was reasonable and provided a physical solution to actual and potential problems of the groundwater basin that protects the 1 Brian Baca, Registered Geologist, Groundwater Thresholds Manual for Environmental Review of Water Resources in Santa Barbara County, revised and updated August 20, Brian Baca, Personal Communication. 3.6 Environmental Impact Analysis 3.6-2

3 Groundwater Basins in Santa Barbara County Groundwater Basin Incorporated City Uniform Rules Study Area Unincorporated Urban Area Rural Region Boundary Los Padres N.F. 166 Guadalupe 166 CUYAMA VALLEY Miles Santa Maria New Cuyama Cuyama Santa Maria Cuyama Orcutt SANTA MARIA VALLEY 33 Casmalia VANDENBERG San Antonio LOS PADRES AIR FORCE SAN ANTONIO CREEK Los Alamos NATIONAL FOREST 101 BASE Lompoc Lompoc Uplands Lompoc Santa LOMPOC VALLEY 1 Buellton 246 Uplands Buellton Ynez Solvang 154 Los Olivos SANTA YNEZ VALLEY Santa Ynez River Santa Ynez Uplands GAVIOTA COAST Goleta SOUTH COAST Santa Barbara Carpinteria Figure 3 April 4, 2005 AR14MAPS/AgPreserves/uniform_rules_GWB_color.mxd 101 Goleta Santa Barbara Montecito Carpinteria

4 water resource and rights and interests of all parties by ensuring the Basin s long-term sustainability. The Court approved the Order pursuant to Article X, 2, of the California Constitution in order to impose a physical solution, finding that unless it did so, potential changes in water use could affect Basin adequacy and integrity. In doing so, it required, consistent with the requirements of Orcutt Community Plan Policy WAT-O-2 that new urban uses provide a source of supplemental water to offset the water demand associated with that development, and reserved jurisdiction to supervise the Settlement, including other provisions for new developed water and to respond to severe water shortages. The County 2005 groundwater report has been recently accepted by the Board of Supervisors. This most recent groundwater report reaffirms the overdraft status of the Cuyama, San Antonio and Santa Maria basins; the Lompoc Uplands Basin is reported to have achieved equilibrium. The 2005 report states: Litigation regarding the status and use of groundwater in the Santa Maria Basin was initiated in This litigation may affect the rights of water users within the basin and may result in development of a management process. When final judgment is entered in this litigation, a subsequent ground-water report will contain a discussion of its implications to the groundwater resources monitored by the County. The Water Agency has evaluated the status of the basin, as well as the USGS, DWR, and private entities. Most all parties have agreed historically that the basin is in overdraft to a small, but significant amount. Any amount of overdraft in the basin is significant because overdraft may contribute to water quality changes; not only the buildup of nitrates, sulfates and total dissolved solids, but the threat of salt-water intrusion. SBCWA has an extensive network of water level monitoring wells throughout the basin and when utilized to calculate the storage of groundwater they show that there is indeed a long-term decline in the amount of stored water above sea level in the basin. Whatever the outcome of the litigation, SBCWA staff will continue monitoring the basin and sharing any information collected to all parties interested in protecting its water supply for the continuation of the extensive and historical agricultural base as well as urban usage and development. (SBCWA Groundwater Report 2005, page 55.) Project Impacts Incremental development resulting from the revision to the Uniform Rules would happen over a long period of time. This analysis concentrates on whether or not any one potential project resulting from the proposed Rules could exceed the thresholds. 3.6 Environmental Impact Analysis 3.6-5

5 Changes to Uniform Rules that could impact groundwater resources of the County are those that allow for additional development on contracted land: uses such as residences, tourism, and large-scale wineries and agricultural preparation or processing facilities. The GTM contains water duty factors for land uses such as residential, commercial or industrial, that are used to estimate the amount of water that could be required for new development resulting from the proposed changes to the Uniform Rules. 3 Uniform Rule Principal Dwelling County-wide, the average residential consumptive water demand is about 1.0 AFY for a single family unit located on a lot of approximately 1 acre in size 4. A single residential dwelling on a parcel would not exceed the groundwater thresholds for any of the basins in overdraft. Uniform Rule 2-4. Small-Scale Guest Ranches In Section 2.4 of the Project Description it is estimated that about 25 small-scale guest ranches could result from proposed amendments to the Rules. Five of the guest ranches could be small-scale located on parcels 40 to 100 acres in size and 20 could be larger-scale (up to 6 rooms and 15 guests) on parcels 100 acres or greater. A water-duty factor for hotel/motel with restaurant of 0.24 AFY per room is used to assess water demand by small-scale guest ranches. (City of Santa Barbara, 1989.) The smaller smallscale guest ranches are assumed to have no more than two to three rooms available for guests requiring 0.72 AFY and the larger small-scale guest ranches are assumed to have six rooms available requiring 1.44 AFY. Neither size guest ranch would exceed the groundwater threshold for any of the basins currently in overdraft. Uniform Rule Preparation and Processing This Rule amends requirements for three compatible uses: large-scale wineries; large-scale market preparation facilities; and small-scale processing facilities for non-grape produce. Because large-scale market preparation facilities for crops other than wine grapes could be similar in size and operation to the agricultural industries requiring an AIO, both of these facilities are discussed under Rule 2-6 below. Large-Scale Wineries The development scenario used to estimate water demand for large-scale wineries includes: wine production, water use by employees and visitors, and irrigation for landscaped area, which are presented in Table For some land uses the water duty factors have been updated by the County geologist; for other uses, water duty factors from the Uniform Plumbing Code have been applied. 4 Baca, Brian, December 28, Personal Communication with B. Baca, P&D Geologist. 3.6 Environmental Impact Analysis 3.6-6

6 Characteristics: Table Characteristics of Large-Scale Winery Development 1 Winery development site size 20 acres 13 acres 10 acres 7 acres Added facility area (acres) N/A N/A N/A 2 Added production (cases) 800, , ,000 80,000 # of Employees # of Visitors tasting # of Visitors events Landscaped area (acres) 4 4 acres 2.6 acres 2 acres 0.4 acres 1 Employees and tasting visitors for large-scale wineries have been deduced from the Sonoma County winery traffic data. 2 Number of employees is based on estimates identified in Section 3.1 Agricultural Resources and Land Use. 3 Event visitors assume maximum allowed under Winery Permit Process Ordinance Amendment, Landscaped acreage assumes 0.2 acre of landscaping for every 1 acre of site. To calculate water use, this analysis has applied the following water duty factors: 20 gallons of water per day per employee, 9 gallons of water per day per visitor, 15 gallons water per guest at an event including a meal (California State Uniform Building Code, 2003); 3.6 gallons water per case of wine produced 5 (Paul Jenzen, County Senior Environmental Health Specialist, 2005); and 1.5 AFY of water per acre of landscaping per winery (GTM, 1992). These factors were used in the following formulas: Wine production: # cases of wine x 3.6 gallons water/case 325,871 gallons per acre-foot = acre-feet of water used per year (AFY). Employee use: # employees x 20 gal. x 365 days/year = gallons of water/year 325,871 gallons per acre-foot = acre-feet of water used per year (AFY). Visitor use: This was calculated separately for tasting room visitors and special events: - # tasting room visitors per day x 9 gal/visitor x 365 days/year = gallons of water/year 325,871 gallons per acre-foot = acre-feet of water used per year special events per year x 200 guests per event (assumes maximum allowed for Tier 3 wineries by the Winery Permit Process Ordinance) = # special event guests/year x 15 gal water per guest = gallons of water/year 325,871 gallons = acre-feet of water used per year. Landscaping: In the absence of more specific information, landscaped area is assumed to be 0.2 acres per 1.0 acre of winery facility site (0.2 x site acreage) x 1.5 AFY water per acre. This level of water use is the average rate for landscaping which ranges from 1.0 AFY for xerophytes to 2.0 for exotic ornamentals. 5 This is the average amount of waste water per case of wine produced in the wine-making process from the Napa County water duty factors. 3.6 Environmental Impact Analysis 3.6-7

7 The resulting potential water usage is presented in Table below for four different size facilities. The 7 acre facility is assumed to be an expansion of an existing facility by two acres, so the analysis is only for the two additional acres of facility and commensurate production and activities. Table Estimated Future Water Demand for Large-Scale Wineries in Acre-Feet per Year (AFY) Components of water demand Added facility acreage: 20 acres 13 acres 10 acres 2 acres Increased wine production 8.84 AFY 5.74 AFY 4.42 AFY 0.88 AFY Increased # of Employees Increased Visitors tasting Increased Visitors events Increased area of Landscaping TOTAL Given that the established threshold of significance for each of the alluvial groundwater basins considered to be in a state of overdraft is greater than the AFY demand estimate for the largest possible facility, impacts on water resources for these facilities would be adverse but less than significant. Small-Scale Processing Each of the potential 47 small-scale processing facilities anticipated under the proposed changes to the Rules could require an average additional 2.8 AFY. This assumes that each facility includes a commercial kitchen or similar processing facility occupying no more than 10,000 square feet of structural space on an average.75 acre site. The GTM gives water duty factors for various uses garnered from different jurisdiction within the County. Water use for industrial food processing uses is about 0.28 AFY per 1000 sq. ft. For a facility of 10,000 sq. ft., this equates to 2.8 AFY. This level of water use is less than the thresholds for all basins currently in a state of overdraft. Thus, impacts of these facilities on water resources would be adverse but less than significant. Uniform Rule 2-6 Agricultural Industry Overlay The types of agriculturally-related industries that could locate in an AIO are likely to be similar to largescale market preparation facilities such as cooling and packing plants, and would therefore make similar demands on water resources. As explained in Section 3.4 Transportation/Circulation, it is assumed that large-scale market preparation facilities could locate in the Lompoc and Santa Maria regions, while AIO may eventually be established in all but the South Coast, Gaviota and Cuyama regions. Thus it is likely one or more of these large-scale facilities could locate in areas where the groundwater basin is currently in a state of overdraft. 3.6 Environmental Impact Analysis 3.6-8

8 Table Likely Locations for Larger Facilities for Preparing Non-Grape Crops for Market and AIOs South Coast Gaviota Coast San Antonio Creek Lompoc Valley Santa Maria Valley AIO AIO, LS 2 AIOs, LS AIO = Agricultural Industry Overlay; LS = Large-Scale Preparation Facility Santa Ynez Valley Cuyama The size and scale of these larger agricultural industries is estimated to require about a 15acre site. Two of four assumed AIO sites could potentially be 30 acres in size. A comparable existing facility for icing and chilling vegetables on a 15-acre site uses about 72.0 AFY 6. Although some of this water may return to the groundwater basin through percolation of landscaped irrigation, the vast majority of the water used is exported as ice. Thus, for the purposes of this EIR, the net consumptive use is 72.0 AFY for a 15-acre facility and potentially twice that for a 30-acre site. This potential demand for water by large-scale processing facilities would exceed basin thresholds for all of the overdrafted basins. Consequently, allowing for the development of larger market preparation and other agricultural industries either for individual premises or in an AIO, could have a potentially significant impact on groundwater resources. Uniform Rule 2-7. Waste Disposal and Commercial Composting Facilities As previously discussed, the proposed amendment to the Rules to allow commercial composting facilities on land under contract is estimated to result in the establishment of up to two such facilities; one in the San Antonio Region and one in the Santa Maria Region. Each facility would be up to 35 acres in size. Only a few acres would be used for appurtenant facilities like roads, water storage, drainage structures, loading, unloading and maneuvering of trucks, so the majority of the site would be used for the commercial composting operation. This analysis assumes about 30 acres would be dedicated to commercial composting operations. Water is used in the composting process at a rate similar to vineyards 7. In Table 9 in the Groundwater Thresholds section of the County s Environmental Thresholds and Guidelines Manual water use for vineyards in the Santa Maria and Lompoc valleys is about 1.2 AFY. Vineyard water use in the Santa Ynez, Los Alamos and Sisquoc valleys is about 2.0 AFY per acre. This analysis assumes a water use factor of 1.5 AFY per acre for commercial composting. Since commercial composting facilities take place on open land, a certain amount of water would percolate back into groundwater. The water demand is therefore multiplied by a consumptive use factor of 0.75 to allow for a portion of the water returned. Thus each of the likely commercial composting facilities would require about 33.8 AFY. Given the likely locations for future commercial composting facilities, the basins most likely affected would be San Antonio and Santa Maria basins both of which are determined to be currently in a state of overdraft. Proposed commercial composting facilities could result in potentially significant impacts to groundwater resources for the San Antonia Creek basin since water demand could exceed the groundwater basin safe yield threshold. Uniform Rule Temporary Filming and Special Events 6 Bonita Cooling and Packing Co. Santa Maria, Final EIR (91-EIR-1), April In response to a County staff query in March 2005, the company confirmed that they are still using similar technology and while some expansion to plant has occurred, water use rate is roughly the same as in Tish Beltranena, Presentation to APAC, February 2, Environmental Impact Analysis 3.6-9

9 Special events on premises other than wineries are not expected to generate a significant demand for water, but would in some cases be similar to those events held at wineries. The Zoning Ordinance regulations would allow attendance at non-winery events up to 300 people, or 50 percent more than at winery events. The potential water use at such an event, which under the Zoning Ordinance could extend over five days, would be about 22,500 gallons of water, or 0.07 AFY. This would be an adverse but less than significant impact to groundwater resources. Summary of Project Impacts Impact GW-1: Water demand exceeding groundwater basin safe yield thresholds. Water demand for large-scale preparation facilities proposed to be allowed under Rule and similar industries located within an AIO allowed under Rule 2-6 could exceed safe yield thresholds for basins in a state of overdraft which would be a potentially significant impact. (Addresses Uniform Rules: 2-2 Agricultural Support Facilities and 2-6 Agricultural Industry Overlay). The amount of water needed for a commercial composting operation, proposed to be allowed under Rule 2-7 could similarly exceed thresholds for the overdrafted San Antonio groundwater basin and would be potentially significant. (Addresses Uniform Rule: 2-7 Waste Disposal and Commercial Composting Facilities) Mitigation Measures Existing Policies and Development Standards that May Reduce Impacts There are existing policies in the County s Comprehensive Plan and Local Coastal Plan (LCP) that address protection and conservation of groundwater basins. Policies in the Groundwater Supplement to the Conservation Element state, for instance, that the County shall not allow, through its land use permitting decisions, any basin to become seriously overdrafted on a prolonged basis (Policy 3.5, p. 57). While these policies outline planning goals, they do not constitute or identify feasible mitigation measures to reduce or avoid impacts to groundwater resources. Proposed Mitigation Measures No feasible mitigation measures have been identified that would reduce impacts of the water demand associated with proposed large-scale market preparation facilities, similar facilities located within an AIO and commercial composting facilities. While such facilities could be mandated to be reduced in area, the remaining facility size may not be sufficient to accomplish the purposes of that component of the program. 3.6 Environmental Impact Analysis

10 3.6.5 Residual Impacts Residual impacts of the proposed changes to the Uniform Rules are as follows: Impact GW-1: Water demand for future large-scale preparation facilities serving individual contract holders or as a regional facility in an AIO, and commercial composting facilities would potentially exceed the threshold of significance established for the Lompoc, San Antonio and/or Santa Maria groundwater basins. These impacts represent a significant and unavoidable impact (Class I) of the project on water resources. 3.6 Environmental Impact Analysis