5.8 HYDROLOGY AND WATER QUALITY

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1 5.8 HYDROLOGY AND WATER QUALITY This section of the environmental impact report (EIR) identifies and analyzes regional and local surface water and groundwater resources that could affect or be affected by the Goals, Policies, and Actions presented in the General Plan Update. Specific issues analyzed in this section include the following: stormwater runoff (quantity and quality), flooding, and groundwater recharge. Sources of information to describe existing conditions, and for the analysis, include a variety of regional planning documents. It should be noted that water supply, use, and quality is a highly regulated resource in the arid environment of Southern California. Therefore, an extensive Regulatory Framework discussion is presented as the context upon which the General Plan Update Goals, Policies, and Actions are evaluated Regional Hydrology The Santa Ana River (SAR) is the largest river system in Southern California, originating in the San Bernardino and San Gabriel Mountains with a watershed encompassing 2,450 square miles in San Bernardino, Riverside, and Orange Counties. The upper and lower watersheds are divided at Prado Dam located just east of the Santa Ana Mountains. Below the dam, the river channel passes through the mountains into Orange County, and ultimately reaches the Pacific Ocean between the cities of Newport Beach and Huntington Beach. Most of the river s tributary streams are historically ephemeral, with flow occurring almost exclusively in the winter months in response to heavy precipitation. Major tributaries to the SAR include San Antonio Creek, Chino Creek, San Timoteo Creek, Temescal Creek, Cucamonga Creek, Bear Creek, and Lytle Creek (see Figure 5.8-1). The City of Fontana is located within the lower Lytle Creek watershed, which forms the northwest portion of the Santa Ana River Watershed and drains the eastern portion of the San Gabriel Mountains. Daytime temperatures in the summer months frequently exceed 100 degrees in the lower watershed and are about degrees cooler in the upper watershed. Winter temperatures can fall below freezing throughout the entire watershed. The lower watershed averages inches of rain annually while the upper watershed averages 35 inches annually. The Lytle Creek watershed covers an area of approximately 186 square miles with a mean annual runoff of roughly 31,720 acre feet (af). Lytle Creek is a tributary of Warm Creek, which in turn is a tributary to the SAR, joining the mainstem of the river in the vicinity of Prado Dam. The lower portion of Lytle Creek flows through four cities: in addition to the City of Fontana, the lower watershed includes the cities of Rialto, San Bernardino, and Colton, as well as a portion of the unincorporated area of San Bernardino County. Although the upper reaches of Lytle Creek are generally perennial, the lower section of Lytle Creek changes into an intermittent stream with a dry wash below Interstate 15. The alluvial fan extends roughly from the Glen Helen area in the north, and south to Rancho Cucamonga and Colton. A small portion at the lower edge of the wash is in a concrete channel

2 SOURCE: the Santa Ana Water Project Authority Figure Santa Ana River Watershed 5.8-2

3 5.8.2 Regulatory Framework The following section provides information regarding important regulatory programs related to water resources currently in effect. This section does not list all regulations relevant to hydrology and water quality issues; however, it does outline major programs applicable to the planning area Federal Flood Control The US Army Corps of Engineers (USACE) is responsible for providing flood protection facilities to navigable waters of the United States. The USACE also administers permitting pursuant to Section 404 of the Clean Water Act (CWA) for activities conducted within waters of the United States. Responsibility for flood protection falls under the jurisdiction of the San Bernardino County Flood Control District (SBCFCD) and the Riverside County Flood Control District, as well as local jurisdictions. Floodplain Development The Federal Emergency Management Agency (FEMA) is responsible for determining flood elevations and floodplain boundaries based on USACE studies. The FEMA is also responsible for distributing the Flood Insurance Rate Maps (FIRMs), which are used in the National Flood Insurance Program (NFIP). These maps identify the locations of special flood hazard areas, including the 100-year floodplain. The current FIRM for Fontana was made effective on September 2, Water Quality Section 303 of the federal CWA requires states to adopt water quality standards for all surface water of the United States. Where multiple uses exist, water quality standards must protect the most sensitive use. Water quality criteria are typically numeric, although narrative criteria based upon bio-monitoring methods may be employed where numerical standards cannot be established or where needed to supplement the criteria. The Safe Drinking Water Act (SDWA) and subsequent amendments authorize the Environmental Protection Agency (EPA) to set health-based standards (maximum contaminant levels or MCLs) for drinking water to protect public health against both naturally-occurring and man-made contaminants. The EPA administers the SDWA at the federal level and establishes MCLs for bacteriological, inorganic, organic, and radiological constituents (United States Code Title 42, and Code of Federal Regulations Title 40). California administers and enforces the drinking water program at the State level, and has adopted its own SDWA, which incorporates the federal SDWA requirements including some requirements specific only to California (California Health and Safety Code, Section )

4 State/Region Water Quality The State Water Resources Control Board (SWRCB) was established through the California Porter- Cologne Water Quality Act of 1969 and is the primary state agency responsible for water quality management issues in California. Much of the responsibility for implementation of the SWRCB s policies is delegated to the nine Regional Water Quality Control Boards (RWQCBs). The City of Fontana is located in the Santa Ana Region (Region 8). The SWRCB and the RWQCBs are responsible for ensuring implementation and compliance with the provisions of the federal CWA, including National Pollutant Discharge Elimination System (NPDES) programs, and California s Porter-Cologne Water Quality Control Act. Along with the SWRCB and RWQCBs, water quality protection is the responsibility of numerous water supply and wastewater management agencies, as well as city and county governments, and requires the coordinated efforts of these various entities. Section 402 of the CWA established the NPDES to regulate discharges into waters of the US. The EPA authorized the SWRCB to issue NPDES permits in the State of California in The NPDES permit establishes discharge pollutant thresholds and operational conditions for industrial facilities and wastewater treatment plants. Nonpoint source NPDES permits are also required for municipalities and unincorporated communities of populations greater than 100,000 to control urban stormwater runoff. These municipal permits require the preparation of Stormwater Management Plans (SWMPs) that reflect the environmental concerns of the local community. The Municipal Storm Water Program regulates storm water discharges from municipal separate storm sewer systems (MS4s) throughout California. U.S. EPA defines an MS4 as a conveyance or system of conveyances (including roads with drainage systems, municipal streets, catch basins, curbs, gutters, ditches, man-made channels, or storm drains) owned or operated by a State (40 CFR (b)(8)). Pursuant to the Federal Water Pollution Control Act (CWA) section 402(p), storm water permits are required for discharges from an MS4 serving a population of 100,000 or more. The Municipal Storm Water Program manages the Phase I Permit Program (serving municipalities over 100,000 people), the Phase II Permit Program (for municipalities less than 100,000), and the Statewide Storm Water Permit for the State of California Department of Transportation. The SWRCB and RWQCBs (collectively, the Water Boards) implement and enforce the Municipal Storm Water Program. The City of Fontana lies within the jurisdiction of the Santa Ana Regional Water Quality Control Board (SARWQCB). The SARWQCB implements the NPDES permitting program for the SAR watershed pursuant to Section 402 of the federal CWA. As such, the SARWQCB has the authority to implement water quality protection standards through the issuance of permits for discharges to waters at locations within its jurisdiction. Existing water quality issues have been identified in 5.8-4

5 the watershed planning process and are incorporated in the Water Quality Control Plan (WCQP) for the Santa Ana Basin Plan. The Basin Plan designates beneficial uses of the waters of the region and specifies water quality objectives intended to protect those uses. The Basin Plan also specifies an implementation plan describing actions that are necessary to achieve and maintain water quality standards and regulates waste discharges to minimize and control their effects. Dischargers must comply with the water quality standards contained in the Basin Plan. Section 303(d) of the CWA requires the SWRCB to list impaired water bodies in the state and determine Total Maximum Daily Loads (TMDLs) for pollutants or other stressors impacting water quality. The SAR is listed as impaired for indicator bacteria by nonpoint sources. As noted above, the Basin Plan establishes water quality objectives and implementation programs to meet stated objectives to protect the beneficial uses of water in the SAR and the coastal waters of the Pacific Ocean. Pursuant to Section 303(d) of the CWA, the SARWQCB is responsible for assigning and enforcing TMDLs for impaired waterbodies. Two reaches of the SAR (reaches 3 and 4) were found to be impaired and are listed on the SWRCB s 2002 list of impaired water bodies compiled pursuant to Section 303(d) of the federal CWA. Both reaches are upstream of Prado Dam, and the impairments are primarily attributable to pathogens caused by dairies and other nonpoint sources. Several tributaries to the SAR are listed as impaired for pathogens and nutrients, and some for sediment or heavy metals. General and site-specific water quality standards and criteria are listed in the Basin Plan. Construction Site Runoff Management The SWRCB adopted a statewide general NPDES permit for stormwater discharges associated with construction activity (General Construction Permit) in August Performance standards for obtaining and complying with the General Construction Permit are described in General Permit for Discharges of Stormwater Associated with Construction Activity in the State, NPDES General Permit No. CAS000002; Waste Discharge Requirements (WDR), Order No DWQ. The General Construction Permit was modified in April 2001 (SWRCB Resolution No ) to require permittees to implement specific sampling and analytical procedures to determine whether the best management practices (BMPs) used at the construction site are effective. Under the General Construction Permit, projects that result in disturbance of one or more acres of soil, or whose projects disturb less than one acre, but are part of a larger common plan of development that in total disturbs one or more acres, are required to obtain coverage under the General Construction Permit. Urban Runoff Management The SBCFCD, as well as the County and the 16 incorporated cities within the Santa Ana River Watershed, are Co-permittees under a stormwater discharge permit issued by the State of California through the SARWQCB. The County Flood Control District has been designated Principal Permittee under the MS4 Permit and administers and coordinates many of the permit requirements on behalf of all the Permittees. The Permittees are implementing and complying 5.8-5

6 with the requirements of the latest NPDES MS4 permit (4th iteration) that was issued in January Local San Bernardino County Flood Control District (SBCFCD) The SBCFCD is a division of the San Bernardino County Department of Public Works with responsibility for maintaining the flood control facilities within the SAR channel and other streams in the County, including the levees and concrete linings, and works in conjunction with other flood control agencies in the watershed, including the Riverside County Flood Control District and the Orange County Flood Control District. Santa Ana River Watermaster The Santa Ana River Watermaster is a five-member committee appointed by the court to administer the provisions of the 1969 Stipulated Judgment. The Watermaster is made up of representatives from each of the parties subject to the Judgment and maintains a continuous accounting of storm and base flows, entitlement credits and debits, and water quality data. This information is reported to the court and the parties annually for each water year (October 1 to September 30). SAR flows recorded in the annual Watermaster Report are determined from river gauges managed by the United States Geological Survey (USGS) National Streamflow Information Program. The USGS maintains a SAR flow gauge at the Prado Dam discharge point. The Watermaster Annual Reports present a basic accounting of historic SAR flows. Santa Ana Watershed Project Authority (SAWPA) The SAWPA was created in 1972 as a Joint Powers Authority (JPA) mandated to manage water quality within the watershed for multiple beneficial purposes. The SAWPA s member agencies include San Bernardino Municipal Water District (Muni), Western Municipal Water District (Western), Orange County Water District (OCWD), Inland Empire Utility Agency (IEUA), and the Eastern Municipal Water District (Eastern). The SAWPA s initial action was to prepare the Basin Plan under contract to the SARWQCB. SAWPA recently prepared an Integrated Water Resource Plan (IWRP) for the watershed describing the existing water resources, projected demand, and long-range water quality planning needs for the region. The One Water One Watershed program is the basis of the SAWPA Integrated Regional Water Management Plan. San Bernardino County Municipal Stormwater Management Plan (MSMP) The purpose of the MSMP was to satisfy NPDES permit conditions for creating and implementing an Urban Runoff Management Program (URMP) to reduce pollutant discharges to the maximum extent practicable (MEP) for protection of receiving waterbody water quality and support of designated beneficial uses. The MSMP contains guidance on both structural and nonstructural BMPs for meeting these goals

7 The MSMP identifies activities required to implement the following six minimum control measures required under the Municipal Permit: public outreach; public involvement; illicit discharge detection and elimination; construction site runoff; new development and redevelopment; and municipal operations. Some typical types of outreach may include a stormwater hotline, website, storm drain stenciling, and other programs. Public meetings and presentations, volunteer water quality monitoring groups, and community cleanup days are some of the elements of the public involvement component. One Water One Watershed The One Water One Watershed (OWOW) program, is the result of an integrated planning process convened for the management of the Santa Ana River Watershed. The OWOW program integrates water resources management with various disciplines such as land use planning, flood control, and natural resource management. The OWOW plan is now in its second iteration, which was adopted in The OWOW plan process complies with the standards of the State of California s Integrated Regional Water Management Program while supporting synergies in planning how to address water challenges across the Santa Ana River Watershed. The OWOW 2.0 Plan describes the next generation of integrated regional watershed planning, solving problems on a regional scale, and giving all water interests a voice in the planning process. The plan provides a blueprint for management of the watershed, which includes the following goals: Achieve a watershed that is sustainable, drought-proofed and salt-balanced by 2035, and in which water resources are protected and water is used efficiently; Value a watershed that supports economic prosperity and environmental viability; Assure a watershed that diminishes carbon emissions and is resilient to climate change; Demand a watershed free of environmental injustices; Maintain a watershed in which the natural hydrology is protected, restored, and enhanced; Instill a water ethic within institutions and people that will make efficient use of water a California way of life Thresholds of Significance For the purposes of this EIR, impacts on drainage, flooding, groundwater recharge, and water quality would be considered significant if the Goals, Policies, and Actions of the General Plan Update would result in any of the following: Substantially increase the rate or amount of surface runoff in a manner that would result in flooding on- or off-site, or create or contribute runoff water that would exceed the capacity of existing or planned stormwater drainage systems to provide the designed level of flood control 5.8-7

8 Substantially alter the existing drainage pattern of the site or area in a manner that would generate substantial additional sources of polluted runoff, substantially degrade water quality, or violate any water quality standards or WDR Result in a net deficit in aquifer volume or a lowering of the local groundwater table level at the projects site such that existing uses in the groundwater area of influence that rely on groundwater wells could not be reasonably supported Expose people or structures to a significant risk of loss, injury or death involving as a result of the failure of a levee or dam Environmental Impacts Would the project substantially increase the rate or amount of surface runoff in a manner that would result in flooding on- or off-site, or create or contribute runoff water that would exceed the capacity of existing or planned stormwater drainage systems to provide the designed level of flood control? Implementation of the General Plan Update could result in an additional 23,492 households and an additional 40,599 employees within the planning area that will entail construction of projects with impervious surfaces. The focus for growth in the General Plan Update is in the Downtown Core of the City and Livable Corridors (as described in Chapter 14 - Downtown Area Plan of the General Plan Update) which is currently developed and contains stormwater drainage facilities. The construction of structures and facilities with impervious surfaces in areas where there are currently no impervious surfaces, potentially increasing the rate of stormwater runoff compared to existing conditions. The amount and rate of potential increase in runoff would depend upon site topography, existing infiltration characteristics, distance from receiving drainage, and any planned or designed detention. The City has adopted existing regulations and policies that minimize on- and off-site flooding which can alter drainage patterns or stream course and cause erosion and sedimentation impacts. The floodway and floodplain districts regulations contained in the Municipal Code are specifically designed to prevent and regulate development in flood-prone areas. MS4s are issued permits based on the size of the municipality. MS4 permit requirements include the reduction of pollutant discharges to the MEP and protection of water quality. Requirements also include identification of major outfalls and pollutant loads and control of discharges from new development and redevelopment. Future projects undertaken over the planning horizon of the General Plan Update may cause changes in drainage patterns, increased imperviousness, and other effects that could potentially alter local hydrology that could cause or contribute to local flooding and exceedance of local drainage system capacity. However, the City of Fontana is subject to the NPDES permitting process under its MS4 codified as Title 14 (Storm Drains and Flood Management) of the Municipal Code. Implementation of the requirements of the MS4 permit and other regulations mentioned in this section would ensure that the volume and rate of stormwater runoff from future development would not exceed local drainage volume and flow requirements and would prevent 5.8-8

9 downstream flooding. This would reduce potential stormwater runoff and drainage impacts to less-than-significant levels. The General Plan Update includes Goals, Policies, and Actions that would further reduce impacts to hydrologic resources. Applicable Goals, Policies, and Actions include the following: Table Applicable Goals, Policies, and Actions Goals & Policies Chapter 10 Infrastructure and Green Systems Element Action Goal 1: Fontana collaborates with public and private agencies for an integrated and sustainable water resource management program. Support initiatives to provide a long-term supply of the right water for the right use by working with regional providers and the One Water One Watershed Plan. A. Be active in regional water-resource planning and implementation. B. Continue to participate in the Santa Ana Watershed Authority planning and implementation efforts. C. Advocate with the IEUA for more recycled water and groundwater recharge. D. Use an integrated water- management approach when working on land use and zoning changes. E. Incorporate integrated water- management best practices into land use and zoning initiatives, including water conservation and recycling as well as permeability and infiltration. Goal 6: Fontana has a stormwater-drainage system that is environmentally and economically sustainable and compatible with regional One Water One Watershed standards. Continue to implement the Water Quality Management Plan for stormwater management that incorporates Low-impact and greeninfrastructure standards. Promote natural drainage approaches (green infrastructure) and other alternative nonstructural and structural best practices to manage and treat stormwater. A. Continue to maintain traditional stormwater infrastructure as needed, while developing methods to promote ultimate infiltration of the water. B. Explore options for infiltration of water from traditional stormwater facilities. C. Promote simple green-infrastructure retrofits for existing buildings and properties, such as rain barrels. D. Revise development standards to reflect low-impact and green- infrastructure stormwater-management requirements in order to meet or exceed watershed goals. I. Use street parkways and medians to treat and infiltrate runoff in transportation projects, new development, and redevelopment. J. Use permeable surfaces to promote infiltration wherever feasible

10 Would the project substantially alter the existing drainage pattern of the site or area in a manner that would generate substantial additional sources of polluted runoff, substantially degrade water quality, or violate any water quality standards or WDR? The General Plan Update does not consider or analyze specific development projects; therefore, the actual potential for future construction sites or developments associated with the General Plan Update Goals, Policies, and Actions are unknown. The City of Fontana is subject to the NPDES permitting process under its MS4 codified as Title 14 (Storm Drains and Floodplain Management) of the Municipal Code. Although urban runoff is considered a nonpoint of source of pollution, municipal storm drain outlets are readily defined and can be individually monitored, thereby defining them as point sources for the purposes of administering NPDES permits, even though the origin of the source is diffuse. NPDES regulations applicable to the Planning Area are designed to reduce non-point-source pollutant loading through implementation of BMPs and other control measures that minimize or eliminate pollutants from urban runoff, thereby protecting downstream water resources. The City of Fontana implements NPDES provisions through the requirements of its MS4 permit, which is applicable to all portions of the City. BMPs implemented to address residential pollutant sources generally revolve around educational programs. Commercial and industrial development is subject to annual inspections to ensure implementation of BMPs and educational programs. Implementation of the requirements of the MS4 permit and other regulations mentioned in this section would ensure that the volume and rate of stormwater runoff from future development would not exceed local drainage volume and flow requirements and would prevent downstream flooding. This would reduce potential stormwater runoff and drainage impacts to less-than-significant levels. As noted above, the General Plan Update includes Goals, Policies, and Actions that would further reduce impacts to hydrologic resources as noted above. Would the project result in a net deficit in aquifer volume or a lowering of the local groundwater table level at the projects site such that existing uses in the groundwater area of influence that rely on groundwater wells could not be reasonably supported? Future development within the Planning Area would require additional water services that would come from local groundwater sources. Future development may also impact groundwater recharge by increasing impervious surfaces that could hinder percolation of drainage into subsurface aquifers. Future development could also impact groundwater recharge if existing spreading grounds are altered (e.g., developed upon) without construction of replacement facilities. Additionally, drainage may be directed away from its natural source where it may be deposited in other water bodies. Impacts associated with depleted groundwater supplies included increased demand on out-of-region water resources and the energy and cost associated with the importing of other resources. The lowering of aquifer and groundwater levels in an area can cause existing wells and pumps to become non-functional if they are not designed to extract water below certain depths

11 The General Plan Update does not consider or analyze specific development projects; therefore, the actual potential for future construction sites or developments associated with the General Plan Update Goals, Policies, and Actions are unknown. Furthermore, the Santa Ana River Watershed, including the Santa Ana Groundwater Basin, are managed by an adjudication and subject to the terms of the 1969 Stipulated Agreement managed by the SAR Watermaster. The Santa Ana River Watershed includes programs for the long-term management of area groundwater basins. The primary means of ensuring long-term groundwater level maintenance includes careful monitoring to ensure groundwater levels are managed within a safe basin operating range and implementation of water conservation programs. The General Plan Update supports water conservation through use of natural and drought-tolerant vegetation and through water recycling. Additionally, water conservation programs of the General Plan Update are designed to ensure groundwater resources are recharged both through natural and assisted means. Water conservation helps to maintain groundwater levels by reducing the need to extract from them. As a result, the potential for impacts to groundwater levels within the region is less than significant. As noted above, the General Plan Update includes Goals, Policies, and Actions that would further reduce impacts to hydrologic resources. Would the project expose people or structures to a significant risk of loss, injury or death involving as a result of the failure of a levee or dam? The General Plan Update does not consider or analyze specific development projects; therefore, the actual potential for future construction sites or developments associated with the General Plan Update Goals, Policies, and Actions are unknown. However, some future development could result in the construction of certain structures and infrastructure in the SAR floodplain that would be exposed to flood conditions from the 100-year flood event as mapped by the FEMA in the FIRM for the area. Furthermore, the City of Fontana is not located in a mapped dam inundation area. There are areas shown on the FIRM as having minimal risk from the failure or overtopping of a levee or flood control channel. These are on the Hawker Crawford Channel, the Etiwanda/San Sevaine Channel, San Sevaine Channel, and West Fontana Channel. These are either delineated as Shaded Zone X (i.e., areas protected from flooding by a levee), Zone X (i.e., 500- year floodplain), Zone A (i.e., no base flood elevations determined), or Zone AO (i.e., depth 1 foot) on the FIRM. As a community that participates in the NFIP, the City has specific ordinances that require permits for such development, and the conditions contained in these permits are designed to reduce the potential risk and impacts of flooding. Therefore, impacts from flooding due to a 100- year event or from the failure of a levee or dam would be less than significant. As noted above, the General Plan Update includes Goals, Policies, and Actions that would further reduce impacts to hydrologic resources

12 5.8.5 Mitigation Measures No mitigation measures are required that would further reduce the identified less than significant impacts References Federal Emergency Management Agency Effective Flood Insurance Rate Map (FIRM) for Fontana, CA. National Water Research Institute Report of the Scientific Advisory Panel, Orange County Water District s Santa Ana River Water Quality and Health Study. August Orange County Water District Santa Ana River Water Quality and Health Study Final Report. Santa Ana Regional Water Quality Control Board Water Quality Control Plan Santa Ana Region (#8). Santa Ana Regional Water Quality Control Board Amendments to the Santa Ana Region (#8) Water Quality Control Plan Santa Ana River Watermaster Thirty-Fourth Annual Report of the Santa Ana River Watermaster. Santa Ana Water Project Authority One Water One Watershed Plan State Water Resources Control Board IV. Groundwater Quality Assessment. California s 305(b) Report State Water Resources Control Board. Appendix D: Attachment to Resolution No. R Amendment to the Santa Ana Region Basin Plan. Swrcba.gov/rwqcb8/pdf/tmdl/appendix.pdf