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HomeMy WebLinkAbout03-Council Office --- ...-, c o C I T Y 0 F SAN B ERN A R DIN 0 INTEROFFICE MEMORANDUM 85l2-207 RECEi\iF'r v:: i:R! '85 DEe -3 P3:13 TO: Shauna Clark, City Clerk FROM: Council Office SUBJECT: Agenda Item DATE: December 3, 1985 (6547) COPIES: Mayor and City Administrator ------------------------------------------------------------- Please place the following item on the Council agenda for Thursday, December 5, 1985: Briefing on Water Issues by Mr. Rowe and Mr. Lightfoot, East Valley Water District. This request was coordinated and consented to by Councilman Marks. ~-~) ~\\~-s:- PHILI A. ARVIZc6 Executive Assistant to the Council PAA: jv =) J 1""" f . v;1~y C Water District o ~M~ :> .- East 1155 Del Rosa Avenue P.O. Box 3427 San Bernardino. California 92413 (714) 889-9501 05 U1 December 1, 19~ ,-." ',"J ". m ("") rTl .,..., _J President Henry Van Mouwerik S.B. Valley Municipal Water District P.o. Box 5906 San Bernardino, CA. 92412-5906 I ..,. .- . -0 -J .t.:.. ..,. n :-',~~ Dear President Van Mouwerik, The Board of Directors for the East Valley Water District is deeply concerned by the action taken by the San Bernardino Valley Municipal Water District in adopting a Notice of Exemption for it's proposed "Super Well" project. The manner in which this significant and controversial project was brought forward precluded any affected party from commenting on the mitigation of near surface groundwater in the southwestern portion of the San Bernardino Basin. In reviewing the proceedings at which the Notice of Exemption was adopted by your Board, the East Valley Water District Board of Directors was distressed to find that no scientific or engineering data was presented to support the need for exemption from the California Environmental Quality Act requirements. While there has been much speculation and many partial studies of the liquifaction potential in the area impacted by near surface waters, there appears to be no single study which assesses the potential hazard and method by which it may be addressed. In point of fact, there remains some question as to_the exact area which may be prone to liquifaction during a seismic event. ""- To better understand the current body of published data, the East Valley Water District retained the URS Company to conduct a literature search relating to the broad range of seismic issues present in the San Bernardino Basin Area. I have attached a partial listing of the material reviewed for your information. The net result of the literature search is that there have been no published reports which are specifically designed to study the magnitude or areal extent of the potential hazard. In lieu of a rational scientific method, there seems to be a single minded approach which would lower near surface water levels without any effort to understand the nature or complexity of the problem. I would point out that near surface water is only one of four criteria necessary for liquifaction to take place. To undertake the drilling of high capacity dewatering wells without specific knowledge as to whether they will be effective in lowering near surface water levels in those areas which may be at risk would appear premature. The issues associated with any large extraction project in the lower basin are far reaching and Glenn R. Lightfoot President Steyen E. Beightler Vice-President Philip A. Disch Director Dennis L. Johnson Director Gerald W. SlOOpS. Director Larry W. Rowe General Manager. Secretory Grenda O. Jay Auditor-TreosurH' .- ~ . 'East' V~U~y Water Oistric9 ,'....''''"' "-0../ J President Van Mouwerik SB Valley Municipal Water District Page 2 affect many entities, both public and private. The impacts on near surface and deep aquifer water quality cries out for assessment and public review prior to the construction of any project. It is our understanding for example that, based on a report prepared for the City of San Bernardino on probable pollutant flow paths, the "Super Well" proposed in the vicinity of Mill Street and the Warm Creek Flood Channel may lie in the path of the TCE plume presently moving southward from north San Bernardino. If our understanding is correct, what impact on pollutant migration will the proposed "Super Wells" have? Given the complexity of the seismic, environmental and institutional questions present, it would seem that any hastily implemented program to mitigate near surface groundwater has the potential for creating adverse impacts which could conceivably transcend the immediate problem. It is interesting to note that your District, Chino Basin Municipal Water District, and Orange County Water District have taken the position that a similar cooperative project proposed by the City of Riverside and Western Municipal Water District should be subject to the California Environmental Quality Act. Why is their project subject to CEQA and yours not? Additionally, the "201 Wastewater Facilities Planning Study" prepared by your agency indicates that the preferred alternative for mitigating tertiary treatment requirements is to drill a network of extraction wells in the lower basin and thus reduce river flows. If the solution to near surface groundwater and tertiary treatment requirements is pumping the lower basin, is it not time to bring all pumping proposals forward at one time so that their benefits and disbenefits may be heard in a public forum by those on whose behalf the projects are being initiated? " There are solutions currently at hand capability of moving quantities of water far in being proposed in the Notice of Exemption. which have the excess of what is The Directors of the East Valley Water District have consistently supported efforts to mitigate the adverse impacts of high groundwater in the southwestern portion of the San Bernardino Basin. To date, the cooperative efforts of the city of San Bernardino, city of Riverside, East Valley Water District, San Bernardino Valley Water Conservation District, Western Municipal Water District, Orange County Water District and the San Bernardino Valley Municipal Water District have resulted in the lowering of near surface water levels over much of the area impacted by high groundwater. Joint efforts utilizing existing production facilities represents, in our opinion, the most expeditious method for controlling near surface water. It would , ;-- 6 'East V~r;y Water Distri~ o :) President Van Mouwerik SB Valley Municipal Water District Page 3 seem that if the goal is to reduce near surface water to a prudent level, utilization of the idle facilities within the impacted area belonging to the cities of San Bernardino, Riverside, the East Valley Water District and others would represent immediate available capacity which has proven effective in lowering the near surface waters. The Directors of the East Valley Water District requests that the Directors for the San Bernardino Valley Municipal Water District rescind their recent adoption of the Notice of Exemption for their proposed "Super Well" project until such time as the appropriate environmental analysis can be completed and provided for public review. In the interim, the existing idle winter capacities within the impacted area remains the most effective method available to mitigate the near surface waters. r;:: ?=~~ Glenn R. Lightfoot President grl/s 0- .~ " " . -u,' .'.... ,( ~. , ../ (c 0 ( :) San Bernardino Valley Municipal Water District 1350 SOUTH "E" STREET, P,O, BOX 5906 - SAN BERNARDINO. CALIFORNIA 92412,5906, (714) 824-2200 (714) 889.{)+J3 July 26, 1985 '~f:;oc "'" ~J',;~ JUL . 0 29 1985 W,Af.w,o. Mr. Howard A. Hicks General Manager Western Municipal Water District 6377 Riverside Avenue Riverside, CA 92516 Subject: Initial Study California Street Pumping Plant Dear Howard: We have reviewed your initial study on the subject project and find that it only addresses the specific impacts at your proposed booster pumping station site, and not the impacts of the project on the Bunker Hill Groundwater Basin or the city of Riverside transmission system. We believe these unaddressed impacts are the essence of the environmental analysis for this project. We, therefore, consider your initial study incomplete and request you analyze the following key impacts and circulate your response prior to making a determination: ,> 1. Analyze the potential increased rate of existing known contaminents in the Bunker water Basin due to increased pumping groundwater lowering. migration of Hill Ground- and resultant 2. and operational effect on existing in the Bunker Hill Basin due to We strongly suggest you make your study to all producers in the Determine the economic wells and producers increased pumping. available copies of Bunker Hill Basin. 3. Describe how the export of water from the Basin will impact the existing Judgements and the so-called Metro- politan \Vater District of Southern California "Amendment 12" problem. \Ve suggest you send a copy of your Initial study to the Orange County Water District for their review. 4. Discuss the hydro-geologic and geothermal effects of removal of groundwater from the groundwater basin increased rates and quantities_ the at 5. Evaluate alternatives to the project, including the value of the water pumped. '. Dlrectors and Offtc~rs WilLIAM KAl"OS^ GEORGE A. ACUILAR C. PATRICI-i: MILLIGAN HENRY H. VAN MouwERrK MARGARETe. WRtGHT G. LOUIS fl.ETCHER. Di"i.ion , Di..j.ion II Oi,;j,iof\ III Divhion IV Divi.ion V ec.nlU~1 ~hnaler ~<f' .,- ( c o ( :) " Mr. Howard A. Hicks Page 2 July 26, 1.985 We look forward to reviewing a revised document .which addresses our concerns. sincerely, ~ ~ a-/h~ G. Louis Fletcher General Manager GLF /j g ~cc: Neil Cline, Orange County Water District ,- r c o :> EAST VALLEY WATER DISTRICT High Groundwater and Related Liquefaction Potential in the San Bernardino Valley -- An Annotated Bibliography Submitted by URS Corporation San Bernardino, CA November 26, 1985 - ( EYWD/EVWD1-1 c :) J Artificial Recharge in the Bunker Hill-San Timoteo Area, 1959-1977, Caouette, San Bernardino Municipal Water District, 1978. This report does not specifically reference liquefaction, but indicates the amount of artificial recharge resulting from San Bernardino Valley Municipal Water District practices. These data are relevant to liquefaction in the San Bernardino Valley, since liquefaction potential is increased with rising groundwater levels and the rising groundwater levels in the San Bernardino Valley have been attributed to extensive artificial recharge and wetter than normal winters (Carson and Matti, 1982). This report is a survey of past and present facilities utilized for artificial recharge (water spreading) within the San Bernardino Valley Municipal Water District. Tables summarizing recharge amounts are provided along with maps that identify recharge points. Overall, the amount of recharge in the San Bernardino Valley Municipal Water District is summarized below: Water year 72-73 73-74 74-75 75-76 76-77 Recharge in Acre-Feet 21,741 26,644 5,453 19,360 17,512 average 13,342 acre-feet/year This document is provided in its entirety. urvey, This map was prepared as an initial step in an ongoing U.S. Geological Survey liquefaction-potential study. It is accompanied by 30 pages of text and an 18 page appendix. The map identifies 20 areas in the Upper Santa Ana River Basin where groundwater was shallower than 50 feet below ground surface at least once between September 1973 and September 1979. Data for the study were obtained from the Cal ifornia Department of Water Resources well records. Shallow groundwater regions identified are located in the following general areas: 1. Cl a remont 2. South of Pomona 3. Southwest of La Verne 4. San Antonio Wash 5. Upland 6. San Antonio Canyon Fan 7. Lytle Creek Canyon 8. Lytle Creek Fan 9. Cajon Wash 10. Southwest of the San Bernardino Mountains 11. Santa Ana Floodplain 12. Mi 11 Creek 13. Mentone 14. East of Yucaipa 15. San Timoteo Canyon 16. Reche Canyon 17. Muscoy 18. San Bernardino 19. Greater Santa Ana River 20. Ri versi de / r ~VWD/EVI~Dl-2 _. o J o With respect to liquefaction, the accompanying text points out that lique- faction-induced ground failure occurs in areas underlain by loose, granular, cohesionless, unconsolidated sediment that is saturated by water. However, liquefaction potential decreases as the thickness of overburden increases, and liquefaction rarely occurs at depths greater than 50 feet below land surface. The mapped areas of shallow groundwater are therefore likely to contain some water-saturated sedimentary materials that may be susceptible to liquefaction in an earthquake of sufficient magnitude and duration. The text references the fact that groundwater levels in the region historic- ally were high (during the late nineteenth century), and present-day ground- water levels now reflect those earlier conditions. The decrease in water levels is attributed to irrigation, industrial, municipal, and domestic uses. The recent increase in groundwater levels is thought to be due to wetter than normal winters (1978-1979) and extensive artificial recharge of regional groundwater basins. The only area which could be substantiated as having perched water was Riverside, however, several other areas are suspected to have perched water tables as well. This report in included in its entirety. Develo ment and Use of a Mathematical Model of the San Bernardino Valle Groun water Basln, Ca Hornia, Open Fi e Report 80-576, Har t and Hutchinson, U.S. Geological Survey and San Bernardino Valley Municipal Water District, 1980. , This report does not discuss liquefaction, but predicts the expected rise in groundwater levels through the year 2000. Since high groundwater (shallower than 50 feet below ground surface) is the major factor controlling liquefac- tion in this area (Matti et al., 1985); this report should prove useful for predicting future liquefaction hazards. Water level predictions are based on a computer model for the San Bernardino Valley area. The model includes the combined effects of natural recharge, artificial recharge of imported water, and groundwater pumping. Six hydro- logic conditions were modeled for the basin. Artificial recharge of one-half entitl ement and full entitl ement from the Ca 1 Horni a Aqueduct were coupl ed with low, average, and high natural recharge to the basin. The greatest water level increase was predicted to occur along the San Bernardino Mountain front. The model also predicted that water could rise to the land surface in the formerly swampy areas (between Warm Creek and the Santa Ana River adjacent to the San Jacinto fault) by 1983 under maximum recharge and average pumping conditions. The report includes maps of the predicted water level increases between 1975 and 2000 under both maximum and minimum recharge conditions. This document is provided in its entirety. 'I~ ~, EVWD/EVWDl-3 o o J EarthAuake and Geologic Hazards Conference, State of California Resources gency, 1964. This document summarizes a selected presentation dealing with liquefaction hazards associated with recent earthquakes. Examples of the types of magni- tudes of damage due to liquefaction are discussed based on recent earthquakes in California and other areas. This document is included in its entirety. Earthquake Hazards in the Los Angeles Region, Tinsley, Youd, Perkins, and Chen, U.S. Geological Survey, 1985. This is a preliminary report, scheduled to be officially published during mid-December 1985. The report provides a thorough discussion on the subject of lique- facti on and i ncl udes severa 1 1 i quefacti on potenti a 1 maps for the San Bernardino Valley area. The maps delineate regions in which any cohesionless granular layers are estimated to have very high, moderate, or lower suscepti- bility to liquefaction. The report states that an earthquake sufficient to induce liquefaction in the Los Angeles region (including San Bernardino Valley) is anticipated to occur within the next 30 to 50 years. The chapter on liquefaction potential is provided in its entirety. Earthquake Planning Scenario for a Magnitude 8.3 Earthquake on the San Andreas Fault in Southern California, Special Publications 60, Davis, Bennett, Borchardt, Kahle, Rice and Silva, California Department of Conservation, Division of Mines and Geology, 1982. This document provides information on the effects of, and mitigative planning strategies, for an earthquake of 8.3 magnitude on the San Andreas Fault. Liquefaction potential is mapped for many areas, including the San Bernardino Valley on pages 36 and 37. Areas of high and moderate potential are shown. The report states that much of the San Bernardino and Riverside areas are subjected to intensity 8 shaking because of the alluvial substrate. In the event that fault rupture extends further southeast than the scenario assumes, the entire San Bernardino area can be expected to experience shaking of intensity 9.0. The report also states that in areas with high groundwater and granular materials near San Bernardino and along the Santa Ana River, intensity 9.0 shaking will occur even if the fault rupture does not extend further southeast. This document is provided in its entirety. Feasibility Study of Pum~ing Groundwater from the San Bernardino Pressure Zone Into the State Aque uct, Metcalf & Eddy, 1983. This report does not reference liquefaction but outlines the feasibility of lowering groundwater tables by pumping water from the San Bernardino pressure zone into the California Aqueduct. Since the controlling factor for lique- -r _ E.lJWD/EVWDl-4 o C) J faction potential in the San Bernardino Valley is depth to groundwater (Matti et a1., 1985), alternatives which would lower the groundwater and consequently the liquefaction potential should prove useful. This report studies four existing water distribution facilities in the San Bernardino Valley Municipal Water District, and provides cost estimates for pumping groundwater from them. The results of the study show that if the State Project power rate is available for the booster pumping facilities, then all alternatives considered have a total cost per acre foot slightly less than State Project Water. This report is provided in its entirety. / Geologic Hazards in Southwestern San Bernardino County, California Special Report 113, L. Fife, U.S. Geological Survey, California Division of Mines and Geology, County of San Bernardino Environmental Improvement Agency and County of San Bernardino Planning Department, 1976. This is a 39 page document with 33 separate illustrations. Two maps of interest with respect to liquefaction are as follows: 1. Surface waters and marshes in the late 1800s and generalized depth to groundwater in the upper Santa Ana Valley. '. 2. Generalized map showing thickness of freshwater-bearing alluvium, upper Santa Ana Valley, and maximum credible rock acceleration from earthquakes in the vicinity of southwestern San Bernardino County. Liquefaction is discussed briefly in the text. It is noted that the potential for liquefaction exists in all a11uviated areas within the Upper Santa Ana Valley. The greatest potential exists where there are shallow perched water tables. Soil types within the San Bernardino Valley area are largely sand and silt. They generally have a high potential for liquefaction in areas of groundwater of less than 50 feet. These areas correspond to the old lowlands or drainge areas of surface waters and swamps of the late 1800s. Ground failure hazards associated with liquefaction are defined. These are (1) flow landslides (occuring on moderate to steeply dipping slopes), (2) lateral spreading landslides (occuring on gently dipping to nearly hori- zontal slopes), and (3) quick condition failure (occuring on horizontal, saturated silts/sands where drainage is confined to the immediate area of liquefaction). During liquefaction, buildings and cars often settle into the ground while gaso1 ine storage tanks and septic tanks often float to the surface. In short, the soils behave as a liquid and will not support struc- tu res. This report and accompanying maps are available from either the University of California at Riverside (UCR) Physical Sciences Library or the City of San Bernardino Central Library. Selected sections are provided. .~'I- tVWD/EVWDl-5 c o :) Geologic and Hydrologic Features of the San Bernardino Area California with Special Reference to Underflow Across the San Jacinto Fault, Geological Water Supply Paper 1419, Dutcher and Garrett, U.S. Geological Survey and San Bernardino County Flood Control District, 1963. Specific information relating to precipitation, groundwater hydrology, and geology for a large portion of San Bernardino County is given in 111 pages of text and 19 figures. The publication date of the document renders it most useful for historical water level information. It is available from the UCR General Library. " Ground Water Monitoring Wells, Various Locations within San Bernardino, California; Review of Data, Report Number 2609, Roger S. Shervington, P.E., John R. Byerly, Inc., 1982. The purpose of this report was to provide the City of San Bernardino Municipal Water Department with geotechnical information to aid in liquefaction poten- tial evaluation. Monitoring wells and soil samples were accomplished and evaluated at seven shallow groundwater sites within the City of San Bernardino. Borings were shallow (less than 55 feet) and groundwater was encountered at only two of the seven sites. These sites were located at the terminus of Central Avenue and directly in front of the San Bernardino City Hall. Groundwater was encountered at 31.5 and 32.5 feet, repectively. Liquefaction potential was determined to be very high at these sites. Lique- faction potential at two addtional sites was determined to be possible if water levels rose. At the remainder of the sites, liquefaction was deter- mined to be unlikely. This report is provided in its entirety. Failure, Geolo ical Surve Circular This paper provides a comprehensive overview of what liquefaction it relates to ground failure. Methods for evaluating liquefaction failure potential are also briefly examined. is and how and ground- This paper is provided in its entirety. Pending Open-File Report, Matti, U.S. Geological Survey, 1986. This report is scheduled to be published in January or February of 1986, and is a comprehensive study of liquifaction within the San Bernardino Valley. Information was gathered from all available sources (federal, state, county, city, and local) for examination and incorporation where accurate and applic- able. Liquefaction potentials are defined for groundwater elevations. Findings include that liquefaction will most probably occur in areas of 10-foot surface to groundwater depths, and that areas of 10 to 30 feet ground- water levels have a moderate to high risk of experiencing liquefaction. Groundwater is identified as the major controlling factor of liquefaction potenti a 1. . ,. , \ ',- .~ . EVWD/EVWDI-6 c o -, '-. ,J This report will be available through the U.S. Geological Survey, Pricing information will be given by the Public Inquiries Office at (213) 894-2850. The document may be ordered from: U.S. Geological Survey P.O. Box 25425 Federa 1 Center Denver, CO 80225 Rising Groundwater in Downtown San Bernardino, Stetson Engineering, Inc., 1983. This report states that liquefaction potential in the City of San Bernardino is high. Lowering groundwater is given as one way to reduce the effect of liquefaction in a substantial earthquake. Water levels of 15 to 30 feet below ground surface are stated to be considered safe. An increase of production from the pressure zone of about 25,000 acre-feet per year is about 4 years according to this report. Detailed accounts of the hydrology and geology of the Bunker Hill Basin are provided along with several potential solutions to mitigate rising groundwater problems. This report is provided in its entirety.