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HomeMy WebLinkAbout19594 ORD - 12/30/1986AN ORDINANCE AUTHORIZING THE EXECUTION OF AN AGREEMENT WITH THE UNITED STATES GEOLOGICAL SURVEY FOR A SEDIMENTATION STUDY OF LAKE CORPUS CHRISTI; AND DECLARING AN EMERGENCY. BE IT ORDAINED BY THE CITY COUNCIL OF THE CITY OF CORPUS CHRISTI, TEXAS: SECTION 1. That the City Manager is hereby authorized to execute an agreement with the United States Geological Survey, Department of the Interior, for a sedimentation study of Lake Corpus Christi, with the City's contribution to be $145,307.40, and with other material provisions to be substantially as set forth in the attached Exhibit "A." SECTION 2. That upon written request of the Mayor or five Council members, copy attached, to find and declare an emergency due to the need of executing the abovementioned agreement at the earliest practicable date, such finding of an emergency is made and declared requiring suspension of the Charter rule as to consideration and voting upon ordinances or resolutions at three regular meetings so that this ordinance is passed and shall talo effect upon fir_ first reading as an emergency measure this the 30 day of �Gein19 0 ATTEST: —7dw'r-9 City Secretary MAYOR APPROVED: a O DAY OF fi2c c9...d.vr-, 19 8--C HAL GEORGE, CITY ATTORNEY By Ass" int City Attorney 01P.01O.01 THE CI Y OF CORPUS CHRISTI, TEXAS 19594 MICROFILMED REQUEST FOR PROPOSAL TO CONDUCT SEDIMENTATION SURVEY LAKE CORPUS CHRISTI PROPOSE: To survey Lake Corpus Christi to determine the extent to which sedimetation has reduced water storage capacity, to produce area/capacity curves, and provide an appropriate report on the findings. SCOPE: A. Conduct a field survey, of the entire lake•and Nueces River to the northern point where Gildon Creek enters the Nueces River, by continuous acoustical profiling, with boat location monitored by a two or three -station radio location -finding apparatus. B. Produce approximately 150 miles of cross-sections and profiles to insure adequate coverage of the entire area. Make a permanent record of the soundings and profiles and preserve for future reference. C. Update the Base Map prepared by McCaughan & Etheridge in 1972, to show the current lake outline at elevation 94.0' M.S.L. and show the current bottom contours in relation to the 1972 contours. D. Research the records of the Texas Water Development Board and other agencies on sediment transport records since 1972 to see if the findings correlate to the survey, and, if possible from the available data make a prediction on the rate of sedimentation in the future. E. By calculations and actual field data, produce area -capacity curves at 0.5' intervals to show current conditions as of the date of the survey, down to elevation 60.0' M.S.L. F. If possible, from current data and river conditions permit, locate the point on the Nueces River where the bottom of the river intersects the 94.0' M.S.L. plane, which is the northern- most boundary of Lake Corpus Christi as recognized by the State of Texas. The location should be marked with a permanent monument. CONDITIONS: It is desired that the actual field survey be conducted when the lake is as near elevation 94.0' M.S.L. as possible. However, if it becomes apparent that these conditions might not exist in the foreseeable future then the USGS will consult with the City and recommend a course of action. DATA: All current lake data, history and the 1972 Sedimentation Survey conducted by McCaughan & Etheridge will be provided to the USGS to assist in conducting the survey. 1 PROPOSAL: It is assumed that the USGS will provide all personnel, boats and equipment to complete the proposed survey on a reimbursable basis, with only incidental assistance provided by the City. It is requested that USGS provide an estimate of the cost of the survey on that basis. 2 Department of the Interior U.S. Geological Survey Joint Funding Agreement FOR THIS AGREEMENT is entered into as of the day of , 1986, by the CITY OF CORPUS CHRISTI, STATE OF TEXAS, party of the first part, and the GEOLOGICAL SURVEY, UNITED STATES DEPARTMENT OF THE INTERIOR, party of the second part. 1. The parties hereto agree that subject to the availability of appropriations and in accordance with their respective authorities there shall be maintained in cooperation in a Sedimentation Survey of Lake Corpus Christi, State of Texas, hereinafter called the program. 2. The following amounts shall be contributed to cover all of the cost of the necessary field and office work directly related to this program, but excluding any general administrative or accounting work in the office of either party. The field and office work and costs found in the attached Work and Cost Statements, which is attached hereto and executed by the parties to this agreement, are hereby incorporated in this contract and made a part hereof. (a) From city of Corpus Christi $145,307.40 by the party of the first part during the period Oct. 15, 1986 to July 31, 1987. (b) $29,181.00 by the party of the second part during the period Oct. 15, 1986 to March 31, 1987. (c) Additional amounts by each party during the above period or succeeding periods as may be determined by mutual agreement and set forth in an exchange of letters between the parties. 3. Expenses incurred in the performance of this program may be paid by either party in conformity with the laws and regulations respectively governing each party, provided that so far as may be mutually agreeable all expenses shall be paid in the first instance by the party of the second part with appropriate reimbursement thereafter by the party of the first part. Payments to the party of the second part by the party of the first part will be made quarterly upon billing by the party of the second part or immediately upon signature. Each party shall furnish to the other party such statements or reports of expenditures as may be needed to satisfy fiscal requirements. 4. The field and office work pertaining to this program shall be under the direction of or subject to periodic review by an authorized representative of the party of the second part. 5. The areas to be included in the program shall be determined by mutual agreement between the parties hereto or their authorized representatives. The methods employed in the field and office shall be those adopted by the party of the second part to insure the required standards of accuracy subject to modification by mutual agreement. 1 6. During the progress of the work all operations of either party pertaining to this program shall be open to the inspection of the other party, and if the work is not being carried on in a mutually satisfactory manner, either party may terminate this agreement upon 60 days written notice to the other party. 7. The original records resulting from this program shall be deposited ultimately in the office of the party of the first part and become part of the records of that office. Copies shall be furnished to the party of the second part upon request. 8. The maps, records, or reports resulting from this program shall be made available to the public as promptly as possible. The maps, records or reports normally will be published by the party of the second part. However, the party of the first part reserves the right to publish the results of this program and, if already published by the party of the second part shall, upon request, be furnished by the party of the second part, at cost, impressions suitable for purposes of reproduction similar to that for which the original copy was prepared. The maps, records or reports published by either party shall contain a statement of the cooperative relations between the parties. GEOLOGICAL SURVEY UNITED STATES DEPARTMENT OF THE INTERIOR By ATTEST: CITY OF CORPUS CHRISTI By Armando Chapa Craig A. McDowell City Secretary City Manager APPROVED: DAY OF" , 19 HAT• GEORGE, CITY ATTORNEY By By Jimmy Bray James K. Lontos Assistant City Attorney Assistant City Manager 2 SEDIMENTATION SURVEY, LAKE CORPUS CHRISTI Work Statement Introduction Lake Corpus Christi is formed by the Wesley Seale Dam across the Nueces River in south Texas (fig. 1). Lake Corpus Christi is owned by the Lower Nueces River Water Supply District and is operated by the City of Corpus Christi. However, effective August 1, 1986, ownership of the lake and dam will be transferred to the City of Corpus Christi as a result of legislation passed by the Texas Senate and House of Representatives and signed by Governor White. Municipal and industrial water supplies for Corpus Christi and several smaller, adjacent cities of the Coastal Bend come principally from Lake Corpus Christi and, in lesser amounts, from water wells. From 1948 until 1982, drainage from the Nueces River and two tributaries, the Frio River and the Atascosa River, flowed into Lake Corpus Christi (fig. 1). In 1982, the Choke Canyon Dam was completed on the Frio River upstream from Lake Corpus Christi, thereby limiting the inflow from this tributary into the Nueces River. Water usage from the Choke Canyon Lake cannot begin until there has been a significant accumulation in the reservoir, which may be a few years in the future, depending on rainfall in the Frio River watershed. Water demands placed on Lake Corpus Christi are rapidly approaching its annual dependable yield. Also, the water storage capacity of Lake Corpus Christi is being reduced by sediment deposition. The amount of sediment deposited through 1972 is reported in a sedimentation study for the City of Corpus Christi by McCaughan and Etheridge Consulting Engineers, with the assistance of Southwest Research Institute. Similar information is needed for the period 1972-1985. Consequently, the Water Division, Department of Public Utilities, City of Corpus Christi, has requested the U.S. Geological Survey (USGS) to conduct a sedimentation survey of the lake. For the purpose of the USGS survey, the northern -most boundary of Lake Corpus Christi, which is also the boundary recognized by the State of Texas, is the point where the bottom of the Nueces River intersects the 94.0 foot M.S.L. (mean sea level) plane. Objectives The USGS proposes to conduct a sedimentation study of Lake Corpus Christi to accomplish a set of objectives outlined by the Water Division. These objectives are: (1) to determine the extent to which sedimentation has reduced water storage capacity; (2) to produce area/water capacity curves; and, (3) to provide a report on the results of the study. The field survey will be conducted when the water level in Lake Corpus Christi is as near to 94.0 feet M.S.L. as possible. However, if it becomes apparent that these conditions might not exist in the foreseeable future, then the USGS will consult with the appropriate Water Division officials to determine a course of action. 1 Figure 1. Map showing Lake Corpus Christi — Choke Canyon Lake areas and outline of aerial photography area. USGS Program The USGS program has six elements that are designed to achieve the objectives of the Water Division. 1. Lower Lake Corpus Christi sedimentation survey (a) A data collection survey will be made to lower Lake Corpus Christi from the Wesley Seale Dam to where Gildon Creek enters the Nueces River (fig. 1), or to the northernmost point navigable by the survey vessels.. (b) Navigation and surface locations for the survey will be provided by land survey, transit satellite receivers, GPS satellite receivers or radio frequency tri-lateration systems to insure complete coverage of the lake and river areas. (c) Laboratory and field calibration will be performed on all bathymetry and navigational equipment before data collection begins. Bar checks of the bathymetry equipment will be made on a daily basis to insure accurate depth measurements. (d) Bathymetric, navigational, and seismic profiling data will be collected along lines in a grid over the lake and river area, wherever possible. Survey lines will be spaced 1,000 feet apart on the lower part of the lake below a line from Indian Point to Sleepy Hollow (fig. 1). On the northern part of the lake, the data line spacing will be 2,000 feet apart. A minimum of 150 line miles of data will be collected. Shallow water depths and submerged vegetation may restrict boat movement and data collection in some areas. On the northern part of the lake, on the Nueces River, and in small coves, data will be collected on single or zig-zig lines because of limited space for maneuvering the survey vessels. (e) Subject to availability, the data acquisition and processing equipment to be used for the survey are: GPS satellite receivers Transit satellite receivers Maxiran positioning system Integrated data acquisition system - operating at 500 kHz, will provide accurate bathymetry measurements Datasonics subbottom profiler - operating at dual frequencies of 200 kHz and 12 kHz, should provide measurements on sediment fill EPC graphic recorder The Datasonics subbottom profiler and EPC Recorder will be mounted on a large boat that will also serve as an observation vessel for a smaller boat that will survey the very shallow and remote areas that would be inaccessible with the larger boat. 2. Upper Lake Corpus Christi - Nueces River survey Data will be collected on the Nueces River northward of the entrance of Gildon Creek, provided river currents and conditions permit, to determine the geographic location of the northern boundary of Lake Corpus Christi. Data 3 acquisition equipment and procedures, as previously described, will also be used in this phase, except that data will be collected in straight or zig-zag lines because of the narrow width of the river. 3. Data processing Datasonics subbottom soundings with 200 kHz and 12 kHz signals should provide measurements of the top of the sediment fill and the top of the pre -lake surface, respectively. These data soundings will be played back into seismic profiles over at least 150 line miles of coverage. Cross sections will also be constructed in the areas of the lake where there is significant sediment fill. The Datasonic soundings, seismic profiles and cross sections will be preserved for future references. 4. Maps (a) An aerial photographic survey will be flown by a contract company to provide photographic coverage of the area from below Wesley Seale Dam to the east end of Choke Canyon Lake (fig. 1). This area of photographic coverage will include the northern -most point of Lake Corpus Christi, where the bottom of the Nueces River intersects the 94.0 foot M.S.L. plane, which has never been mapped and the confluences of the Frio, Atascosa, and Nueces Rivers. Photographic mosaics of the lower and upper lake will be developed to serve as horizontal control in preparing maps and for use in establishing surface elevations. (b) The base map prepared by McCaughan & Etheridge in 1972 will be revised to show (a) the current lake outline at 94.0 feet M.S.L. and (b) the current bottom contours relative to the 1972 contours. (c) A map of Lake Corpus Christi will also be constructed showing, where possible, the areas and the amounts of sediment fill on the pre -lake surface. 5. Rate of sedimentation The amounts of suspended sediments transported into and out of Lake Corpus Christi (monthly, yearly, and 1972-1985 water years) will be computed or estimated from available data to determine or to estimate the sediment deposition in the reservoir. The rate of future sedimentation in Lake Corpus Christi will be predicted, if possible, on the bases of flow -duration data. Sediments transport records of the Texas Water Development Board and USGS will be compiled on five stations. These five stations are: (1) Frio River, Calliham Station; (2) Nueces River, Cotulla Station; (3) Atascosa River, Whitsett Station; (4) Nueces River, Three Rivers Station; and, (5) Nueces River, Mathis Station. These data will be analyzed and will be used to define historical relations between streamflow and suspended sediment transport. Future sedimentation rates will be estimated from monthly flow duration data. The median flow value for each month will be used to estimate monthly suspended sediment loads at appropriate locations. The resulting relations and regression equations 4 will be used to estimate monthly, annual, and 1972-1985 period suspended sediment transport into and out of Lake Corpus Christi. Sediment deposition in Lake Corpus Christi will be estimated by determining the difference between inflow and outflow suspended sediments. No attempt will be made to include those sediments which may be transported along the river bottom and which are commonly called "bedload sediments". Tables will be prepared summarizing monthly, annual, and 1972-1985 period of sediment transport into and from Lake Corpus Christi. Supporting figures, including curves showing relationships between streamflow and sediment concentration, will be plotted. An estimate of the future sedimentation rate will be prepared, based on regressions and on historical flow—duration data. 6. Area/water capacity curves Area/water capacity curves will be calculated at 1.0 foot intervals from actual field data to show the current conditions as of the date of the survey down to an elevation of 60.0 feet M.S.L. Final report The USGS will submit a final report to the Water Division within six months of completion of the data acquisition. The final report will include, but not be limited to, a narrative description of the data acquisition, an analysis of the sediment fill in Lake Corpus Christi, and curves, cross sections, profiles and other information acquired as part of this program. Water Division contributions The USGS program is based upon the provision that all current lake data, history, and the 1972 Sedimentation Study by McCaughan & Etheridge will be provided to the USGS to assist in the program. It is assumed that Water Division personnel assigned to the Wesley Seale Dam and to Lake Corpus Christi will be available to provide incidental assistance to the USGS. The Water Division will reimburse the USGS for expenses as set forth in the section entitled, Cost Statements, and in the Joint Funding Agreement. Cost Statements The USGS proposes to provide all personnel, boats, and data collection and processing equipment to complete the survey proposed herein. USGS expenses reimburseable by Water Division Data collection and processing Equipment rental Transit satellite receiver, 6,500.00 MX1502 Intergrated bathymetry system 4,500.00 Maxiran positioning system 3,900.00 Datasonic subbottom profiler 9,650.00 Portable electric generator 1,010.00 Boat rental 1,500.00 Shipping 1,000.00 Expendable supplies 500.00 5 $32,510.00 Computer and software, Hydris is processing MX1502 tape processing 2,250.00 1,700.00 5,500.00 6,000.00 13,768.00 4,500.00 2,250.00 Labor costs 32,018.00 Contract operator for MX1502 Contract operator for intergrated bathymetry and Golf III USGS - Electronic Technician John West 88 days Per diem 3 men, 30 days, $50/day MX1502 operator expenses 30 days, $50/day Sub -total 64,528.00 Assessment @ 5% 3,226.40 Total for data acquisition and processing $67,754.40 Data analysis and map and report preparation Contract aerial photography 15,000.00 Rates of sedimentation study 14,300.00 Salaries 36,960.00 Consultant 4,000.00 Harry Boryhill 80 hours @ $50.00/hr. Geophysicist 9,200.00 90 days Geologist 6,320.00 60 days Project Chief & Senior Geophysicist 16,060.00 Bell 80 days Typist 1,380.00 20 days Contract drafting — 352 hours @ $12.50/hr. 6,600.00 Miscellaneous expenses 1,000.00 Printing and reproduction 700.00 Expendable supplies 300.00 Subtotal Assessment — 5% Total for analysis, map and report preparation Total reimbursement by Water Division 6 73,860.00 3,693.00 $77,553.00 $145,307.40 USGS non—reimbursable expenses The USGS will contribute personnel, supplies, and equipment to the survey, at no cost to the Water Division, as follows: Personnel Electronic Technician, 30 days Per diem, 30 days @ $50/day Data collection and processing Equipment Recording fathometer Graphic recorder for subbottom profiler Magnetic tape recorder Radio communications Small boat and motor for Nueces River work Transit satellite receiver Pickup Preliminary survey, Nueces River Expendable supplies $4,641.00 1,500.00 2,250.00 1,800.00 3,000.00 1,800.00 1,000.00 10,300.00 1,000.00 $6,141.00 21,150.00 1,000.00 890.00 Total contribution by USGS $29,181.00 Key Personnel Professional Affiliations: Wifred Hasbrouck — Geophysicist Education: Colo. Sch. Mines, D. Sc. 1964 Experience: Seismic crustal studies development of magnetic methods, and geophysics and development of high resolution seismic techniques with emphasis on shear waves. Publications: Over 50 including recent summary of research on use of shear waves. John West - Electronic Technician Education: Penn State Univ. Electronics, 1964 - 1966 Univ. of Nev., Las Vegas Geology, 1968 — 1969 Government and industry electronic training schools and symposia. Experience: Geological and geophysical data acquisition in marine areas (Gulf of Mexico, offshore California, Alaska), on lakes (Lake Corpus Christi, Great Salt Lake), and rivers (Colorado River). Equipment used includes multichannel and high resolution analog and digital seismic recording and playback systems, side—scan sonar, precision and long range navigational systems, deep and shallow water bathymetric systems and others. 7 Publications: High resolution seismic data acquisition and seismic stratigraphy. Corpus Christi, Texas 3o day of mb r , 198go TO THE MEMBERS OF THE CITY COUNCIL Corpus Christi, Texas For the reasons set forth in the emergency clause of the foregoing ordinance or resolution, an emergency exists requiring suspension of the Charter rule as to consideration and voting upon ordinances or resolutions at three regular meetings; I/we, therefore, request that you suspend said Charter rule and pass this ordinance or resolution finally on the date it is introduced, or at the present meeting of the City Council. Respectfully, Respectfully, MAYOR 99.045.01 Council Members / AK 7w5 THE CI OF CORPUS CHRISTI, TEXAS The above ordinance was passed by the following vote: Luther Jones 041 Dr. Jack Best David Berlanga, Sr. Leo Guerrero Joe McComb Frank Mendez Bill Pruet Mary Pat Slavik Linda Strong Qi 19594