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HomeMy WebLinkAboutResolution - 2006-R0410 - Engineering Services Amendment Agreement - Black & Veatch Corporation - 08_24_2006Resolution No. 2006-RO410 August 24, 2006 Item No. 6.9 RESOLUTION BE IT RESOLVED BY THE CITY COUNCIL OF THE CITY OF LUBBOCK: THAT the Mayor of the City of Lubbock BE and is hereby authorized and directed to execute for and on behalf of the City of Lubbock, Amendment No. 2 to Agreement for Engineering Services by and between the City of Lubbock and Black & Veatch Corporation, and all related documents. Said Amendment No. 2 to Agreement for Engineering Services is attached hereto and incorporated in this Resolution as if fully set forth herein and shall be included in the minutes of the Council. Passed by the City Council this 24th day of August 2006. DAVID A. MILLER, MAYOR ATTEST: ..R becca G za, City Secretary APPROVED AS TO CONTENT: Thomas Adams, Deputy APPROVED AS TO FORM: Richard K. Casner, First Assistant Attorney ml/Richard/Resolutions/Black &Veatch.2nd Amend.res August 16, 2006 AMENDMENT NO. 2 TO AGREEMENT FOR ENGINEERING SERVICES Resolution No. 2006-RO410 August 24, 2006 Item No. 6.9 WHEREAS, the City of Lubbock, Texas (Owner) has duly executed and entered into that certain Agreement for Engineering Services (the "Original Agreement") dated the 131h day of January 2005 (and any amendments thereto and any work orders, work authorizations, purchase orders or documents of similar effect issued thereunder) with Black & Veatch Corporation (Engineer), providing for performing certain engineering services for the Water Resources Improvements (the Project); WHEREAS, pursuant to that certain Amendment No. 1 to Agreement for Engineering Services, Resolution No. 2005-R0563, dated on or about December 1, 2005 (the "First Amendment"), Owner and Engineer amended the Original Agreement in certain respects; WHEREAS, Owner and Engineer wish to amend Attachment A and B of the Original Agreement, in certain respects, as provided herein. NOW, THEREFORE, in consideration of the promises contained herein, Owner and Engineer agree this 24th day of August , 2006, as follows: ARTICLE 1—ATTACHMENT A That ATTACHMENT A OF THE ORIGINAL AGREEMENT, as amended by the First Amendment, shall be amended as follows: Attachment A Item B, PART 2 — DETAILED DESIGN of the Original Agreement, as amended by the First Amendment, is hereby supplemented with Amendment No. 2, Attachment A, which is attached hereto. ARTICLE 2—ATTACHMENT B That ATTACHMENT B, COMPENSATION, OF THE ORIGINAL AGREEMENT, as amended by the First Amendment, shall be amended as follows: Attachment B of the Original Agreement, as amended by the First Amendment, is hereby supplemented with Amendment No. 2, Attachment B, which is attached hereto. ARTICLE 3—AMENDMENT This Amendment, to the extent of any conflict with the Original Agreement, as amended by the First Amendment, shall supersede the terms and provisions of the Original Agreement, as amended by the First Amendment. However, it is the express intention of Owner and Engineer that this Amendment and the Original Agreement, as amended by the First Amendment, shall be completely integrated and be construed in harmony and congruity as a single instrument. Except as amended herein, the Original Agreement, as amended by the First Amendment, shall remain valid and subsisting as originally provided therein. City of Lubbock, TX OWNER By Printed Name David A. Miller Title Mayor Date August 24, 2006 ATTEST: By �n /?L- Rebecca Garza, City Secretary Black & Veatch Corporation ENGINEER r By Printed Name j�It a /00(lol 1, V..j Title Date 1-7 Zael AT Z�W raSt��W By Wanda Astwood, Administrative Assistant APPROVED AS CONTE : Thomas L. Adams, Deputy City Manager APPROVED AS T t- B y Richard Casner, First Asst. City ttorney milcityatt/Richard(Black&Veatch — Amend 2 August 16, 2006 Pa Resolution No. 2006-RO410 August 24, 2006 ATTACHMENT A Item No. 6.9 TO AMENDMENT NO.2 TO CONTRACT FOR ENGINEERING SERVICES Owner: City of Lubbock, Texas Engineer: Black & Veatch Corporation Project: Water Resources Improvements B. PART 2 — DETAILED DESIGN (Anticipated Duration 12 months) Scope of Services Black & Veatch is currently providing engineering services related to renovation of the City of Lubbock (City) Southeast Water Reclamation Plant (SEWRP). The project includes an evaluation of alternative effluent discharge locations to the North Fork Double Mountain Fork of the Brazos River (NFDMF). Potential discharge locations include the Canyon Lakes, near the SEWRP, and below Lake Ransom Canyon, which is the existing discharge location. The Texas Commission on Environmental Quality (TCEQ) recently conducted water quality modeling of the NFDMF using the computer simulation model QUAL-TX. The study area included the river segment from just upstream of the SEWRP (Lake 6 Dam) to Buffalo Springs Lake. In order to evaluate alternative discharge locations in the Canyon Lakes and downstream of Lake Ransom Canyon, the TCEQ model will be expanded to include the Canyon Lakes and the NFDMF from below Lake Ransom Canyon to the Route 380 bridge near Post, Texas. A separate hydraulic model, HEC-RAS will be constructed from Canyon Lake 1 to Buffalo Springs Lake for the purpose of developing the hydraulic coefficients and exponents required for the QUAL-TX model. The coefficients and exponents for the river segment from below Lake Ransom Canyon Lake to Route 380 were developed as part of the 1990 B&V Water Quality Modeling Study, which was conducted as part of an Engineering Plan for upgrades to the WWTP. Therefore, a HEC-RAS model of this segment will not be necessary. The 1990 B&V Water Quality Modeling Study also included a limited amount of water quality 3 sampling in the Canyon Lakes and in the river segment from Ransom Canyon Lake to Route 380. To the extent possible this data and other available water quality data will be used to calibrate the model, although it will be difficult to achieve a reliable calibration of the model from below Lake 6 to Lake Ransom Canyon because effluent is currently not being discharged into this reach of the river. Preliminary QUAL-TX modeling by TCEQ and B&V indicate that effluent discharged to the river near the SEWRP would result in a minimum DO concentration (sag) at some point in the upstream half of Buffalo Springs Lake. Thermal stratification in the reservoir during the summer months may compartmentalize the water column above and below the thermocline. It is possible that the warmer water entering the reservoir would flow through the upper layer, which should better aerated compared to a flow through the entire water column. If the flow is through the upper layer, the reservoir would have a higher capacity to assimilate the BOD in the effluent, resulting in a somewhat higher DO. This project includes sampling of the water column in the reservoir to determine the potential presence of thermal stratification. The reservoir will also be sampled for background chlorophyll a, a constituent of the algae, which produce DO during photosynthesis. Task 1 Project Initiation Task 1.1 Contact TCEQ TCEQ will be contacted regarding questions about the Agency's QUAL-TX model of the (NFDMF) from the Lubbock WWTPs to Buffalo Springs Lake. The questions will be related to the model calibration approach, and assumptions for CBOD, ammonia decay rates, sediment oxygen demand (SOD) rate, stream and reservoir re -aeration rates, and stream and reservoir channel cross -sections. Clarification will be requested on the applicable aquatic life dissolved oxygen (DO) criterion for the unclassified segment of the NFDMF River above Ransom Canyon Lake. The segment from below Ransom Canyon Lake to the confluence of the Double Mountain Fork of the Brazos River is classified with a "Limited" aquatic life use. The average daily DO criterion for a Limited aquatic life use is 3 mg/L. It appears that the DO criterion for the unclassified segment is 5 mg/L. A memo documenting this task will be prepared. 4 Task 1.2 Obtain and Review Existing Information The existing TCEQ QUAL-TX model will be extended to include the Canyon Lakes, 1 through 6. And downstream of TCEQ's model, the model will be extended to include all of Buffalo Springs Lake, Ransom Canyon Lake, and approximately 46 miles of the NFDMF River downstream to Route 380 near Post, Texas. Development of the extended model will be based on existing information, which will include the following sources: • TCEQ QUAL-TX model input run files for various effluent discharge scenarios • Flood Insurance Study (FIS) hydraulic models from Lake 1 to 50`h Street in Lubbock, which is about 1.6 miles downstream of Lake 6 dam. • GIS aerial photos, 1 foot digital contours, and Digital Terrain Model (DTM) from the City • Design drawings with elevation contours of Buffalo Springs Lake • Appendix D, Water Quality Modeling Study, which was conducted by B&V in 1990 as part of an Engineering Plan for upgrades to the WWTPs. The study included Streeter Phelps models of the Canyon Lakes and the NFDMF River from below Ransom Canyon Lake to Route 380. The NFDMF River between Lake 6 and Buffalo Springs Lake was not included in the study. Task 1.3 Conduct Field Reconnaissance B&V modeling staff will conduct limited field reconnaissance of the modeling study reach, which will consist of driving to various bridge crossings and inspecting and photographing river and lake conditions. This will not include surveying, which is not anticipated to be required for this analysis. Task 2 Develop Hydraulic Model A hydraulic model of the Canyon Lakes; the free flowing section of the NFDMF River to Buffalo Springs Lake; Buffalo Springs Lake; and Ransom Canyon Lake will be configured and run for the purpose of developing hydraulic coefficients and exponents that will define the hydraulics for the QUAL-TX model. A preliminary review of the TCEQ's QUAL-TX model suggests that the assumed hydraulic coefficients and exponents significantly underestimate river velocities in the free flowing section. It is not expected that a hydraulic model will be required for the new QUAL-TX model segment below Ransom Canyon Lake to Route 380 because it appears that appropriate hydraulic coefficients and exponents were developed as part of the 1990 B&V water quality modeling study. The coefficients and exponents were based on a dye time of travel study conducted by Alan Plummer 5 and Associates, Inc. (APAI). APAI also conducted dye studies for the Canyon Lake and the reach from below Lake 6 to Buffalo Springs Lake for the 1990 study. The dye studies will be used to calibrate the hydraulic model. Task 2.1 Develop Hydraulic Models The HEC-RAS program will be used to develop the hydraulic models. The existing HEC-RAS model, developed for the Lubbock FIS, should be sufficient for the river reach from Lake 1 to 50t" street. This model will be extended to include the free flowing section of the NFDMF River from 501" Street to Ransom Canyon Lake dam. Channel cross sections of this segment obtained by APAI for the 1990 B&V modeling study will be primary source of data required to build the HEC-RAS model for the free flowing segment. The survey data will be supplemented by the City's Digital Terrain Model. Elevation contours, and the design drawing for Buffalo Springs Lake will be used to develop cross sections for the reservoir. If design drawings for Ransom Canyon Lake are not available, the cross -sections will be estimated from existing aerial photography and elevation contours. The HEC-RAS model will be calibrated based on the dye time of travel study conducted by APAI for the the 1990 B&V modeling study.. The calibrated HEC-RAS models will be run for a range of river flows expected for the various effluent discharges to be evaluated in Task 4.1. The simulated velocities and flow depths will be used to develop the velocity and depth coefficients and exponents used by the QUAL-TX model in Task 3.2. Task 3 Develop New QUAL-TX Model The QUAL-TX model developed by TCEQ will be extended both upstream and downstream as previously described. Task 3.1 Expand Model Segmentation The study reach for the TCEQ QUAL-TX model is approximately 9.9 miles from the WWTPs to near the Comanche Road Bridge crossing of Buffalo Springs Lake. The new model will be expanded to include approximately 8 miles of the Canyon Lakes; the section of Buffalo Springs Lake from Comanche Road to the dam; Ransom Canyon Lake; and approximately 46 miles of free flowing river from Ransom Canyon Lake to the Route 380 Bridge. The TCEQ model was configured using metric units. The expanded models will be configured in English units to make it more user-friendly. 3 Task 3.2 Incorporate Model Hydraulics The velocity and depth coefficients and exponents developed in Task 2.2 will be input to the QUAL- TX model from Lake 1 to Ransom Canyon Lake dam. The coefficients and exponents for the river segments from Ransom Canyon Lake dam to Route 380 will be based on the coefficients and exponents developed for the 1990 B&V modeling study. Task 3.3 Conduct Sampling of Buffalo Springs Lake Sampling of Buffalo Springs Lake will be conducted during one sampling period in the summer of 2006 at five locations in Buffalo Springs Lake and one location in the NFDMF Brazos River immediately upstream of the headwaters of the lake. Sampling at each location will include field measurements of dissolved oxygen (DO), pH, temperature, conductivity, and Secchi disc depth. A near surface water sample will be collected at each station and analyzed for chlorophyll a by a qualified laboratory. A Sampling Work Plan will be developed in consultation with TCEQ prior to conducting the sampling. This plan will describe, at a minimum, the following study components: • Monitoring locations; • Types of samples or measurements; 0 Parameters, analytical methods, and, as appropriate, preservation methods and container requirements; • Identification of responsibility for implementation of specific study activities; and • Quality assurance procedures. After completion of the sampling program, a report describing the study conducted and summarizing the data obtained will be prepared and submitted to the City for review and comments. Task 3.4 Calibrate Models The 1990 B&V Water Quality Modeling Study included a limited amount of water quality sampling in the Canyon Lakes and in the river segment from Ransom Canyon Lake to Route 380. To the extent possible, the data will be used to calibrate these segments of the QUAL-TX models. A search for additional sampling data for the other three segments will be conducted, and if available, this data will also be used in calibration of the model. The model will be calibrated for CBOD and ammonia decay rates, SOD, and re -aeration rates. The USEPA publication Rates, Constants, and Kinetics VA Formulations in Surface Water Quality Modeling will be used to validate the calibration parameters and estimate appropriate parameter values for which calibration is not possible from existing data. To the extent possible, the model will also be calibrated for chlorophyll a, using data obtained in Task 3.3. Task 3.5 Check Model Sensitivity The critical model calibration parameters, CBOD and ammonia decay rates, SOD, re -aeration rates, and algae maximum specific growth rate, will be checked for their sensitivities in affecting model predictions for DO and chlorophyll a. This will be accomplished by making runs for each of the models using the above model parameters that have been increased and decreased by 25 percent of their calibrated values. Task 4 Evaluate Discharge Alternatives Task 4.1 Develop Discharge Alternatives The calibrated models will be used to evaluate scenarios of effluent discharge alternatives. The alternatives will include various combinations of effluents flow rates at various discharge locations.. The discharge locations will include the Canyon Lakes, the NFDMF River near the WWTPs, and increased flow at the existing discharge location below Ransom Canyon Lake. Task 4.2 Evaluate Discharge Alternatives The models will be run for up to 10 scenarios developed in the previous task. The primary consideration for each of the alternatives is impact on DO in the lakes and rivers. It appears that no alternative should result in a minimum DO concentration below 5 mg/L from the Canyon Lakes to Ransom Canyon Lake and a minimum DO concentration below 3 mg/L from Ransom Canyon Lake to the confluence of the DMNF River; however, these criteria should be verified by TCEQ. Task 5 Prepare Technical Memos Task 5.1 Prepare Model Development Memo Upon completion of Task 3, Develop New QUAL-TX Model, a memo to document the work completed to that point in the study will be prepared. This will include a preliminary evaluation of the discharge alternatives in Task 4.2. A draft memo will be submitted to the City for review and comments, which will be addressed in the final version of this memo. Task 5.2 Prepare Study Memo Upon completion of Task 4, Evaluate Discharge Alternatives, a memo documenting the work for the entire study will be prepared and submitted to the City for review and comments, which will be addressed in the final version of this memo. Task 6 Meetings and Presentations Task 6.1 Project Initiation Meeting with City B&V modeling staff will meet with City staff to review the scope of work and to address potential questions and concerns. The meeting will be scheduled immediately following the field reconnaissance, Task 1.3, so that pertinent information learned during the reconnaissance can be shared with City staff. Task 6.2 Present Updated QUAL-TX Model to City and TCEQ The model development memo in Task 5.1 will be presented to City staff and TCEQ staff. Task 6.3 Present Study Results to City and TCEQ The study memo in Task 5.2 will be presented to the City staff and TCEQ staff. Z' Resolution No. 2006-RO410 ATTACHMENT B TO AMENDMENT NO.2 TO CONTRACT FOR ENGINEERING SERVICES Owner: City of Lubbock, Texas Engineer: Black & Veatch Corporation Project: Water Resources Improvements Compensation For the services covered by this Amendment No. 2 to Agreement for Engineering Services, the Owner agrees to pay the Engineer as follows: For all services described in Amendment No. 2 to Agreement for Engineering Services, an amount equal to the Engineer's actual payroll costs times 2.25, plus reimbursable expenses at cost and plus subcontract billings times 1.10, with a total not to exceed $86,000. 2. It is understood and agreed: That the Engineer shall start the performance of the services listed below within ten (10) days of receipt of Notice to Proceed (NTP). That the Engineer shall keep records on the basis of generally accepted accounting practice of costs and expenses and which records shall be available to inspection at reasonable times. 10