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ST8402-CS 890525GINN, INC. May 25, 1989 Dallas Water Utilities Engineering Department 320 E. Jefferson, Rm. 211 Dallas, Texas 75203 CONSUL' FING ENGINEERS Attention: Mr. T. W. Stewart, Manager - Water & Sewer Design Re: Denton Tap Road Improvements from Sandy Lake Road to Denton Creek, Coppell, Texas. Dear Mr. Stewart: We are writing this letter as the Project Engineer representing the City of Coppell on the above captioned project. On May 19, 1989 we received a Proposal from L. H. Lacy Co. for alleviating the conflict identified in our December 22, 1988 letter, between the Dallas Water Utilities 30" water line and the proposed paving subgrade and storm sewer lateral D-22. Copies of this Proposal were sent to Mr. Tony Almeida and Mr. Steve Hardy of Dallas Water Utilities without the knowledge of the City of Coppell or Ginn, Inc. Consulting Engineers. L. H. Lacy Co.'s Proposal is being reviewed by our office and has been found to contain some technical errors. In principle, however, it appears possible that the conflict with the subgrade can be alleviated by removal of some existing pavement and revision of the proposed paving grades to the extent that the cover between the top of the 30" pipe and the bottom of the pavement may be as much as 1.92 feet. Before giving this Proposal further consideration we must ask for Dallas Water Utilities' written comments regarding their acceptability and willingness to perform maintenance and operation of this transmission line which will have to bear HS-20 highway traffic loadings transmitted through 8" of 3000 psi reinforced concrete pavement constructed on a 6" Lime Treated Subgrade and approximately 1'-5" of compacted earth. L. H. Lacy Co.'s Proposal also contains a reference to the shallow cover over the subject water line in the neighborhood of Station 185+00 as addressed in your August 26, 1987 letter to our firm. If it is your desire to reconsider this item, please inform us of your intentions. 17103 Preston Road · Suite 100 · LB 118 · Dallas, Texas 75248 · Phone 214/248-4900 Upon receipt of your written response, we will continue our evaluation of L.H. Lacy Co.'s proposal. Please reply as soon as practical in order to minimize delay of construction of this City of coppell Capital Improvement Project. We thank you for your cooperation on this project. Please call me if you have any questions. Sincerely, John C. Karlsruher, P. Project Engineer enclosures cc: Russell Doyle, P.E., city Engineer H. Wayne Ginn, P.E. Scott Balch, P.E.- L. H. Lacy Co. Ron McAvoy - L. H. Lacy Co. A. V. Almeida - Dallas Water Utilities Steve Hardy - Dallas Water Utilities Mike Parsley - Dallas Water Utilities Randy Fleming File J - 379 (a:525dwu) MAY 15. 1~88 GINN. INC., CONSULTING ENGINEERS 17105 PRESTON ROAD SUITE 100, LB-118 DALLAS~ TEXAS 75248 ATTN: JOHN C. KARLSRUHER. P.E. RE: DENTON TAP ROAD IMPROVEMEN[S FROM SANDY LAKE TO DENTON CREEK (579> PROPOSED ROADWAY GRADES FOR NORTHBOUND LANES FROM STATION 1~+00 TO 1~+75 TO ALLEVIATE INTERFERRENCES WiTH CITY OF DALLAS 50" WATER LINE IN THE SUBGRADE AND LATERAL D-22 DEAR JOHN? ATTACHED FIND COPIES OF I_. iH. LACY CO'S PROPOSAL TO HELP SOLt/E THE INTERFERRENCE WITH THE ABOVE REFERRENCED CITY DF DALLAS WATER LINE. THE L. H. LACY CO. HAS MADE ]-HE FOLLOWING LOGICAL ASSUMPTION IN PROPOSING '[HIS SOLUTION: 1> THE CHANGING OF THE ROADWAY GRADES IN THE ABOVE REFERRENCED LIMITS WILL NOT CHANGE THE DRAINAGE AREA THAT WAS ORIGINALLY DESIGNED TO BE DRAINED BY LATERAL D-22 THE ACCEPTANCE OF THIS ASSUMPTION WOULD INDICATE THE FOLLOWING TO ALSO BE LOGICAL FOR AN INLE~ PLACED ON THE EAST MEDIAN CURB: 1> THE DESIGNATED INLET TYPE AT LATERAL D-22 WILL STILL BE VALID 2) THE DESIGNATED LATERAL PIPE SIZ~ FOR D-22 WILL STILL BE VALID THE POSITIVE DIFFERENCE (*.b~') IN CURB HEIGHT FOR INLET D-22 ASSURES THAT WE CAN PROVIDE ADEQUATE FALL TO THE EXISTING 4X5 R.C.S.C. WE WILL SE DRAINING INTO. THE ADDITIONAL CLEARANCE iS GAINED BY REDESIGNING THE ROADWAY GRADES FROM EXISTING STATION 1~+00 (INSTEAD OF 1~+58). THIS GIVES MORE DISTANCE TO EFFECT A CHANGE IN GRADE. RLEASE NOTE THAT IN REFERRENCE TO COVER OVER THE 50" WATER LINE - AT STATION 185~00 'THE 50" WATER LINE HAS APPROXIMATELY 2' OF DESIGN COVER NEAR THIS STATION. L H. Lacy Company General Contractors 214/357-0146 'Quality Construction fo~ over 65 Years' 10888 Shady Trail P.O. Box 541297 Dallas, Texas 75354-1297 THE L. H. LACY CO. BEL1EVES THIS PROPOSAL HAS EXCELLENT MERI1. AND THAT )l WARRANTS CLOSE CONSIDERATION. IF YOU HAVE ANY QUES1]ONS PLEASE GIVE ME A CALL. RESPECTFULLY SUBMITTED, CC: ENC: SCOTT BALCH. P.E.. L. H. LACY CO., PROJEC1 MANAGER FILE 510 CORRESPONDENCE TONY ALAMEDA. CITY OF DALLAS PUBLIC WORKS STEVE HARDY, CITY OF DALLAS WATER & SEWER D~S1GN ONE tl> COPY OF SL!F~VEY NO]~S [)P E~.IS]IN~ DEN~[)N lAP ~r ~ c ~ ONE (i) COPY EACH O~ MAR~<ED-UP SHEE~S 11~ 12 OF THE PLANS ONE ~1> COPY OF L1ST DETAILING PROPOSED GRADES. CR£~SS-SLOP~S. AND PROPOSED VERTICAL CURVES 1NFORMA]IO~ ONE (]) COPY OF SURVEY NOTES OF CONFLICT ~ LA]~RAL D-22 L. H. LACY COMPANY - DENTON TAP ROAD, PROJECT (379) PROPOSED GRADE CHANGES @ N.B. LANES TIE-IN @ SANDY LAKE 70 AVOID CITY OF DALLAS 50" WATER LINE IN PLAN SUI~GRADE INTERFERRENCE WIT~ REFERENCE: LOOKING UPSTA'FION REFERENCE: POSi]'IVE (+) X-SLOPE FROM MEDIAN '1'0 R.O.W. STAl I ON NOTES ~ PROPOSED PROPOSED PROPOSED ~ PLAN PLAN PLAN ~ RIGHI MEDIAN X-SLOPE I RIGHT MEDIAN X-SLOPE : TlC TlC : TlC TlC 166 + O0 MATCH : 495.27 495.19 (0.0024) : 495.27 495.19 (0.0024) 166 + 50 166 + 75 PVC-CURVE 167 + O0 167 + 08 SAG-CURVE 167 + 50 PVI-CURVE 168 + 00 168 + 25 PVCC-CURVEI/21 168 + 50 169 + 00 PVI'-CURVE 169 + 50 169 + 75 PVF.-CURVE 170 +. O0 N/C 170 + 50 N/C 171 + O0 N/C 495.02 494.75 (0.0085) 494.89 494.50 (0.0115) ; 494.05 494.51 0.0076 494.85 494.36 (0.0144) : 495.77 494.12 0.0105 494.88 494.55 (0.0156) 495.50 494.59 (0.0209) I 495.75 494.10 0.0109 495.43 494.72 (0.0209) ~ 494.39 494.54 0.0044 495.76 495.05 (0.0209) : 494.98 494.94 (0.0012) 496.10 495.39 (0.0209) : 495.58 495.54 (0.0071) 496.31 495.60 (0.0209) : 496.31 495.77 (0.0159) 496.45 495.72 (0.0209) ) 496.43 495.72 (0.0209) 496.26 495.55 (0.0209) : 496.26 495.55 (0.0209) 496.01 495.50 (0.0209) : 496.0] 495.30 (0.0209) 495.51 494.80 (0.0209) : 495.51 494.80 (0.0209) 495.01 494.50 (0.0209) : 495.01 494.50 (0.0209) PROPOSED VERTICAL CURVE INFORMATION CURVE I (EASF T/C) M = +.78 SLOPE 1= -.50% SLOPE 2= +1.66% CURVE 1 (MEDIAN T/C) M = +.78 SLOPE 1= -.92% SLOPE 2= +1.66% CURVE 2 (EAST T/C) M = -.70 SLOPE 1= +1.b6% SLOPE 2= -1.00% CURVE 2 (MEDIAN T/C) M = -.70 SLOPE 1= ~1.66% SLOPE 2= -1.00% i * , t ,~1 f : I i