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Home My WebLink About3557; Carlsbad Blvd Las Encinas Creek & Bridge; Carlsbad Blvd Las Encinas Creek & Bridge; 2012-04-241 2012 Jack L. Abcarius Nolte Associates, Inc. April 24, 2012 Bridge Elevation – 4/19/2012 Bridge Revetment Monitoring Report for the City of Carlsbad and the California Coastal Commission Las Encinas Creek Bridge Br. No. 57C-0790L 2 April 24, 2012 State of California – The Natural Resources Agency California Coastal Commission San Diego Area 7575 Metropolitan Drive, Suite 103 San Diego, CA 92108-4421 SUBJECT: 2012 Bridge Revetment Monitoring Report Las Encinas Creek Bridge along Southbound Carlsbad Boulevard Bridge No. 57C-0790L City of Carlsbad, California In accordance with Special Condition No. 2 set by the California Coastal Commission to approve the City of Carlsbad’s Application No. 6-09-051, Nolte Associates, Inc., an NV5 company, is submitting this third report for the Revetment Monitoring Program for Las Encinas Creek Bridge, Br. No. 57C- 0790L. This special condition states that “the monitoring report shall be submitted to the Executive Director and City of Carlsbad Engineering Department yearly after each winter storm season but prior to the 1st of May starting with May 1, 2010”. The remaining two subsequent reports shall be submitted prior to May 1st of future years. Condition of Revetment The rip-rap along the west edge of southbound Carlsbad Boulevard starts at Station 104+20.00 to 105+37.50 and 105+81.00 to 110+08.00. The stationing is measured along the centerline of southbound Carlsbad Boulevard, and runs from north to south. Bridge construction and rip-rap placement was completed on May 28, 2010. In order to control the location of the toe of slope on the beach side during construction, the contractor placed sheet piles located 51 -10 ± from the centerline roadway prior to the installation of the rip-rap. This dimension coincided with the High Tide Contour Line of 4.77 (NGVD29) which was equivalent to 7.65 (MLLW) as surveyed during the design phase of this project in 2009. The third High Definition Scanning was performed on March 23 of 2012. For ease of comparison, the original monuments installed in 2010 were surveyed and results are shown in a tabular format in this report (Appendix A). It should be noted that this beach area is highly dynamic due to the constant wave action that deposits and removes small sized cobbles along the length of this project as evidenced in the photos shown in this report. Although the monuments show very little evidence of movement, the sandy beach was completely covered with cobbles up to 4" or 5" in size. Following are some photos taken on April 19 of 2012 showing the current condition of the rip-rap. These photos are used for comparison to the baseline condition post construction of 2010. We’ve also included new scanned images to compare against the images developed in 2010. 3 View looking North (2010) View Looking North (2012) Rip-Rap Looking Northeast (2010) Looking Northeast (2012) 4 Rip-Rap Looking South (2010) Looking South, April 19, 2012 Rip-Rap Looking South, Past the Bridge (2010) Looking South, Past the Bridge, April 19, 2012 5 6 7 For the 5 year rip-rap monitoring plan, a control system was established and an initial survey was made on June10-11, 2010. Control was established by GPS based on CCS83, Epoch 1991.35 coordinates per City of Carlsbad Survey Control, ROS 17271. The Benchmark is OC-147 (ROS 17271 point #1433), having a NGVD 29 elevation of 50.56 . Five control points were set in the project vicinity, but outside of the rip-rap for future surveys, including a 1 brass disc mounted on the bridge, identified as M-5. Additionally, six brass caps were set into boulders of the rip-rap and surveyed both horizontally and vertically for future monitoring. These are identified as M-1, 2, 3, 4, 6, and 7. All these monuments are clearly shown on the “Key Map to Control and Check Points” drawing included in this report (Appendix B). The control points were documented photographically as well as surveyed for future use. Note that during our 2012 survey of March 23, all monuments were visible except for Monument M-6, which was buried with cobbles. Bridge Elevation View Looking North-East (2010) (April 2012) 8 High Definition Scan Model - Section Key (See 2010 – 2012 Profile Sections as an insert at end of this report) Future Reports Nolte will continue performing a full High Definition Scan annually through 2014, and each scan will be compared to the 2010 baseline model and corresponding section views. The Table in Appendix A has been set up for this comparison. This will allow for measurement and recording of all nine monuments vertically and horizontally so that the performance of the rip-rap can be evaluated. This evaluation will determine maintenance strategies over the monitoring period. This report is prepared after each scan and submitted to the City of Carlsbad. Two hard copies as well as an electronic version are sent to the City, who will in turn forward to the California Coastal Commission in accordance with the CCC conditions of approval as set forth in the CDP Application No. 6-09-051. Should you have any questions concerning this letter report, please feel free to contact me at (858) 385-2128. Sincerely, Nolte Associates, Inc. ______________________ Jack Abcarius, P.E. Engineering Manager Approx. Sta. 104+20 ~Sta. 105+37.50 ~Sta. 105+81 ~Sta. 110+08 Las Encinas Creek Bridge Annual Revetment Monitoring Project No. SDB044900 Mon. No. North East Elevation North East Elevation Variation North Variation East Variation Elevation M-1 1987170.037 6232576.644 14.893 1987170.029 6232576.643 14.882 -0.008 -0.001 -0.011 M-2 1987189.332 6232558.688 8.516 1987189.332 6232558.694 8.499 0.000 0.006 -0.017 M-3 1987278.205 6232540.045 15.696 1987278.196 6232540.040 15.680 -0.009 -0.005 -0.016 M-4 1987333.538 6232508.076 8.588 1987333.536 6232508.071 8.570 -0.002 -0.005 -0.018 M-5 1987425.621 6232501.512 15.913 1987425.609 6232501.507 15.911 -0.012 -0.005 -0.002 M-6 1987555.970 6232428.560 6.990 1987555.970 6232428.538 6.994 0.000 -0.022 0.004 M-7 1987585.650 6232423.510 9.645 1987585.639 6232423.454 9.634 -0.011 -0.056 -0.011 4" B.D.1 N/A N/A N/A 1987231.984 6232553.516 14.141 #VALUE! #VALUE!#VALUE! L.S. 79901 N/A N/A N/A 1987487.706 6232476.664 16.160 #VALUE! #VALUE!#VALUE! 1 Monuments placed by others; Nolte does not have the 2010 coordinates and elevations to compare against. Highlighted cells represent the largest values measured. Mon. No. North East Elevation North East Elevation Variation North Variation East Variation Elevation M-1 1987170.037 6232576.644 14.893 1987170.005 6232576.653 14.914 -0.032 0.009 0.021 M-2 1987189.332 6232558.688 8.516 1987189.363 6232558.685 8.521 0.031 -0.003 0.005 M-3 1987278.205 6232540.045 15.696 1987278.194 6232540.048 15.659 -0.011 0.003 -0.037 M-4 1987333.538 6232508.076 8.588 1987333.545 6232508.084 8.577 0.007 0.008 -0.011 M-5 1987425.621 6232501.512 15.913 1987425.592 6232501.516 15.916 -0.029 0.004 0.003 M-6 1987555.970 6232428.560 6.990 N/A3 N/A3 N/A3 #VALUE! #VALUE! #VALUE! M-7 1987585.650 6232423.510 9.645 1987585.690 6232423.507 9.630 0.040 -0.003 -0.015 4" B.D.2 1987231.984 6232553.516 14.141 1987231.985 6232553.505 14.135 0.001 -0.011 -0.006 L.S. 79902 1987487.706 6232476.664 16.160 1987487.713 6232476.717 16.159 0.007 0.053 -0.001 2 Coordinates and elevations are based on Nolte's 2011 Survey. 3 Monument M-6 was buried with cobbles Highlighted cells represent the largest values measured; Less than a 1/2" vertically and 3/4" horizontally. Mon. No. North East Elevation North East Elevation Variation North Variation East Variation Elevation M-1 1987170.037 6232576.644 14.893 -1987170.037 -6232576.644 -14.893 M-2 1987189.332 6232558.688 8.516 -1987189.332 -6232558.688 -8.516 M-3 1987278.205 6232540.045 15.696 -1987278.205 -6232540.045 -15.696 M-4 1987333.538 6232508.076 8.588 -1987333.538 -6232508.076 -8.588 M-5 1987425.621 6232501.512 15.913 -1987425.621 -6232501.512 -15.913 M-6 1987555.970 6232428.560 6.990 -1987555.970 -6232428.560 -6.990 M-7 1987585.650 6232423.510 9.645 -1987585.650 -6232423.510 -9.645 4" B.D.2 1987231.984 6232553.516 14.141 -1987231.984 -6232553.516 -14.141 L.S. 79902 1987487.706 6232476.664 16.160 -1987487.706 -6232476.664 -16.160 2 Coordinates and elevations are based on Nolte's 2011 Survey. Mon. No. North East Elevation North East Elevation Variation North Variation East Variation Elevation M-1 1987170.037 6232576.644 14.893 -1987170.037 -6232576.644 -14.893 M-2 1987189.332 6232558.688 8.516 -1987189.332 -6232558.688 -8.516 M-3 1987278.205 6232540.045 15.696 -1987278.205 -6232540.045 -15.696 M-4 1987333.538 6232508.076 8.588 -1987333.538 -6232508.076 -8.588 M-5 1987425.621 6232501.512 15.913 -1987425.621 -6232501.512 -15.913 M-6 1987555.970 6232428.560 6.990 -1987555.970 -6232428.560 -6.990 M-7 1987585.650 6232423.510 9.645 -1987585.650 -6232423.510 -9.645 4" B.D.2 1987231.984 6232553.516 14.141 -1987231.984 -6232553.516 -14.141 L.S. 79902 1987487.706 6232476.664 16.160 -1987487.706 -6232476.664 -16.160 2 Coordinates and elevations are based on Nolte's 2011 Survey. 2010 2011 Difference From 2010 (Feet) 2010 2012 Difference From 2010 / 2011 (Feet) 2010 2013 Difference From 2010 / 2011 (Feet) 2010 2014 Difference From 2010 / 2011 (Feet)