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Home My WebLink About3190; RANCHO SANTA FE RD ALIGNMENT; 2009/ 2010 STORM DAMAGE ASSESSMENT AND REPAIR RECOMMENDATIONS; 2010-02-16I DUDE.K . . . . . . MAIN OFFICE 605 THIRD STREET I .ENCINITAS. CALIFORNIA 92024 - I 760.942S147 I 800.450.1818 F 760.632.0164 1 February 16, 2010 3385-07 John Cahill . . . . City of Carlsbad I 1635 Faraday Avenue . . Carlsbad, California 92008-7314 .. . . 0 I Subject: Rancho Santa Fe Road Realignment and Bridge Replacement Project, Off- Site Wetland. Mitigation Project - 2009/2010 Storm Damage Assessment I . and Repair RecommeAdations . Dear Mr. Cahill: . . . . . . . As requested by the City of Carlsbad (City), Dudek provides the following analysis of the storm damage that has occurred to date as a result of the winter 2009/2010 storm events, at the off-site I wetland mitigation area associated with the Rancho Santa Fe Road Realignment and Bridge Replacement Project. . . . . . As you know, the off-site wetland mitigation and revegetation portion of the project, being implemented along San Marcos Creek, within the University Commons open space area, was nearing completion of the planting phase of the installation in late November/early December 2009 when several "El Niflo" related storm events hit our area. 'In Dudek' s . opinion, the project was approximately 95% complete at the time the second large storm in early December hit. All that remained to be completed, at that time was for the upper canyon area (i.e., secondary drainage area, east of the quarry) to be hydroseeded and a few areas along the upper and lower creek margins still needed to be hand seeded. - The first winter storms started on November 27 and 28 and continued on December 6 and 7. The 1 . early December storm produced a large rainfall amount in .a short period of time. . In the. San Marcos area, there was approximately 1.5 inches of rainfall in a 24-hour. period. This was a much larger than normal rainfall event. Per discussions with U.S. Army Corps of Engineers Staff they I believe that the December 6 and -7 storm equated to a 10- or 20-year storm event. Additional rain events have occurred since that time, in mid to, late January and early February as well, resulting I , . in continued higher than normal seasonal rainfall amounts. This has lead to additional erosion and further damage to the mitigationlrevegetation areas. In addition, the week long storm event between January 17 and 23 resulted ,in over 5.5 inches of rainfall in the San Marcos area. (Note: I it should be pointed out. that after the first November storm event, 'Dudek made recommendations to the City to conduct remedial repair work to correct the erosion problems WWW.DUDEK.COM 1 Mr. John Cahill I Subject Rancho Santa Fe Road Realignment and Bridge Replacement Project Off-Site Wetland Mitigation Project - 2009/2010 Storm Damage Assessment and Repair I Recommendations I that resulted from that first storm. See Dudek Site Observation Report #8, dated November30, 2009. Dudek also; provided a more comprehensive damage repair assessment and, recommendations, per the city's request, in our letter dated, December 29, 2009.) In Dudek's opinion the project was in substantial compliance with the intended installation program prior to the onset of the early December rain event, as all of the container plants had been installed in the lower canyon area, and only minor hand seeding of these areas was still outstanding. The substantial flood event that occurred on December 6 and 7, which lead to the I .Lake San Marcos dam overtopping, resulted in a significant amount of flood flow passing through the San. MarcOs Creek canyon and through the mitigation area. As the creek flowed through the recently graded and planted mitigation area east of the check dam, the flow diverted I completely from the main creek and flowed almost entirely through the mitigation area, causing significant head cutting, scouring, and resultant deposition of sediment behind the check dam. ' The check dam also overtopped at that time, which lead to significant flood flow moving through the lower mitigation area west of the check dam, eroding soil in. that area, washing out plants and causing deposition of sediment in the lower westerly portion of the site In addition, much of the flow in the existing creek channel also diverted through the recently graded area below the check dam. Since that time, continued flow over the top of the check dam has also lead to undercutting I of the toe of the rip/rap at the downstream side of the check dam. (Note: This undercutting could potentially compromise the integrity of the check dam. This situation should be evaluated further by the City, the contractor, and 0-Day Consultants (i.e., project engineer) to determine if any 1 corrective action is needed.) In addition, significant head cutting and erosion has also occurred in the lower mitigation area below the check dam and sediment deposition has resulted at the west 1 .. end of this: lower area. Approximately 800/o_90% of the container plants installed in the two lower canyon mitigation areas have either been washed away, or have been buried by sediment. The majority of the plantings on .the adjacent slope area have survived, with only .minor damage 1 incurred along the toe of this slope. . . Figure 1 shows the physical layout of the mitigation areas and the locations where the storm I damage has occurred Figures 2-5 show the mitigation areas prior to and after the major storm events I It should be pointed out that 'the physical area (i.e., acreage) originally intended for the wetland mitigation areas still exists The creek flow through these areas has demonstrated that there is I adequate hydrology to support the intended wetland plantings in these areas; however, the problem is that the intended wetland plant 'materials have not had adequate time to become rooted into the soil and become adequately established to withstand the flood flows As a result 3385-07 DUDEK. 2 . ' . February 2010 I . H I. H. Mr. John Cahill . . . I Subject: Rancho Santa Fe Road Realignment and Bridge Replacement Project, Off-Site Wetland Mitigation Project -' 2009/2010 . Storm Damage Assessment and Repair Recommendations I . of the damage, much of the plant material has been lost and there is currently little to no plant 'material remaining in these areas to help stabilize the soil surfaces against erosion Approximately 800/6-90% of the plant'inateniat in these areas have been lost or have been buried by sediment Only 100/6_20% of the total installed plant material in this lower canyon area have survived, primarily along the margins of these areas. Over time this plant material should I establish and should help to stabilize the edges of these areas, and will also provide a future seed source for natural native plant recruitment However, until the remaining disturbed areas fill in, these bare areas will continue to be subject to additional erosion and further disturbance Dudek I expects that there will be significant natural native plant recruitment that will likely take place within the disturbed areas during this coming spring penod, resulting from the natural seeding I and recruitment process. Natural . seed distribution has likely taken place as part of the soil deposition process and from the flood flow dispersion of seed throughout the areas. More. seed dispersal will likely occur as the surrounding native plants go to seed and spread into the area. I With sufficient soil moisture and adequate growing conditions these areas should experience significant natural recruitment. . . I It should be pointed out that the previous University Commons wetland mitigation areas that were installed in this same creek area, have been in the ground since November 2005 I (approximately 4 years) and are still doing well. These areas have only incurred minor damage from the recent flood events, since the plant materials were already well established. These areas are now able to withstand these types of storm events. Photographs of the University Commons I areas are shown on Figure 6 included herein. As a result of the redirected creek flow through the east end of the mitigation area (i.e., area east of the check dam), the brow ditch and slope bordering the access road have become undermined and the slope area has given way, causing the brow ditch to break-off just east of the outfall point into the upper basm The spillway and rip/rap at the outfall location have also been undermined and they are currently in jeopardy of failing Dudek has recommended to the City that this area be repaired to help stabilize these areas against the continued winter, flood flow. This repair work has been previously considered by the City in coordination with the contractor Sierra Pacific West (SPW), but to our knowledge has not yet been authorized. I Figure 1 included herein, shows the physical configuration of the mitigation areas and indicates where the flood damage has occurred. Of the total 3.65 acres of intended wetland mitigation .I acreage within the entire off-site project area (i.e., both wetland creation and. enhancement areas), both in the lower canyon (i.e., 2.71 acres), as well as within the upper canyon (i.e., 0.94 acre), approximately 1 33 acres of the planted area has been disturbed or severely damaged by DUDEK I 3385-07 3 . . February 2010 El I Mr. John Cahill Subject: Rancho 'Santa Fe Road Realignment and Bridge Replacemelit Project, Off-Site Wetland Mitigation Project - 2009/2010 Storm Damage Assessment, and Repair Recommendations the flood flows This equates to approximately 35% of the total overall mitigation area having been impacted The damage occurred primarily in the lower canyon area, with only minor damage incurred in the upper canyon It should be pointed out that the upper canyon area, east of the old quarry and waterfall area, incurred only minor damage from the flooding, and the majority of the plantings in those areas have survived and are doing well Some minor damage occurred to the enhancement area in the main creek The storm events that have occurred to date (between November 2009 and February 2010) during this winter period, occurred on the following dates, with the approximate amount of rainfall for each storm event noted (Note Data taken from the National Oceanic and Atmospheric Administration (NOAA), National Weather Service Forecast Office, San Diego, Ca, hydrologic data records and from Fox 5/The Weather Underground precipitation source information): November 27 and 28, 2009, light ram event, with approximately 0.02 inch of precipitation in the San Marcos area December 6 and 7, 2009, large rain event, with approximately 1.5 inches of precipitation in the San Marcos area, over an approximate 24-hour period December 11, 12, and 13, 2009, moderate rain event, with approximately .0 .43 inch of precipitation in the San Marcos area. January 17 through 23, 2010, week-long rain event, with approximately 5 7 inches of precipitation in the San Marcos area January 26 and 27,2010, light rain in the p.m. of January 26, with approximately 0.21 inch of precipitation in the San Marcos area February 5 through 7,-2010, light rain in p m of February 5 and heavy all day the February 6, with approximately 0 58 inch of precipitation in the San Marcos area Table 1 shows the original habitats and impacts, the mitigation areas and ratios that were required, the acreage that has been damaged due to the flooding and the approximate un- damaged areas that remain I I 1: i'DUDEK 4 3385-07 February 2010 H: Mr. John Cahill I Subject: Rancho Santa Fe Road Realignment and Bridge Replaceiient Project, Off-Site 'Wetland Mitigation Project - 2009/2010 Storm Damage Assessment and Repair I . Reconimendations S . 'table 1. : Mitigation Summary for Impacts and Damage Due to Flooding ,•.f' i- '.' 'V, 4. Mitigation Area Planting Area 7 . . Required Mitigation Areas and Ratios . .. . -. Damaged Due to Flooding (Off site) Mitigation . fImpactsor On site and Off site Locations (Acres) Crëatin Enhàncernent ration' Creation .j Resto damaged . Enhancement Restoratin Habitat Tye Acres)* (Acres) - Permanent Impacts S. (Mit,ationProvidedat Off-siteLdcation)' Southern willow scrub 0.42: '' 1.26 - ' ' 1.19 ' ' 0.07 • .. (3:1) SWS Disturbed wetlands ' 0.27 0.27' 0.54 ' 0.14 ' 0.67w :() (2:1) • . FWM FWM. Waters Of the U.S. ' 0.24 '. 0.24 ' -. - 0.00 -' 0.247* ' / • FWM Subtotals 0.93 1.77 ' .0.54 ' - . 1.33 : - - 0.98 Temporary Impacts (Mitigation Provided Partially at the Os-site, as ell as atOff-siteLôcations) '. Southern willow scrub 0.97 ' 0.54 0.54 -' On-site mitigation ' ' (1:1) (at bridge) : at on-site bridge Southern willow scrub- . ' . ' ' ' area) Off-site mitigation (university commons- site) . ... ' . •• ' ' . '. 5 0.43 0.86 0.00 • 0.00 . ' 1.29 (1:1) (2:1) • - ' _____ __________ ______ ______ Subtotals 0.97 ' 0:43' . 0.86 0.54 .. -. - : 1.83 Grand Totals 1.90 . 2.20 1.40 0.54 1.33 .. J 0.00 0.00 ' 2.81 (rounded) I Total Mitigation Required On site at Bridge Location: 0.54 acre. Total Mitigation Required Off site at University Commons: 3.6 acres. Total Mitigation Required Both On site and Off site: 4.14 acres: * Permanent impacts resulting from the Rancho Santa Fe filling and grading. . •. . S Temporary impacts, are being compensated for through on site restoration at a 1:1 ratio at the bridge location, plus additional creation/enhancement acreage credited at a'2:1 ratio at the off site location. Mitigation acreage for impact to disturbed wetlands and waters of the U.S. 'are being compensated for through freshwater marsh 'creation at the off site location. ' : • S S . • HI 'S S • 33557 DUDEK •. . . .' 5 • • '5 5 5 February 2010' I I A / I 1 I I I I . I Mr. John Cahill Subject: Rancho Santa Fe Road Realignment and Bridge Replacement Project, Off-Site- Wetland Mitigation Project 2009/2010 Storm Damage Assessment and Repair Recommendations OPTIONS FOR RESPONDING TO THE STORM EVENT IMPACTS Dudek provides the following alternatives/options for addressing the storm damage impacts that have occurred within the project area. Three options are presented below for consideration by the City. Each option has its own ramifications related to resource agency compliance that the City should consider before moving forward. A Interim Repair Work and Return Areas to Previous intended Design Configuration in Spring 2010 . The first option/alternative the city should consider is to conduct some initial interim erosion control and damage repairs to stabilize the hardest hit locations and then reconfigure and replant the entire mitigation area to its original intended design configuration in late spring 2010. If this alternative/option is elected, then Dudek recommends that the following repair work be conducted immediately in order to help stabilize the areas and to help save what is remaining from the Original planting effort: Install gravel bags on the check dam to divert flows towards the main existing creek channel and away from the graded/plantedareas. . Create a gravel bag diversion structure on the downstream side of the check dam, in order to divert low-flow out of the second low-flow pipe from the west, from flowing into the graded/planted area and instead divert it back into the existing creek area. The eroded slope below the brow ditch, near the end of the access road, needs to be repaired and stabilized The easterly section of brow ditch that failed would not need to be replaced The damaged portion of the concrete brow ditch should be broken-up and either removed from the site, or used as a base below the new rip/rap to be installed in this location Reinstallation Of that portion of the brow ditch is probably not necessary, as it carries little runoff from the road/trail area Secure any loose/washed-out irrigation pipe and heads, and temporarily re-stake the pipe into higher upland positions where possible to help save the systems from further creek damage until future repair efforts can be conducted. Irrigation operation needs to be restored to any areas where plant material is still present, in order to keep this plant material alive All lateral line pipe crossings of the creek channel need to be repaired and should be placed in galvanized pipe sleeves and, securely staked in place, to better protect them against water flow breakage I I L / 3385-07 February 2010 1 Mr John Cahill I .Subject. Rancho Santa Fe Road Realignment and Bridge Replacement Project, Off-Site Wetland Mitigation Project - 2009/2010 Storm Damage Assessment and Repair I Recommendations ..- I 5 The irrigation mainline crossing through the area where the creek breached through\the site upstream of the check dam should be re-routed out of the creek channel and secured in another location where it can be better protected against the creek flow. Dudek will I work with the contractor to determine an appropriate location: An interim solution is to securely stake the pipe in place until an alternative location-can be worked out. 6 The irrigation mainline feeding the revegetation areas east of the quarry, in the upper canyon area, needs to be periodically assessed for damage and repaired where necessary I to assure operation of the irrigations systems in the upper area. All creek crossings of pipe and wire should be assessed and repaired and/or secured as necessary. I . 7 Any plant material that was partially washed out of the ground by the flooding, exposing the rootballs should be replanted where, necessary and/or have additional soil added : around the rootballs to help cover the roots and avoid the rotballs from drying out. 8 The upper canyon area should be hydroseeded, as was originally specified / 9. All hand seeding of the remaining wetland areas should be postponed for now and I implemented towards the end of the maintenance period, once the threat of additional flooding has subsided. I 10. The eroded/damaged soil areas will be left for now, until additional remedial grading and repair measures can be determined for iter: implementation in spring 2010. Plant 5materials remaining in these areas shall be left and maintained/irrigated to the greatest I degree possible to save this plant material 11 For plant material that was buried by sediment and can still be detected, the contractor I should dig out sediment from around the plants in order, to help these plants survive and grow up through the sediment I 12 In late spring 2010, (i.e., after April 15) return all areas to their original grade elevations and replant all areas per the original planting plans The total quantity of plant materials and species to he installed would be determined by Dudek prior to that time. B Partial Repair Work in Late Spring 2010 As second alternative/option, the City could postpone doing any initial repair work now and could wait until after the threat of additional winter flooding has subsided, which in an "El Niflo" year like this, would be mid April 2010. At that time remedial grading work would take place to repair the eroded/undermined slope area through installation of additional rip/rap material to stabilize the slope In addition, a berm would need to be re-established between the main creek DUDEK 7 3385-07 February 2010 .1 .1 I I I I I I I I I I I I I" I I I I Mr: John Cahill Subject: Rancho Santa Fe Road Realignment and Bridge Replacement Project, Off-Site- Wetland Mitigation Project 2009/2010 Storm' Damage Assessment and Repair Recommendations and the mitigation area A: portion of the deposited sediment from behind the check dam would need to be removed and used to build the berm and to fill and repair, the worst upstream eroded areas. The irrigation system would then need to. be repaired and additional planting would need to be installed per recommendations provided by Dudek, based upon the resultant disturbed areas needing additional planting If this alternative/option is elected, then Dudek' s' recommends that the repair work be conducted in the mid April 2010 and that the work include the following: Repair the eroded slope area east of *the check dam and install additional rip/rap material. Dudek recommends basically leaving the newly formed flow channels through the revegetation mitigation areas, both upstream and downstream of the check dam, however, they should be partially filled with additional native boulders and cobble to help raise the elevation up closer to the intended planting elevations and to help reduce additional erosion and head-cutting that might occur within the channels 3 Dudek recommends removing approximately half of the sediment/sandbar, area (i.e., closest to the check dam) that has developed behind the check dam and utilize this material to help restore the grades of the eroded areas upstream. These' restored areas would then be replanted and reseeded, per direction by Dudek 4. In addition, Dudek recommends that 'a mound/berm be re-established between the existing creek and the mitigation area east of the check dam, in order to' repair the breach where, the creek diverted completely through the mitigation area. Dudek recommends installing a rip/rap check dam with soil fill over it, with surface erosion control fabric protection and plantings to re-establish the grade elevations between the adjacent creek banks and the new mitigation area Low-flow pipes would be installed through the berm to help provide minor flow through the mitigation planting area, along the newly established creek channel This would be designed to help restore partial flow to the main creek channel, while still, providing low flow, through the mitigation area. This will also allow ,for some ponding to be held behind this location, which will help support the intended freshwater marsh habitat in that area Dudek also recommends the use of some type of temporary portable check dam units such as "Environmental Barncade", which would be incorporated into the top of the new mound/berm to protect the mitigation areas from future flood breaching until the plant material growth is adequately established to help stabilize the areas. (Note: These units would need to be left in place for several years I' DUDEK I, ' ' 9 Mr. John Cahill Subject Rancho Santa Fe Road Realignment and Bridge Replacement Project, Off-Site Wetland Mitigation Project - 2009/2010 Storm Damage Assessment and Repair Recommendations I LI I I: i: I I I 1 I. I . I. I .. I. I I ,. I until growth is determined to be sufficient. They can-then be removed later by hand, without the use of mechanized equipment.) : 5.. Dudek also recommends removing some of the sediment/sandbar area that has developed at the far southwest end of the project below the check dam and using this material to help restore the eroded areas in the remaining planting areas below the check dam. These restored areas would then be replanted and reseeded, per direction by Dudek 6. Dudek recommends that the broken irrigation pipescrossing the eroded area be re-routed to the restored planting areas to provide adequate irrigation coverage to the remaining and restored planting areas 7 Dudek recommends that additional wetland trees and shrubs be planted along the new flow channels in late spring 2010 (i.e., after the grading repair work is complete) The quantities of plants would be determined at a later date, based upon survival of the previously planted matenal, amount of natural recruitment of native wetland plants that has been achieved and the resultant remaining open areas that need to be planted. C Delayed Repair Work until Spring 2011 As a third alternative/option, the City would postpone conducting the remedial repair work this year (i.e., 2010), and instead the City would wait and see how much natural- recruitment takes place over the coming-growing season (i.e., approx. one year period). This approach would be designed to leave the erodedldisturbed areas basically as they have been redefined by the creek flooding and would likely not include any future grading. The redefined creek flow and grade elevations of the disturbed areas, as well as the soil deposition areas, would be left in place as they exist after the winter rain events of 2010. Natural: native plant recruitment would be allowed to take place in the disturbed areas. Future plantings would be determined in winter of 2011 based upon the degree of natural recruitment that has been achieved by that time, and additional plantings would be recommended at that time (i.e., in late spring 2011) to supplement the natural plant recruitment. It should be pointed out that this approach runs the risk of. being out of compliance with the resource agency permits and could lead to a delay in the long-term maintenance and monitoring program This approach also leaves portions of the site open to additional erosion and damage from subsequent storm events in 2010 and potentially the following winter, if adequate natural native plant recruitment is not achieved If this approach were taken, then the monitoring :and maintenance program could also potentially get delayed by approximately one year, depending upon the degree of natural recruitment that takes place The 3385-07 February 2010 I S Mr. John Cahill I Subject: Rancho Santa Fe Road Realignment and Bridge Replacement Project, Off-Site Wetland Mitigation Project -. 2009/2010 Storm Damage Assessment and Repair Recommendations I resource agencies could also pose additional mitigation requirements onto the program since there would likely be a resultant delay in fulfilling the original mitigation obligations ' If this alternative/option is elected, then Dudek recommends that the following items be completed, with the following clarifications noted In late spring 2010. (i.e., March/April), repair and secure all loose/washed-out irrigation pipe and heads, and re-stake the pipe into higher upland positions where possible I Irrigation operation would need to be restored to all areas where plant material is still present, in order to keep this plant material alive during the dry periods of the year. In addition, irrigation coverage would need to be re-established to all disturbed soil areas I and intended mitigation areas to help promote the growth of volunteer native wetland species that might recruit into these areas. All.irrigatiori lateral line pipe crossings of the ' creek channel would need to be repaired and would be placed in galvanized pipe sleeves and securely staked in place, to better protect the systems against future flood flow damage. . . In fall/winter of 2010/2011, Dudek or the designated biological monitor at that time, would assess the extent of the natual recruitment that has been achieved in the I .designated mitigation areas and determine a quantity of additional container plants and seed to be applied, to the areas in the spring of 2011. (Note: Plants would need to be ordered a minimum of 4 months pnor to the intended delivery/installation date, to assure I that the specified plant material will be available.) The biological monitoring period would likely need to be extended by approximately one : year to reflect the limited progress of the areas during the 2010 time period. 4. Additional resource agency mitigation requirements, and/or'penalties could possibly result from the City's delay in taking action to repair the site damage in a timely manner. RESOURCE AGENCY PERMIT RAMIFICATIONS OF STORM DAMAGE Dudek recommends that the City be proactive and transparent with the resource agencies about the storm damage that has occurred and notify them as soon as possible about the status of the project and the desired course of action. In Dudek's opinion the project was in substantial conformance with the intended mitigationlrevegetation design at the time of completion of the plantings in early December 2009, prior to the major storm damage If the project had stayed on- track without the storm damage and December 1 had been used as the official start date of the 1207day plant establishment maintenance period, then technically the end of the 120-day period DUDEK S • • ' - 3385-07 10 : ' ' February 2010 I I I' I I I I Mr. John Cahill Subject: Rancho Santa Fe Road Realignment and Bridge Replacement Project, Off-Site Wetland Mitigation Project - 2009/2010. Storm Damage Assessment and Repair Recommendations .. - I would be April 1. That would be the normal time frame at which Dudek would prepare a letter to the resource agencies signifying the completion of the initial installation and plant establishment - period and would designate the formal start of the five year maintenance and monitoring period. 1 However, since the storm damage has occurred, the normal timeline has been disrupted and there are obviously delays to the program that have resulted. In Dudek's opinion, the City should notify the resource agencies as soon as possible regarding - these problems and propose a remedial workladaptive management strategy for correcting the I . problems and moving forward. .The agencies could respond by requesting amendments to the 'permits to address the project changes, or they might simply agree to the proposed repair strategies This may or may not include extending the proposed maintenance and monitoring I period depending upon the decisions, by the applicable agencies. At this point in time Dudek does not know how the agencies will respond and if additional mitigation measures might be I necessary. We do feel however that it would be better for the City to be proactive, rather than waiting to see if the agencies become aware of the problems and impose additional penalties or I other supplemental mitigation requirements. In conclusion, it is Dudek's opinion that-the project was designed and constructed in accordance with the requirements of the resource agency permits, and in compliance with the intended I ' mitigation strategies. The work that was conducted in the field was monitored by Dudek and was found to be in substantial compliance with the project plans and specifications prior to the onset I of the winter rains. The rain events that occurred from late November 2009 through January 2010 were larger than normal "El Niño" related storm events, were unusual and unforseen at the time they occurred and lead to significant flooding of the mitigation areas and subsequent I . ' damage to the revegetation areas. As has been pointed-out, the plant materials and seeded areas did not have adequate time to become'rooted and establish prior to the onset of the. storms and I thus they could not withstand the flood flow. Dudek's opinion is that if the mitigation areas can be reasonably repaired and the damaged areas revegetated, then the City should still be able to meet the long-term goal of the mitigation program. The City. needs to evaluate the three I alternatives/options presented herein and 'decide upon an appropriate course of action. Dudek is committed to helping the City reach a resolution on how to repair the damaged areas and to move forward to a successful conclusion to the installation phase of the mitigation program. 338507 I DUDEK. ' .11 . , ' February 2010 1 lION AREAI ,158 S.F.) If I 0E)OI JNDER AN / / Planting/Seeding Legend - SWS Area (Including lower slope) -MFS Area - CSS Area - Slope EM -FWM Area - Installed Rip-Rap --rr-, r '--(7 '. - -, — ---. - - - - - - - -MAIN CREEK I - _z -_ -• (- 1- -. - -- / --- / - — -_ --- - - -------- - - - APRROX % 10 REMAINII - ----:-0F PLANTED ANDY il --jRRlGATI0N INSTALLAT -AREAJ3 63Ac (27,484 S J)j r6E OFSLOPE - -O -25.J00 100 •... )\... -- ,- -- I " \ - -•-'•. " ,' ' I Rancho Santa Fe Road Bridge Offsite Mitigation Area FIGURE Winter Impact Assessment - West Project Area (Lower Canyon) 1 r I •Y,) F .*_ç.p; .¼ - ii _- 0 * -I . .__, -• Photo 2: Planting (November 2009) Photo 5: Planting (November 2009) -'; 4 = -, *,i._ -,- • t - - 1J' - Photo 1: Planting (November 2009) Photo 4: Planting (November 2009) : -I&-_ -. • :- .. . - h •- - - - - - . - - • • . : -- - - 1.—. çr - - - .- •• 1 J 3 Photo 3: Planting (November 2009) 0 - I. • - •• c, 11110 zip I . -411 0 0- .• - - -I- - -- .- . 0 • IL 0 0 - - 0 Photo 6: Planting (November 2009) Rancho Santa Fe Road Bridge Offsite Mitigation Area FIGURE Site Photographs - Plantings (November 2009) 2 Photo 1: Post Major Storm (December) Photo 4: Post Major Storm (December) Photo 3: Post Major Storm (December) Photo 6: Post Major Storm (December) Photo 2: Post Major Storm (December) Photo 5: Post Major Storm (December) Rancho Santa Fe Road Bridge Offsite Mitigation Area FIGURE Site Photographs - Post Major Storm (December 2009) , •- • ,' 4•• 4' £, N : * .--. .:- - - 14• £ ....,-'-- -.4-'••:- - • • - / •• I 4 4 • ) - - - 1 '\ t3' -, -C -C * =-* -C C - - - -.?_ : - --- - - •- - • - C • - - 1! - - - - - - - • -r--'--- _-. -'• - ---. --p-- - -- -•--• ,4_•_• - L . ;•-..•- ills - Storm I-low (January /L Al 11 WPM - fk -------------- A --- • -.,_--- .-' --I * • -.5* - - . — -- - ' -r ..• a - ~~ -- AN NAZI 6, -- - -' - - - I :;. lW t a J—,;r tp .5 'S..' ~M- MW ii -- _*_ I •- - -- - ----- ____________________ * ' - - - _5•*_ *5• • • - .5-..- p.-. -, j 5-:-;4..5 - 5--- - 5. • A. - .— - r. ; - • .. - If Rj - • - .- '5' . -%.• VS. ._-• .. _______ - - . - : - .. •*J .•-. r'.- - a- - - - - ;-.- .4 - - c-±3, m - -. • . ._ 54- j—: 7 % &. -.• ..- r - - 1 C!) c\..FL IP••_JI_, - -- • ;_ 2 - ... '.5. t4 -;.-- r.(j.*,* I-•••-• -'..• • '• - ; .•- --.5- -.5 4- ,.r II- /( - -.1&. •' 'I 5- - / Ip AssAssmc Photo 1: View looking east into main creek, prior to start of Rancho Santa Fe Road construction. Photo 2: View looking north along University Commons mitigation area after November 2009 storm. Photo 3: View looking north along University Commons mitigation area after December 2009 storm. Photo 4: View looking east of University Commons area, left of construction fence after December 2009 storms. Photo 5: View looking into University Commons mitigation area after January 2010 storms. Photo 6: View looking south at north end of University Commons mitigation area. (January 2010) Rancho Santa Fe Road Bridge Offsite Mitigation Area FIGURE Site Photographs - University Commons Pre and Post Damage Assessment 6