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HomeMy WebLinkAboutSDP 2023-0012; LEGOLAND CALIFORNIA PROJECT 2025; PRELIMINARY HYDROLOGY STUDY; 2023-09-25September 25, 2023 PRELIMINARY HYDROLOGY STUDY FOR LEGOLAND California Project 2025 1 Legoland Drive Carlsbad, CA 92008 SDP2023-0012 CDP2023-0022 (DEV2023-0061) Prepared For: Merlin Entertainments Group US Holdings, A Delaware Corporation 1 Legoland Drive Carlsbad, CA 92008 Contact: Tom Storer Tel: (858) 334-8938 Prepared By: Cl>\Commercial Development Resources Today's Ideas. Tomorrow's Reality. 695 Town Center Drive #110 Costa Mesa, CA 92626 Tel: (949) 610-8997 ~~~-::::::L.=E"""::z:/t'.:?,tt:==~~=====:::::::=, Aaron M. Albertson, P.E. R.C.E. 65513, Exp. 09/30/23 Hydrology Study LEGOLAND California Project 2025 TABLE OF CONTENTS SECTION I. INTRODUCTION .......................................................................................................... 1 II. DESIGN CRITERIA AND ASSUMPTIONS .................................................................. 2 Ill. DISCUSSION ............................................................................................................. 3 A. EXISTING CONDITIONS ...................................................................................... 3 B. PROPOSED CONDITIONS ................................................................................... 3 IV. CONCLUSION ........................................................................................................... 4 V. DECLARATION OF RESPONSIBLE CHARGE .......................................................... 5 VI. REFERENCES ........................................................................................................... 6 ATTACHMENTS ATTACHMENT 1 -LOCATION, PRECIPITATION, AND SOIL MAPS ATTACHMENT 2-EXISTING & PROPOSED HYDROLOGY MAP & CALCULATIONS ATTACHMENT 3-STORM DRAIN SIZING CALCULATIONS ATTACHMENT 4-WATER QUALITY/HYDROMODIFICATION LETTER ATTACHMENT 5 -REFERENCED IMPROVEMENTS PLANS, EXISTING 24" SD CCTV UTILITY INSPECTION -i - Hydrology Study LEGOLAND California Project 2025 I. INTRODUCTION Background/Purpose The purpose of this study is to determine stormwater runoff and site drainage for a 100- year storm event for a proposed redevelopment at Legoland in the city of Carlsbad, California. The proposed project is being completed by Legoland and is located at 1 Legoland Drive in the city Carlsbad, county of San Diego. The studied area consists of approximately 1.65 acres. The project site is bounded by an existing restaurant patio to the north, existing Legoland attraction to the east and south, and private service road to the west. Existing project site consists of a Legoland driving attraction and landscaped area. Proposed re-development consists of removing the driving attraction as well as the sidewalks and railings on the east side of the attraction. Existing landscape areas and underground utilities will be revised as needed. Site elevations range from approximately 158 to 165 feet above mean sea level (MSL). See Site Location Map in Attachment 1. The project site is located within the Canyon de Las Encinas (904.4) hydrologic area of Carlsbad Watershed Management Area (WMA) of the San Diego Region (9). Legoland owns the storm drain network constructed per City Drawing No. 333-2Y and the regional BMPs adjacent to Palomar Airport Road that project runoff flows to constructed per SOP 15-26/C DP 15-50 dated 06/30/2018. The private storm drain system discharges to Canyon de las Encinas, then ultimately the Pacific Ocean. -1 - Hydrology Study LEGOLAND California Project 2025 II. DESIGN CRITERIA AND ASSUMPTIONS Hydrology Methodology Hydrologic calculations were performed to determine the 100-year discharges at critical locations using the Rational Method. A technical description of the rational method is provided in the San Diego County Hydrology Manual dated June 2003. As recommended in the Manual, the rational method was used to calculate the design discharge for the local drainage areas due to the watershed area to the proposed storm drain system being less than one square mile. Runoff calculations were performed in conformance with the requirements of the County of San Diego Drainage Design Manual dated July 2005 and the San Diego County Hydrology Manual dated June 2003 by use of CIVILDESIGN Engineering Software. The design discharges were computed by generating a hydrologic "link-node" model which divides the area into subareas, each tributary to a concentration point or hydrologic "node" point determined by the proposed site layout. The results of the hydrologic calculations are used to design proposed storm drain facilities and are included in Section 3. Hydrologic Parameters/Assumptions Soil Type: Hydrologic soil ratings are based on a scale of A through D, where A is the most pervious, providing the least runoff. Per the soil map from NRCS (see Attachment 1 ), the study area consists entirely of Type B soils. 6-Hour Rainfall Precipitation (Ps): Per San Diego County Hydrology Manual (2003) Rainfall lsopluvial Maps (see Attachment 1 ), the 6-hour rainfall precipitation for a 100- year event is 2.60 inches. The 24-hour rainfall precipitation for a 100-year event is 4.50 inches. The 6-hour rainfall precipitation is within 46-65% of the 24-hour rainfall values, so P6 does not need to be adjusted for the hydrology calculations. Runoff Coefficient (C): Runoff coefficients are per Table 3.1 in the San Diego County Hydrology Manual (2003). Time of Concentration (Tc): The time of concentration is determined using CIVILDESIGN Engineering Software in conformance with the County and City's hydrology manuals. Printouts are included in Attachments 2. -2 - Hydrology Study LEGOLAND California Project 2025 Ill. DISCUSSION Existing Condition The existing project site is developed as an outdoor driving attraction with AC pavement roads, concrete walkway, decorative pavers, landscaped areas, and underground utilities. The existing 1.65 AC studied area consists of 1 major drainage area with 3 subdrainage areas. Existing condition is 64% impervious and 36% pervious surface. All runoff is directed to existing inlets and conveyed by the 24" storm drain line to Legoland's regional stormwater detention basin for hydromodification flow control and treatment BMPs south of the project site. Runoff is then conveyed to Canyon de las Encinas and ultimately the Pacific Ocean. A map of the existing drainage patterns and the runoff calcu lation results are included in Attachment 2. Peak flows for the existing studied area are summarized in Table 1 below. Proposed Condition Proposed development consists of 2 major drainage areas (DA-A and DA-8). The studied area includes project site areas flowing to new onsite inlets, which is approximately 1.65 acres. Proposed project alters existing drainage subareas. Proposed inlets and storm drain laterals are sized to convey flows from a 100-year storm event. All post-development runoff is directed to the existing storm drain system and is conveyed to Legoland's regional BMP as it does in the existing condition. The studied area is comprised of 84% impervious and 16% pervious area. Proposed redevelopment will increase total impervious area for the project site. Project overflows will be discharged to the existing 24" storm drain at the northwest corner of the site. Additionally, the downstream water quality treatment system has already been sized to treat the anticipated increase in impervious area per letter from Luis Para (Attachment 4 -will be provided in next submittal). Therefore, additional flow control or treatment BMPs do not need to be constructed for the proposed project. A map of the proposed drainage patterns and the runoff calculation results are included in Attachment 2. Peak flows for the proposed project site condition are summarized in Table 1 below. Table 1 -Summary of Unmitigated Peak Flowrates Drainage Area: DA-A and DA-B Area (ac) %Imp. 0100 (cfs) Existing Condition 1.65 64% 3.42 Proposed Condition 1.65 84% 3.58 [Progosed -Existing] 0% +30% +4.5% [Existinal Existing 24" CMP SD line will be abandoned and the proposed 24" HOPE SD line will convey existing/proposed runoff to the existing catch basin at the northwest corner of the site. The existing 24" CMP SD line was inspected by AIRX. The CCTV inspection is provided in Attachment 5. The existing 24" SD line shown in the referenced -3 - Hydrology Study LEGOLAND California Project 2025 improvement plan in Attachment 5 was analyzed and determined to have less capacity than the proposed 24" HOPE SD line. Therefore, the proposed 24" HOPE line can convey existing/proposed runoff. See existing/proposed pipe capacity results in Table 2 below. STA 11+37.71 to 13+70.13 Diameter(in) n(CMP) Slope EX 24" CMP Pipe Capatity 24 A(ft2) 0.022 P(ft) 2.30% R(A/P) Q(ft3/s) V (ft/s) STA 13+70.13 to 17+68.30 Oiameter(in) n(CMP) Slope EX 24" CMP Pipe Capacity 24 A(ft2) 0.022 P(ft) 1.00% R(A/P) Q(ft3/s) V (ft/s) IV. CONCLUSION 3.14 6.28 0.5 20.27 6.45 3.14 6.28 0.5 13.37 4.26 New Alignment Propo$ed 24" HOPE Pipe Capacity Diameter(in) 24 A(ft2) 3.14 n(HDPE) 0.012 P(ft) 6.28 Slope 1.00% R(A/P) 0.5 Q(ft3/s) 24.51 V (ft/s) 7.80 Proposed 24" HOPE Pipe Capadty Diameter(in) 24 A(ft2) 3.14 n(HDPE) 0.012 P(ft) 6.28 Slope 1.00% R(A/P) 0.5 Q(ft3'/s) 24.51 V (ft/s} 7.80 The project's storm drain network is sized to convey flows from the 100-year storm event. Storm drain pipe and inlet capacity hydraulic calculations are included in Attachment 3. A portion of the existing 24" storm drain line will be abandoned and replaced with a 24" HOPE storm drain line. Project overflow locations will remain unchanged with runoff discharging to the existing 24" storm drain line at the northwest corner of the site. -4 - Hydrology Study LEGOLAND California Project 2025 V. DECLARATION OF RESPONSIBLE CHARGE I, hereby declare that I am the Engineer of Work for this project, that I have exercised responsible charge over the design of the project as defined in section 6703 of the business and professions code, and that the design is consistent with current standards. I understand that the check of project drawings and specifications by the County of San Diego and City of Carlsbad is confined to a review only and does not relieve me, as Engineer of Work of my responsibility for project design. ENGINEER OF WORK: Commercial Development Resources 695 Town Center Drive #110 Costa Mesa, CA 91626 Tel: (949) 610-8997 Aaron M. Albertson R.C.E. 65513, Exp. 09/30/23 09/20/2023 Date -5 - I Hydrology Study LEGOLAND California Project 2025 VI. REFERENCES 1. City of Carlsbad Storm Water Manual 2008. 2. San Diego County Hydrology Manual (June 2003). 3. San Diego County Drainage Design Manual (July 2005). 4. Web Soil Survey, San Diego Area, California. United States Natural Resource Conservation Service. 5. CIVILDESIGN Engineering Software, ©1991-2018 Version 9.0, Rational Method Hydrology Program based on San Diego County Flood Control Division 2003 Hydrology Manual -6 - Hydrology Study LEGOLAND California Project 2025 ATTACHMENT 1 Location Map Precipitation Maps & Soil Maps VICINITY MAP: 1 Legoland Drive Carlsbad, CA 92008 (NOT TO SCALE) i N I I I I I g • ,..._ .... 33• ' Orange County 32°30' Project Site d 100-yr 6-hr = 2.6 in b (") . ,..._ .,.. .... in .... ;:.. .... .... in ..... . ,..._ .... ., .. · .-· b 0 • ,..._ .... .,.. Riverside County ..___ in v . (0 ...... ..... ·. \ .... \ c,:> k, ';., ·e:r .. · ... ' .. b (") . <O .,.. r-+-';-',-+-------'--;;:.fJ----.--_._,~-'--'-----+--r--/---i--i-49 -~~-...:+---JI.------- ,,. ... -: .. :· .. ~------..... ; : : ':S: .. : • .., :·:=:~.:./ /, 8 . ,..._ in v . <O ..... ..... M e X . ' C 0 (") . <O ..... ..... .. .......... . . ........ "•·... t ·,.;·-. ·•..... . -.' •. •,, •• <.P ·-.. ·•. •·. ... "-'"' ... ·... .... ' \.:it' ... ... ' '. ', • ... ~ ... ._,'\•,.. .... • ...... , • I I I t : : \ \ \, : 41 I I t . ' .......... ,· : in .... . <O .... ..... 33•30• ~ ... -..... :-; ___ -..:] . .. -.... in .,.. «> ..... ..... 33°15' -····•• .................. ., ~3°00' 3 -0 (t) 1~·-· ::!. . .. -·1;. tu ............... -.. 32°45' 32°30' County of San Diego Hydrology Manual Rainfall /sopluvials 100 Year Rainfall Event -6 Hours lsopluvial (inches) DPW ~GIS Sl>- SafiGIS N TKSMN11SPRO\IIDEDWITHOUTWN4.R.NffYOFN'ttKN).Blt1ERf)(PRE$S 4 OR IMPUEO, INCl.UO,NG. 8llT NOT UWTED TO, THE IM"UEDWARJW<TIES OF MERQ(AN'T A&IUTY AND FfTNESS FOR A PARTICUlAR PURPOSE C..,y.iol,t s.,Ql& .. , __ s lhs ~tNY' cx,min mb1nMion llllffltw ~G ~ E :-..,: .. ~ .. -..,_,._ TM ~oduc:I may c:on1an lnbmaton whet, twa ~ r~ _.. peirmalM g,.l"lt«t by 1'homN Brotiwrt Miele. 3 0 3 Miles 1-- 33° 7.o" N J3"7'J7'N ◄llllil N A Hydrologic Soil Group-San Diego County Area, California (21053 -Legoland Project 2023) ◄7IBlO '410'100 470710 4107'l!l 41U7.ll Map Saile: 1:742f pmb!d on A landsalpe (11' X 8.5'') sheet. ----=====--------========Meiers 0 10 «> Ell ----=====--------========feet o ~ ro ~ w Map prqedfon: Web MerollDr c.ome-aiordhltes: WGS84 l:dge tics: lJlM Zone UN WGS84 Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey "7D1ID 33" 7'40"N I i I I I I 47IBJl I 33• 7':n"N 10/1/2021 Page 1 of 4 Hydrologic Soil Group-San Diego County Area, California (21053 -Legoland Project 2023) MAP LEGEND MAP INFORMATION Area of lntere1t (AOI) □ Area of Interest (AOI) Solla Soll Rating Polygon■ D A D AID D 8 □ BID D C □ CID □ D D Not rated or not available Soll R1tln9 LlnH ,_ A -AID -B -BID -C -CID -D . , Not rated or not available Soll Rating Pointe D A C AID ■ B ■ 8/0 Natural Resources Conservation Service a C C CID D D □ Not rated or not available Water Features Streams and Canals Tran1portatlon +++ Rails ~ Interstate Highways US Routes Major Roads Local Roads Bac:kground • Aerial Photography Web Soil Survey National Cooperative Soil Survey The soil surveys that comprise your AOI were mapped at 1:24,000. Warning: Soil Map may not be valid at this scale. Enlargement of maps beyond the scale of mapping can cause misunderstanding of the detail of mapping and accuracy of soil line placement The maps do not show the small areas of contrasting soils that could have been shown at a more detailed scale. Please rely on the bar scale on each map sheet for map measurements. Source of Map: Natural Resources Conservation Service Web Soil Survey URL: Coordinate System: Web Mercator (EPSG:3857) Maps from the Web Soil Survey are based on the 111/eb Mercator projection, which preserves direction and shape but distorts distance and area. A projection that preserves area, such as the Albers equal-area conic projection, should be used if more accurate calculations of distance or area are required. This product is generated from the USDA-NRCS certified data as of the version date(s) listed below. Soil Survey Area: San Diego County Area, California Survey Area Data: Version 16, Sep 13, 2021 Soil map units are labeled (as space allows) for map scales 1 :50,000 or larger. Date(s) aerial images were photographed: Jan 23, 2020-feb 13,2020 The orthophoto or other base map on which the soil lines were compiled and digitized probably differs from the background imagery displayed on these maps. As a result, some minor shifting of map unit boundaries may be evident. 10/1/2021 Page 2 of 4 Hydrologic Soil Group-San Diego County Area, California 21053 -Legoland Project 2023 Hydrologic Soil Group Map unit symbol I Map unit name Rating Acres inAOI Percent of AOI CbB Carlsbad gravelly loamy B 0.1 sand, 2 to 5 percent slopes MIC Marina loamy coarse B 2.4 sand, 2 to 9 percent I slopes Totals for Area of Interest 2.5 Description Hydrologic soil groups are based on estimates of runoff potential. Soils are assigned to one of four groups according to the rate of water infiltration when the soils are not protected by vegetation, are thoroughly wet, and receive precipitation from long-duration storms. The soils in the United States are assigned to four groups (A, B, C, and D) and three dual classes (AID, B/0, and C/0). The groups are defined as follows: Group A. Soils having a high infiltration rate (low runoff potential) when thoroughly wet. These consist mainly of deep, well drained to excessively drained sands or gravelly sands. These soils have a high rate of water transmission. Group B. Soils having a moderate infiltration rate when thoroughly wet. These consist chiefly of moderately deep or deep, moderately well drained or well drained soils that have moderately fine texture to moderately coarse texture. These soils have a moderate rate of water transmission. Group C. Soils having a slow infiltration rate when thoroughly wet. These consist chiefly of soils having a layer that impedes the downward movement of water or soils of moderately fine texture or fine texture. These soils have a slow rate of water transmission. Group D. Soils having a very slow infiltration rate (high runoff potential) when thoroughly wet. These consist chiefly of clays that have a high shrink-swell potential, soils that have a high water table, soils that have a claypan or clay layer at or near the surface, and soils that are shallow over nearly impervious material. These soils have a very slow rate of water transmission. If a soil is assigned to a dual hydrologic group (A/0, B/0, or C/0), the first letter is for drained areas and the second is for undrained areas. Only the soils that in their natural condition are in group D are assigned to dual classes. USO<\ Natural Resources "am Conservation Service Web Soil Survey National Cooperative Soil Survey 4.9% 95.1% 100.0% 10/1/2021 Page 3 of 4 Hydrologic Soil Group-San Diego County Area, California Rating Options Aggregation Method: Dominant Condition Component Percent Cutoff: None Specified Tie-break Rule: Higher USDA Natural Resources :-iiliii Conservation Service Web Soil Survey National Cooperative Soil Survey 21053 -Legoland Project 2023 10/1/2021 Page4of4 Hydrology Study LEGOLAND California Project 2025 ATTACHMENT 2 Existing & Proposed Condition Map & Hydrology Calculations R·E·C Equivalent Area Calculation after the inclusion of LEGOLAND LLC 2025 (DEV2023-0061) for Water Quality and Hydromofication Purposes Date: 06/29/2023 Summary The purpose of this letter is to provide calculations updating the remaining Equivalent Area after the incorporation of the LEGOLAND LLC 2025 Project (SDP2023-012 / CDP2023-0022, DEV2023-0061) as part of the LEGOLANO future developments that are using the LEGOLAND regional BMPs for Water Quality and Hydromodification Compliance. Projects using LEGOLAND regional BMPs do not need to design BMPs for Water Quality or Hydromodification compliance as long as they demonstrate that their impact area is included as part of the area treated by the regional facilities. According to the LEGOLAND Regional Water Quality and Hydromodification BMP report (SOP 15-26 / CDP 15-50, dated 6/30/18) the regional LEGOLAND Water Quality and Hydromodification facilities can treat up to 45.766 acres of additional equivalent area for Water Quality purposes and up to 72.771 acres of additional equivalent area for Hydromodification purposes. After the letter dated 06/28/2023 associated with the LEGOLAND Garden Restroom Project, these areas are currently to 44.482 acres and 71.487 acres respectively. To REC and CDR knowledge, no project has occurred that is not attached at the "Sequence of Calculations of Available WQ & HMP Conditions" table, shown on page 3 of this letter. The project included in this calculation (LEGOLAND LLC 2025 Project) will use 1.270 acres of equivalent area (see calculations in page 2). Therefore, the remaining equivalent area for Water Quality will reduce to 43.212 acres and the remaining equivalent area for Hydromodification will reduce to 70.217 acres after this project. It must be emphasized that any project after the LEGOLAND Garden Restroom Project must use the remaining amounts highlighted in this letter. The City of Carlsbad and/or the person designated by it must keep track of the remaining equivalent area so that: (a) a proper accountability in time of the remaining equivalent area capacity left after each project is kept so that future LEGOLAND projects are informed, and (b) once the equivalent area amount is either exhausted or no longer usable for any reason future LEGOLAND projects are notified to prepare proper treatment BMPs. Prepared by: Luis Pa ra, PhD, CPSWQ, ToR, D.WRE. R.C.E. 66377 Page 1 of 3 R·E·C WATER QUALITY AND HYDROMODIFICATION EQUIVALENT AREA CALCULATION (1) Project Name: LEGOLAND LLC 2025 (SOP 2023-0012 / CDP 2023-0022 {DEV2023·0061)) (Assigned# for Regional LEGOLAND BMP accountability): Date of (2) Calculation: 6/29/2023 (3) Total Area Impacted: 1.774 acres (4) Existing pervious: 0.628 acres (S) Existing impervious: 1.147 acres (6) Existing self-contained: 0.000 acres (7) Proposed pervious: 0.409 acres (8) Proposed impervious: 1.365 acres (9) Proposed self-contained: 0.000 acres (10) C coefficient (Post-dev.): 0.716 (11) Existing area= proposed area? I YES I (12) Equivalent Area: 1.270 acres Not Including this project, this is the status of treatment for LEGOLAND: (13) Water Quality Equivalent Area: 44.482 acres (14) Hydromodification Eq. Area: 71.487 acres After this project, this will be the remaining treatment for LEGOLANO: (15) Water Quality Equivalent Area: [ 43.212 acres l (16) Hydromodification Eq. Area: ! 70.217 acres Notes: a. Values in blue italics must be provided. Values in bold are calculated. b. (15) and (16) are remaining values after the project and must be used for projects calculated after the date included in this table. c. To REC and CDR knowledge, there have been no other LEGOLANO Projects or adjustments other than those listed in the Sequence of Calculations attached in the next page. Page 2 of 3 R·E·C Sequence of Calculations of Available WQ & HMP Conditions Date: 6/29/2023 Letter Date Project Equiv. Available before Project Available after Project Area (ac) WQ(ac) HMP (ac) WQ(ac) HMP(ac) 6/30/2018 Onginal -0 0 45.766 72.771 11/6/2018 LEGOLAND 2020 1.136 45.766 72.771 44.630 71.635 3/21/2022 LLC-2023 (Hounted House) 0.309 44.630 71.635 44.321 71.326 1/5/2023 LEGOLAND Funtown 0.078 44.321 71.326 44.243 71.248 6/27/2023 Update LLC-2023 removed -0.309 44.243 71.248 44.552 71.557 6/28/2023 Garden Restroom 0.070 44.552 71.557 44.482 71.487 6/29/2023 LLC 2025 1.270 44.482 71.487 43.212 70.217 Page 3 of 3 R·E·C ADDENDUM: LEGOLAND LLC 2025 (DEV2023-0061) 100 YEAR PEAK FLOW ESTIMATE AND COMPARISON WITH REGIONAL BMPASSUMPTION Date: 06/29/2023 SUMMARY On 9/21/2017 REC finished the preparation of a study [1) to determine a relatively large scale 100 year Peak flow analysis for the Regional Drainage Facility at the downstream end of LEGOLAND {adjacent to Palomar Airport Drive). This facility became a Regional Water Quality, Hydromodification and Flood Control Facility for the LEGOLAND property. As a consequence of that study [1], an overall C coefficient, drainage area and time of concentration were determined to insure that the facility could safely convey the occurrence of a 100 year peak flow event. As LEGOLAND keeps updating their property with new projects and rides, t he necessity to assess if t hose new project cause significant increment in the peak flow assumed originally has surfaced, and the City of Carlsbad is requesting an analysis of the 100 year peak flow for the LEGOLAND LLC 2025 project, as the percentage of imperviousness will increase in the area of the project once the project is completed. The purpose of this brief analysis is to demonstrate that the increment of peak flow occurring due to the change in percentage of imperviousness is negligible, and below the level accepted by the City of Carlsbad for LEGOLAND projects (10% increase); thus, there is no need to design a detention facility to reduce the peak to levels equal or lower than those assumed in the 9/21/2017 approved study (1). ASSUMPTIONS • The pre-development C coefficient {C = 0.722) and the pre-development time of concentration (t = 15 min) are taken directly from (1). • Changes in time of concentration are considered negligible as {a) drainage will occur in very similar manner after the development and (b) the time of concentration of the pre-development study is regional in nature, and associated with the time it takes for the entire contributing area to reach the Regional LEGOLAND WQ-Hydromodificatioon-Flood Control facility. • The post development C coefficient is associated with a value of C = 0.9 for impervious area, and C = 0.35 and 0.25 for pervious areas under soil Type D and B respectively, according to the standard values of the County of San Diego Hydrology Manual [2], which were also used in [1). • It will be assumed that soil D will be 20 % of the pervious soil, and soil B the other 80 % of the pervious soil (hence Cperv = 0.27), as those are the approx. overall percentages of perviousness in sub-areas Bl and D1 where the project is located, per the general map of reference [1]. • The 100 year intensity is also obtained from (1), which corresponds with the recommended NOAA intensity, which has not changed since 2016 according to the NOAA web page information (available at (31). Page 1 of 2 R·E·C CALCULATIONS AND RESULTS The peak flow will be obtained per the Rational Method as Q = C-1-A. Contributing Area, pre-development and post-development C coefficients, NOAA intensities (1100, in/hr) and peak flows (0100) are shown in Table 1. TABLE 1. PEAK FLOW ANALYSIS Condition A (ac) %imperv Cperv Cimp C hoo (in/hr) Q100 (cfs) Pre 1.774 . 0.9 0.722 2.67 3.42 Post 1.774 76.94% 0.27 0.9 0.755 2.67 3.58 It can be seen that the peak flow has increased from 3.42 cfs to 3.58 cfs, only 0.16 cfs or 4.5%. CONCLUSION As the C coefficient of the LLC 2025 Project Area is very similar to the assumed C coefficient for this area in the regional analysis (reference (1)), the increase in peak flow observed is only 0.16 cfs, from 3.42 cfs in pre-development conditions to 3.58 cfs in post-development conditions, and this increment is considered negligible, and less than the 10% allowed. REFERENCES [1] "Determination of Pre and Post-Development 100-year Peak Flow". LEGOLANO Regional Biofiltration, Hydromodification and 100-year Detention Facility. REC Consultants, 9/21/2017. SOP 15-26 / DWG 498-2C / GR2017-0025. [2] [3] https://www.sandiegocounty.gov/content/sdc/dpw/flood/hydrologymanual.html San Diego Hydrology Manual. County of https://hdsc.nws.noaa.gov/pfds/pfds map cont.html?bkmrk-ca : NOAA rainfall data web page, where precipitation information is given at a given CA location/ address. Prepared by: Luis Pa ra, PhD, CPSWQ, ToR, D.WRE. R.C.E. 66377 Page 2 of 2 I I EX CURB .,.,., _::~ -- EX BUILDING (NAP) I , EXISTING ATTRACTION ----\ ! EX BUILDING (NAP) \ • J I I \EX 1~'PVC PRlvAIE SO I / l , ... . ,... ........ ' \ ' ~ "·, ,, ~ ;1/;i. / // ;{ , LEGEND: I I AC PAVEMENT I· . ... . 1 CONCRETE I . . .. -: I LANDSCAPE DRAINAGE AREA (DA) BOUNDARY ---DRAINAGE SUB-AREA BOUNDARY PROPERTY LINE CENTERLINE EB DAID DA SIZE (ACRES) +--+--FLOW LINE W/ FLOW DIRECTION EXISTING STORM DRAIN LINE 0 20 40 80 l I ! GRAPHIC SCALE SCALE: 1 "=40' PREPARED FOR: MERLIN ENTERTAINMENTS GROUP US HOLDINGS, A DELAWARE CORPORATION 1 LEGOLAND DRIVE CARLSBAD, CA 92008 CONTACT: TOM STORER TEL: (858) 334-8938 PREPARED BY: COMMERCIAL DEVELOPMENT RESOURCES 695 TOWN CENTER DRIVE #110 COSTA MESA, CA 92626 CONTACT: AARON ALBERTSON, PE TEL: (949) 610·8997 c,, ~ "O 0. 0 :. V c,, 0 C ·5 .... 0 c,, C :::; "' ·;; w _, ,Q .c X w J: "13 J: I '-0 If) N N < c,, 0 0 I... ~ 3-<( 0 "O 0 .0 "' 1: 0 ~ V "' 0 0 0 ~ 0 ~ I 0 z <( _J 0 C, X ~ LANDSCAPE ~ '· AREA o ,~=3.59cfs 1------------------1,n (NAP) " "'-HYDROLOGY EXHIBIT: ~ 1 ; BuiC8iNG ,,, ., . , ::· _;, ' • i----E_x1_s_r _1N_G_o_R_A_1N_A_G_E_M_A_P_ ..... ~ ·-,1 (NAP) ~ ( / LEGOLAND: PROJECT MARS ~ _j 1 1 LEGOLAND DRIVE ·o ~ CARLSBAD, CA 92008 ~ .___ ___ _:;____;;.:;__:__ _______ _____:_ _________ .....::..,__L.:_---'-----'----------_l__--~~..:..:..:___Jl/l I I I I ) EX BUILDING (NAP) EX CONCRETE PATIO (NAP.) 1 //'"!.:-SD -sf--'D .._,. •·» -iD -SD -. SJ -Sll / ,1 / / / / --0 ~ ~ rn f1 0 rn (/) (/) :0 0 t 0 100= i. 77cfs f a ,oo=1.88cls '•~ '---.__ EX 24' CMP TO BE ABANDONED I I _ _j t ~ ~ (0=20.27 CFS) PROP. PROJECT SITE TOTAL: A= 1.65ac, L0100=8. 77cfs PROPOSED • I I BUILDING EX LANDSCAPE AREA (NAP.) r I I I I I I I I I I I 0 • 0 0 • --0 / -·-· 1~-:/>.:.T:. ' ~ I ·.-.;..:ilP'!"'".n!'~ \ :· ··• '·::.,·. ........ - LEGEND: I I AC PAVEMENT I·. •. I CONCRETE I· . ·. · . •. I LANDSCAPE DRAINAGE AREA (DA) BOUNDARY ---DRAINAGE SUB-AREA BOUNDARY ----PROPERTY LINE ---CENTERLINE ® DAID DA SIZE (ACRES) t--t--FLOW LINE W/ FLOW DIRECTION EXISTING STORM DRAIN LINE -~-PROPOSED STORM DRAIN LINE 0 20 ' I 40 GRAPHIC SCALE SCALE: 1"=40' PREPARED FOR: MERLIN ENTERTAINMENTS GROUP 80 US HOLDINGS, A DELAWARE CORPORATION 1 LEGOLAND DRIVE CARLSBAD, CA 92008 CONTACT: TOM STORER TEL: (858) 334-8938 PREPARED BY: COMMERCIAL DEVELOPMENT RESOURCES 695 TOWN CENTER DRIVE #110 COSTA MESA, CA 92626 CONTACT: AARON ALBERTSON, PE TEL: (949) 610-8997 O> J. "CJ ci a :::. Q) □' a C ·5 ... 0 "CJ Q) Ill 0 c.. 0 ... a. I -~ s; X w I <Id I I c:o If) N N < O> 0 e -g_ 3-<( (..) "CJ a .0 Ill .:: 0 ~I 2 II} 0 0 (..) r 0 :::;; I Cl z <( _j 0 0 ljl c:o .------------------ILO HYDROLOGY EXHIBIT: PROPOSED DRAINAGE MAP N N ./ N N 0 1-------------------1~ LEGOLAND: PROJECT MARS ~ -~ 1 LEGOLAND DRIVE o ~ CARLSBAD, CA 92008 ~ IL-------------------------------------------------------------------------------------------------------~ Hydrology Study LEGOLAND California Project 2025 ATTACHMENT 3 Storm Drain Sizing Hydraulic Calculations A. MIN. SD PIPE CALCULATIONS *See Proposed Drainage Mop for Node locations. For full flow in a circular storm drain: 0, = 1.49*(n-1)*(At)*(R/'3)*(S0 112) Where O. = full flow rate (cfs) n = Manning's roughness factor At= (n*02/4) = flow area at full flow (ft2) Rt = (0/4) = hydraulic radius at full flow (ft) S0 = longitudinal slope (ft/ft) SD DATA TABLE· SIZE D (ft) /¼ (ft2) Rt (ft) Cl, •n/(So)l/2 4" PIPE 0.33 0.087 0.083 0.025 6" PIPE 0.50 0.196 0.125 0.073 8" PIPE 0.67 0.349 0.167 0.158 10" PIPE 0.83 0.545 0.208 0.286 12" PIPE 1.00 0.785 0.250 0.464 24" PIPE 2.00 3.142 0.500 2.949 PROPOSED STORM DRAIN LATERALS· Node 1' Node "' S0 (ft/ft) Q 100 (cfs) Material 1.02 1.03 0.010 0.90 HOPE 1.03 1.04 0.134 1.24 HOPE 2.02 2.03 0.081 0.11 HOPE 2.03 2.03 0.020 1.77 HOPE 2.03 2.04 0.010 1.88 HOPE 2.04 2.04 0.020 0.54 HOPE 2.04 2.05 0.010 2.55 HOPE 2.05 2.05 0.020 0.30 HOPE 2.05 2.06 0.010 2.85 HOPE 3.02 3.03 0.011 1.00 HOPE 3.03 3.03 0.020 0.47 HOPE 3.03 3.04 0.010 1.46 HOPE 3.04 3.04 0.020 0.49 HOPE 3.04 3.05 0.010 1.96 HOPE 3.05 3.05 0.020 0.40 HOPE 3.05 3.06 0.010 2.30 HOPE 3.06 3.06 0.010 0.94 HOPE 3.06 3.07 0.010 3.30 HOPE 3.07 3.07 0.020 0.27 HOPE 3.07 3.08 0.010 3.57 HOPE 3.08 3.08 0.010 0.33 HOPE n 0.012 0.012 0.012 0.012 0.012 0.012 0.012 0.012 0.012 0.012 0.012 0.012 0.012 0.012 0.012 0.012 0.012 0.012 0.012 0.012 0.012 PROJECT: Mars ---------LOCAT10 N: Carlsbad, CA DATE: 04/04/2023 For minimum circular pipe size required: D, = (2.16*(n)*(Q)/(S/12))318 Where D, = minimum size pipe required (ft) n = Manning's roughness factor Q = flow rate (cfs) S0 = longitudinal slope (ft/ft) Ave Mannine Rouehness Coefficients for a osed Conduits· Pipe Material PVC HOPE RCP CONC Hn" Value 0.011 0.012 0.013 0.014 D, (ft) d, (in) MIN. PIPE SIZE Qf (ds) CHECK: 0. > Q100 0.58 6.95 8" PIPE 1.31 YES 146% 0.40 4.82 6" PIPE 2.23 YES 180% 0.18 2.14 4" PIPE 0.59 YES 535% 0.66 7.87 8" PIPE 1.86 YES 105% 0.76 9.16 10" PIPE 2.38 YES 127% 0.42 5.04 6" PIPE 0.86 YES 160% 0.86 10.27 12" PIPE 3.87 YES 152% 0.34 4.04 6" PIPE 0.86 YES 287% 0.89 10.71 12" PIPE 3.87 YES 136% 0.59 7.10 8" PIPE 1.38 YES 138% 0.40 4.79 6" PIPE 0.86 YES 183% 0.69 8.34 10" PIPE 2.38 YES 163% 0.41 4.86 6" PIPE 0.86 YES 176% 0.78 9.31 10" PIPE 2.38 YES 121% 0.38 4.50 6" PIPE 0.86 YES 215% 0.82 9.88 10" PIPE 2.38 YES 103% 0.59 7.07 8" PIPE 1.31 YES 140% 0.94 11.32 12" PIPE 3.87 YES 117% 0.32 3.89 4" PIPE 0.29 YES 108% 0.97 11.66 12" PIPE 3.87 YES 108% 0.40 4.77 6" PIPE 0.61 YES 185% Page 1 of 1 B. INLET SIZING CALCULATIONS •see Proposed Drainage Mop for Node locations. Per Section 2.3.2.2 of SDCHDM (20141 for GRATED INLETS IN SAG: [Use LOWER of the two values] jll Capacltv of grate inlet operating as a weir: Q..=C,.xP.xd"' and P.=[l·CJxP Where: O.. = inlet capacity of the grated inlet (cfs) C,. = weir coefficient (constant) P. = effective grate perimeter length (ft) d = flow depth approaching inlet (ft) C,, = clogging factor (constant) 3.33 50% PROJECT:.;.M..;a;;.r;:..s _____ _ LOCATION: Carlsbad, CA DATE: 04/04/2023 121 Capacity of grate inlet operating as an orifice: Oo= Cc,x A_x (2gd)112 and A.= (l ·CJ xA Where: Oo = inlet capacity of the grated inlet (cfs) C,, = orifice coefficient (constant) 0.67 g = gravitational acceleration (ft/s) 32.2 ft/s d = flow depth above inlet, i.e. free board (ft_) __ _ A. = effective (clogged) grate area (ft') c. = area dogging factor (constant) 50% A = actual opening area of the grate inlet (ft-2) __ _ (1) WEIR CONDITION 2) ORIFICE CONDITION USE: minl<l..,, a,.J NODE Q,oo d Inlet Type Size L=W dia. No. Sides p P, Q.. A• A. Oo 0..... CHECK: ldsl lftl lftl lftl w/CU<b lftl lftl ldsl fin21 lft21 ldsl ldsl Q,>Q,_ 1.02 0.45 0.33 Catch Basin 12" X 12" 1.00 -0 4.00 2.00 1.28 50.76 0.176 0.55 0.55 YES 122% 1.02 0.45 0.33 Catch Basin 12" X 12" 1.00 -0 4.00 2.00 1.28 50.76 0.176 0.55 0.55 YES 122% 1.03 0.34 0.17 Catch Basin 12" X 12" 1.00 -0 4.00 2.00 0.45 50.76 0.176 0.39 0.39 YES 114% 1.04 0.33 0.17 Catch Basin 12" X 12" 1.00 -0 4.00 2.00 0.45 50.76 0.176 0.39 0.39 YES 116'1(; 1.04 0.33 0.17 Catch Basin 12" X 12" 1.00 -0 4.00 2.00 0.45 50.76 0.176 0.39 0.39 YES 116% 1.04 0.33 0.17 Catch Basin 12" X 12" 1.00 --0 4.00 2.00 0.45 50.76 0.176 0.39 0.39 YES 116% 2.02 0.11 0.08 Catch Basin 9" x9" 0.75 --0 3.00 1.50 0.12 37.49 0.130 0.20 0.12 YES 109% 2.04 0.14 0.13 Catch Basin 9" X 9" 0.7S --0 3.00 1.50 0.22 37.49 0.130 0.25 0.22 YES 158% 3.02 0.33 0.17 Catch Basin 12" X 12" 1.00 -0 4.00 2.00 0.45 50.76 0.176 0.39 0.39 YES 116% 3.02 0.33 0.17 Catch Basin 12" X 12" 1.00 -0 4.00 2.00 0.45 50.76 0.176 0.39 0.39 YES 116"- 3.02 0.33 0.17 Catch Basin 12" X 12" 1.00 -0 4.00 2.00 0.45 50.76 0.176 0.39 0.39 YES 116% 3.06 0.94 0.33 Catch Basin 24" X 24" 1.00 -0 4.00 2.00 1.28 422.45 1.467 4.55 1.28 YES 136% 3.08 0.33 0.17 Catch Basin 12" X 12" 1.00 -0 4.00 2.00 0.45 50.76 0.176 0.39 0.39 YES 117" •ooen Area fAl aer Manufacturer'$ Catalo.: Size Inlet Type Make/Model Grate A' Equiv. f,me hn-inl Dia.fin) 4 .. Dia. Area Drain NOS #910/917 Flat 5.25 6'" Dia. Area Drain NOS #40/50/60 flat 9.10 6" Dia.A Area Drain NOS #80/81/90 Atrium 28.40 8" Dia. Area Drain NOS #10/20/30 Flat 11.50 9"x 9" Catch Basin NOS #980/990 Flat 37.49 10.16 10" Dia. Area Drain NOS #1040/1050 Flat 21.57 12" Ola. Area Drain NOS #1240/1250 Flat 46.00 12" X 12" Catch Basin NOS #1210/1211 Flat 50.76 13.54 lS"Ola. Area Drain NOS #1511/1512 flat 85.60 18" X 18" Catch Basin NOS #1811/1812 Flat 86.31 20.31 24" X 24" Catch Basin NOS #2415 Flat 422.45 23.45 30" X 30" Catch Basin Old Ca<tle #3030 Flat 490.00 30.28 Page 1 of l Hydrology Study LEGOLAND California Project 2025 ATTACHMENT 4 Water Quality Treatment Letter EQUIVALENT AREA TREATMENT LETTERS AND HYDROLOGY 100 YEAR STORM ADDENDUM LETTERS FOR SOP 16-25 WILL BE SUBMITTED WITH FINAL HYDROLOGY REPORT AS PART OF CONDITIONS FOR GRADING/BUILDING PERMITTING. Hydrology Study LEGOLAND California Project 2025 C~Comln&<cial V <~ ATTACHMENT 5 Referenced Improvement Plans J,U-'1 J>ATE HE]AD ~ ''I 'i CMWD 94-?.Ql • : l z I I f 0 . ~ [ ~ ~ ---- ,----------------------176•------ ,:,6 _______________ ..,,, PflJV.41'£' ROAb ANO urn.,ff"tsc.l'iui."ll.iil,r, ------r-----------.::...:.:_!mo;· ;IIN~A~S~l.£GO 001£: P£R CA~SB•O IWIC,, /,/AP u •oa -i-:~;=~==~==~=:~=:~=:~::~=:---------~==- ► ----- ,~ 12X ---=-==----=-~ ---- t /, ------ --+-• ',~~=====::::::::_-_-_-:._ /66-------,,;s------ ,10------ 172------,,.-----176 ____ _ '--e-__ /_ ----.!c:O()'l)/'4•• £ i rt\ -- , -----/ - / I STORM DRAIN DA TA TABLE LM {)fl TA,IFJEAl'lWG flA/JfUS LCNG1'; liElliARl<'S 17 N25'75"27"£ 1.J.51' 2.-ffCP ,.-18 6177'l r 4~00· #J,/J" 14·~ ,. MM",2'.J7'£ 70.$8' 2,· ~cP ,... 20 N89V9'1J·• 228.42' 2,• P!.C' 21 28TJ9'J6" ,&(/(}' 22.12· 24"/?cP 22 N89~'2fi.lt' 11200· 24-~ h'OlcS I. _.LL LCNCfHS SHOIMV Ali€ 41£,.SI.JRcD ~ INS/OE FACE OF STRUC11.JR£ ro INS/OE FAC,: OF STl?UCTUflc. , I ..... SU roP or CONCl?CTr: BOX All'MltlUJ,I OF f' 8£1..0W F7NISH GRADE" / r- /,/ANHOl.c '7W,lf: ANO COi/CR ~ RMI El.EVA new '"' F'/£(0 Mn! lAIIOSCAF'e SVPCRIN!rNO{NT PRIOI? TO SU/ING FINAL 1'/N ll£VAn()IV /'/Ole: THIS [){TAIL APPUES 10 INN£1? PARK SroRM ()1'AINS ONU' INNER PARK STORM DRAIN CLEANOUTS /,/(} SCA/.£ --~---,,. -~ -._ r-P.:o-1 \!!9.2J;. / / .,,. e '.r-, .... .... I I I I I <. I I I I I _77·11. i: ~1,1-· J II -·\ ~ II r-PM>..:] il: /!. L.!!'V~, .: • I Ii· fl 1 ·< ,IF = -NOO-so·•rw···· : • /: -====1-1 ~;:,c,,;,5~;,,:7=--II 11? f.F' ,r p~-.,,, ;' I fl ,1 ( I -• 11 ,,<iv :•'~~:.~ r-p;.,-1 . IY ~ ,~1-~ la L.!!'~.2.2J ;;; _., r-P--;;0-1 --.;. L~L~J I --~ - --· -JO -:------_-_-_-_-_-_-_-_-_-_-_;~~-----_..,._.s-•• -,:-::sY:;;,'efo~ -r --~~--'.~-< I -~; ~ :• -• • ,. - FOR FUTURE CRANS IN THIS i I .: .. ~ n,-m GRAPHIC~ o .. ·;;.;;;•o.,•,.70,._· .,;.JC'.,-.,-~~ .... ·-.. ".:56..,o·...,.,,,,.,,..90s-· .._..__..120· , .. _ .JO' _.., -· ----------- 27 .-- -+------_-;. 1!>8 -----;..-.. :---;;..-:.-160 -__ _: ~ '7-~ --~~ __ ··:::.. -/-: , I / / RE\'ISION DESCRIPTION o~f~1.;AI 01...::i; ,'PtlRL.,-.fM,. 'AS BUILT ' z.~ DAT( :J -;.v_.;? !NS lDR DATE: I S><~~T I CITY OF CARLSBAD I S><CElS I -., E:NGINELRtNG DtPltRTHENT 47 GRADING P[.A!IS t'OR: LOT'S 18 ond 19 of er 94-09 CARLSBAD RANCH/LEGOLANO CARLSBAD CMWD 94-201 • "' PREPARED BY: UT I LITY S U RVEYO R S , INC . 4395 E. Lowell St Suit G Ontario CA 91761 March 28, 2023 r pr:~ ,r ( r / .1 p-; {. Royce Eklund CDR West ~ WinCan Project Project End Date ~ WinCan X230119_1 3/28/2023 3/28/2023 Page C-1 ~ WinCan Table of Contents Project I I X230119_1 3/28/2023 Section Profile . .. .. .. ... ... .. . .. ...... ... . .. ... ...... .. .. .. . .. .. . ..... ..... . .. . .. . .. .. .. .. ...... ... .. .. .. ... ... .. . .. .... ............ P-1 Section Summary .. . .. .. . .. . .. .. . .. .. . .. ... .. ... .. . . . .... . ... .. .. . . .. .. . . . .. . .. ... .. ... .. ... ... .. . .. .. ... . . . .. ..... .. . .. .. . . . . . . .. P-2 Section: 1; MH 2-MH 1 1 WinCan ................................................................................................................................ 2 Page T-1 ~ WinCan Section Profile Pro1ect I X230119 1 3128/2023 Nr. Upstream Downstream Date Street Media Label Material Total Length MH MH Length Surveyed 1 MH2 MH 1 3/28/2023 One Legoland Dr Corrugated 223.70 223.70 Metal Pipe 1 x Circular 24 = 223.70 Total Length ( 223.70 Length Surveyed) Total: 1 = 223.70 Total Length ( 223.70 Length Surveyed) Page P-1 ~ WinCan Section Summary Project X230119 1 Number of sections Total length of sewer network Inspected length of sewer network Not inspected length of sewer network Total abandoned inspections Number of section inspection photos Number of section inspection videos Number of section inspection scans Number of section inclination measurements Pipe Segment Reference Upstream MH Downstream MH Shape City Street Total Length 1 l 2 3 4 5 Carlsbad One Legoland Or 223.7 Material Distance PACP Code Observation 0 000 AMH Manhole 0 00 MWL Water Level, 0% of the vertical dimension 168.60 TFA Tap Factory Made Active at 2 o'clock, 12inch dim 176.20 TFA Tap Factory Made Active at 12 o'clock, 6inch dim 223 70 AMH Manhole I MH2 MH1 3/28/2023 1 223.70 ft 223.70 ft 0.00 ft 0 0 1 0 0 Circular 24inch Corrugated Metal Pipe Page P-2 WinCan Date: Wor1( Order 3/28/2023 Year laid. Pre-cleaning. No Pre-CleaninQ City: Carlsbad Street: One Legoland Or Location Code: Location Details: Pipe shape: Circular Pipe size: 24 " Pipe material: Corrugated Metal Pipe Lining Method: Additional Info: 1 :1689 Distance Code MH 1 n 0.00 AMH MWL t 168.60 TFA TFA 223.70 AMH u MH2 QSR I QMR I QOR 0000 I 0000 I 0000 Inspection report Weather: Direction: Uostream Drainage Area: Media Label. Flow Control. Sheet Number. Sewer Use: Sewer Calegory: Purpose: Owner. Observation Manhole / MH 1 SEC Surveyed By: Phillip Lagos Pipe Joint Length Water Level, 0% of the vertical dimension Certificate Number: Total Length: 223.7 ' Upstream MH: Up Rim to Invert Downstream MH: Down Rim to Invert: Total gallons used: Joints passed: Joints failed Pipe Segment Ref.: Length Surveyed: 223.7 ' MH 2 0.0 MH 1 0.0 0.0 0 0 Counter Photo Grade 00:00:00 Tap Factory Made Active at 2 o'dock, 121nch dim 00:06:42 Tap Factory Made Active at 12 o'clock, 6inch dim 00:07:16 Manhole / MH 2 00:09:08 SPR I MPR I QPR SPRI I MPRI I OPRI 0.0 I 0.0 I 0.0 0.0 I 0,0 I 0.0 X230119_ 1 // Page: 1 ~ WinCan WinCan Notes: Thank you for choosing to use WinCan to carry out your drainage investigation works. The results and views carried in this report are those of the engineer(s) appointed to carry out the investigation and are considered relevant on the day of the survey. Drain and sewer performance is known to alter over time, so liability cannot be accepted for differences between the recorded data and the actual data at a time after this report was generated. This survey has been created in accordance with the drainage standard used in the country and language settings for this PC. If a DVD has been supplied with this report, please not that it can only be used in a Windows based PC. Please browse the DVD and navigate to the PDF folder to find project-based documents such as drawings, engineer's site notes and survey specifications amongst others. CCTV subsidence investigations do not account for the water tightness of the pipes and are merely a visual inspection of inside of the drains. CCTV drainage engineers are generally not qualified to comment on the causes of subsidence, and can only suggest required remedial actions for the pipes, and not the affected buildings. Subsidence is a building structural failure, which can occur for many reasons. Although drainage failures can contribute to subsidence problems, other causes should always be investigated as part of a considered approach. In order to eliminate drains from suspicion, WinCan suggests that all pipes within at least 1 Om of the subsidence area be pressure tested over and above a CCTV inspection, and remedial suggestions considered based on the findings. Unless otherwise specified in an associated task order (or similar), the data gathered in this report may not be suitable for use as a pre-lining investigation. WinCan are happy to carry out such surveys, but this must be agreed prior to the commencement of the works, and a the client must specify the data they wish to capture and the acceptable tolerances. Where GPS coordinates and heights have been issued within this report, they are to 1 m accuracy, and 2m accuracy for heights. Greater accuracy can be provided on request. 2 ~ WinCan Project Project End Date ~ WinCan 2023_03_28 3/28/2023 3/28/2023 Page C-1 ~ WinCan Table of Contents Project I I 2023 03_28 3128/2023 Section Profile ...................................................................................................................... P-1 Section Summary ... .. . . . .. ... .. . .. . .. .. . . . .. ... ... .. .. . . . . . . . . . .. .. . .... . .. . .. . .... .. . . . ... .. . .. ..... .. . .. ..... . .. .. . .. .. . .. ..... P-2 Section: 1; End of work area-MH 2 .... ... .. . .. .. .. .. ... .. ... ... .. ................. ... .. ... . . .. .. . .. .... . ... .. ... .... ... . 1 VVinCan ................................................................................................................................ 2 Page T-1 ~ WinCan Section Profile Project I 2023 03 28 3/28/2023 Total: 0 = 200.40 Total Length ( 0.00 Length Surveyed) Page P-1 ~ WinCan Section Summary Project I 2023 03 28 3/28/2023 Number of sections 1 Total length of sewer network 200.40 ft Inspected length of sewer network 200.40 ft Not inspected length of sewer network 0.00 ft Total abandoned inspections 1 Number of section inspection photos 0 Number of section inspection videos 1 Number of section inspection scans 0 Number of section inclination measurements 0 Pipe Segment Upstream MH End of work area Reference City Carlsbad Downstream MH MH2 Street One Legcland Dr Shape Circular 24inch Total Length 200.4 Material Corrugated Metal Pipe Distance PACP Code ObseNaticn 1 l 0 0.00 AMH Manhole 2 0.00 MWL Water Level, 0% cf the vertical dimension 3 8.80 TFA Tap Factory Made Active at 12 o'clock, 6inch dim 4 39.00 TBA Tap Break-In Active at 10 o'clock, 12inch dim 5 39.00 TBA Tap Break-In Active at 3 o'clock, 12inch dim 6 62.00 TB Tap Break-In at 12 o'clock, 6inch dim 7 97,60 TBA Tap Break-In Active at 12 o'clock, 6inch dim 8 117.00 TBA Tap Break-In Active at 12 o'clock, 6inch dim 9 127.60 TBA Tap Break-In Active at 12 o'clock, 10inch dim 10 159.00 TBA Tap Break-In Active at 9 o'clock. 8inch dim 11 159.00 TBA Tap Break-In Active at 3 o'clock, 8inch dim 12 200.40 MSA Survey Abandoned Page P-2 ~ WinCan Date: 3128/2023 Year laid: City: Street: Location Code: Location Details: Pipe shape: Pipe size: Pipe material. Lining Method: Additional Info: 1 :1513 MH2 Inspection report Work Order Weather: Surveyed By: Phillip Lagos Pre-cleaning Direction: Pipe Joint Length: No Pre-Cleanina Uastream Carlsbad Drainage Area: One Legoland Or Media Label: Flow Control· Sheet Number: Circular Sewer Use· 24" Sewer Category: SEC Corrugated Metal Pipe Purpose. Owner: Distance Code Observatian AMH Manhole / MH 2 MWL Water Level, 0% of the vertical dimension Certificate Number: Total Length: 200.4 ' Upstream MH· Up Rim to Invert: Downstream MH: Down Rim to Invert. Total gallons used: Joints passed. Joints failed Pipe Segment Ref.: Length Surveyed: 200.4 ' End of work area 0.0 MH 2 0.0 0.0 0 0 Counter Photo Grade 00:00:00 TFA Tap Factory Made Active at 12 o'clock, 6inch dim 00:00:40 TBA Tap Break-In ActJve at 10 o'dock. 12mch dim 00:01:54 TBA Tap Break-In Active at 3 o'clock, 12inch dim 00:02:01 62.00 TB Tap Break-In at 12 o'clock. 6inch dim 00:03:14 t 97.60 TBA Tap Break-In Active at 12 o'dock, 6inch dim 00:04:54 117.00 TBA Tap Break-In Active at 12 o'dock, 6mch dim 00:06:18 127.60 TBA Tap Break-In Active at 12 o'clock, 10inch dim 00:06:49 159.00 TBA Tap Break-In Active at 9 o'clock. 81nch dim 00:08:29 159.00 TBA Tap Break-In Active at 3 o'clock, 8inch dim 00:08:37 200.40 MSA Survey Abandoned I End of work area 00:10:07 QSR QMR QOR SPR MPR QPR SPRI MPRI OPRI 0000 0000 0000 0.0 0.0 0.0 0.0 0.0 00 2023_03_28//Page: 1 ~ WinCan WinCan Notes: Thank you for choosing to use WinCan to carry out your drainage investigation works. The results and views carried in this report are those of the engineer(s) appointed to carry out the investigation and are considered relevant on the day of the survey. Drain and sewer performance is known to alter over time, so liability cannot be accepted for differences between the recorded data and the actual data at a time after this report was generated. This survey has been created in accordance with the drainage standard used in the country and language settings for this PC. If a DVD has been supplied with this report, please not that it can only be used in a Windows based PC. Please browse the DVD and navigate to the PDF folder to find project-based documents such as drawings, engineer's site notes and survey specifications amongst others. CCTV subsidence investigations do not account for the water tightness of the pipes and are merely a visual inspection of inside of the drains. CCTV drainage engineers are generally not qualified to comment on the causes of subsidence, and can only suggest required remedial actions for the pipes, and not the affected buildings. Subsidence is a building structural failure, which can occur for many reasons. Although drainage failures can contribute to subsidence problems, other causes should always be investigated as part of a considered approach. In order to eliminate drains from suspicion, WinCan suggests that all pipes within at least 1 Om of the subsidence area be pressure tested over and above a CCTV inspection, and remedial suggestions considered based on the findings. Unless otherwise specified in an associated task order (or similar), the data gathered in this report may not be suitable for use as a pre-lining investigation. WinCan are happy to carry out such surveys, but this must be agreed prior to the commencement of the works, and a the client must specify the data they wish to capture and the acceptable tolerances. Where GPS coordinates and heights have been issued within this report, they are to 1 m accuracy, and 2m accuracy for heights. Greater accuracy can be provided on request. 2 Locating Area Map(s) AIR X UTILITY SURVEYORS, INC . Legoland Storm Drain (CCTV) ~