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2003-1374 G ENGINEERING SERVICES DEPARTMENT CItyOf Capital Improvement Projects Encinitas District Support Services Field Operations Sand Replenishment/Stormwater Compliance Subdivision Engineering Traffic Engineering J une 24, 2010 Attn: American Contractors Indemnity Company 9841 Airport Blvd., 9"' Floor Los Angeles, California 90045 RE: Nancy Shanahan 866 Bonita Drive APN 258-370-07 Case No. 02-077 Grading permit 1374-G Final release of security Permit 1374-G authorized earthwork, storm drainage, and erosion control, all needed to build the described project. The Field Operations Division has approved the grading and finaled the project. Therefore, full release of the security deposit is merited. Performance Bond 187406, in the amount of$7,052.00, is hereby fully exonerated. The document original is enclosed. Should you have any questions or concerns, please contact Debra Geishart at (760) 633- 2779 or in writing, attention this Department. Sincerely, Debra Geis art ay Lembach Engineering Technician Finance Manager Subdivision Engineering Financial Services Cc: Jay Lembach,Finance Manager Nancy Shanahan Debra Geishart File Enc. TEL 760-633-2600 / FAX 760-633-2627 505 S. Vulcan Avenue, Encinitas, California 92024-3633 TDD 760-633-2700 �� recycled paper CZ O Encinitas March 22, 2006 Charles D. Richmond 2537 Via Pisa Del Mar, CA 92014 Re: Nancy Shanahan Citation #05-1239 866 Bonita Dr. Grading Plan: 1374-G Planning Case: 02-077 Mr. Richmond: Please be advised the subject property was developed by Mrs. Shanahan with the aid of the following professionals: 1. Eaton Development Company 2. Scobba & Associates Consulting — Civil Engineer 3. Barry & Associates— Geotechnical Engineer The Engineer of Record for this project is Christopher L. Scobba and should be able to answer any questions that you may have relating to the subject project and should be your first contact. The City of Encinitas Engineering Department has forwarded this issue to Code Enforcement due to the owners lack of compliance with the subject grading plan and refusal to move forward to satisfy the requirements of the approved plans. The inspector and I are available to meet onsite with you and the Engineer of Record should you so desire; however, I do not wish to meet without the Engineer of Record. Sincerely Greg lids, P.E. Field perations Cc: Peter Cota-Robles, Director of Engineering Services Ron Quigg, Inspector Joan Hughes, Code Enforcement Marianne Buscemi, Code Enforcement T,L 760-633-2600 / FAX 760-633-2627 505 S. Vulcan Avenue, Encinitas, California 92024-3633 TDD 760-633-2700 TJ,,1 recycled paper ENGINEERING SERVICES DEPARTMENT Sy City Of Encinitas Capital Improvement Projects District Support Services Field Operations Sand Rep lenishment/Stormwater Compliance Subdivision Engineering aurae 24, 2010 Traffic Engineering Attn: American Contractors Indemnity Company 9841 Airport Blvd., 9th Floor Los Angeles, California 90045 RE: Nancy Shanahan 866 Bonita Drive APN 258-370-07 Case No. 02-077 Grading permit 1374-G Final release of security Permit 1374-G authorized earthwork, storm drainage, and erosion control, all needed to build the described project. The Field Operations Division has approved the grading and finaled the project. Therefore, full release of the security deposit is merited. Performance Bond 187406, in the amount of$7,052.00, is hereby fully exonerated. The document original is enclosed. Should you have any questions or concerns, please contact Debra Geishart at (760) 633- 2779 or in writing, attention this Department. Sincerely, Debra Geis art �ay Lembach Engineering Technician Finance Manager Subdivision Engineering Financial Services Cc: Jay Lembach, Finance Manager Nancy Shanahan Debra Geishart File Enc. TEL 760-633-2600 / FAX 760-633-2627 505 S. Vulcan Avenue, Encinitas, California 92024-3633 TDD 760-633-2700 �1 r�� recycled paper city or Encinitas March 22, 2006 Charles D. Richmond 2537 Via Pisa Del Mar, CA 92014 Re: Nancy Shanahan Citation #05-1239 866 Bonita Dr. Grading Plan: 1374-G Planning Case: 02-077 Mr. Richmond: Please be advised the subject property was developed by Mrs. Shanahan with the aid of the following professionals: 1. Eaton Development Company 2. Scobba & Associates Consulting — Civil Engineer 3. Barry & Associates — Geotechnical Engineer The Engineer of Record for this project is Christopher L. Scobba and should be able to answer any questions that you may have relating to the subject project and should be your first contact. The City of Encinitas Engineering Department has forwarded this issue to Code Enforcement due to the owners lack of compliance with the subject grading plan and refusal to move forward to satisfy the requirements of the approved plans. The inspector and I are available to meet onsite with you and the Engineer of Record should you so desire; however, I do not wish to meet without the Engineer of Record. Sincerely r Greg Ids, P.E. Field perations Cc: Peter Cota-Robles, Director of Engineering Services Ron Quigg, Inspector Joan Hughes, Code Enforcement Marianne Buscemi, Code Enforcement T�L 760-633-2600 / FAX 760-633-2627 505 S. Vulcan Avenue, Encinitas, California 92024-3633 TDD 760-633-2700 recycled paper Charles D. Richmond Attorney At Law ^ 2537 Via Pisa Del Mar,CA 92014 (858)558-4600 v �S Fax: (858)755-0965 E-mail:cdr @cts.com s March 13, 2006 Attention: Administrative Citations City of Encinitas 505 S. Falcon Avenue Encinitas, California 92024 Re: My Client: Nancy Shanahan Your Citation No.: 05-1239 Subject Property: 366A Bonita Drive, Encinitas California To whom it may concern: This office has been retained by Nancy Shanahan to resolve issues of noncompliance on the above-referenced property. It is her understanding that although no fine was initially levied in the above-referenced citation, that there is now an outstanding fine. This office would like to meet with your department to ascertain what, in the discretion of the inspector, was not compliant. Please contact the above office as soon as possible so we may discuss the resolution of this matter. Sincerely, Charles D. Richmond cc: Nancy Shanahan r CITY OF ENCINITAS - PUNCHLIST 866 BONITA . . Shannahan Residence Inspection date: February 6, 2006 Engineer of Record:Christopher Scobba Phone: 619-379-4227 APN: 258-370-07 Case No.: 02-077 Grading Permit : 1374 GI Issued: 12/11/03 Expired: 6/03/04 Security Deposit: $8,815 50% release: 5-13-04 1. [ etaining Wall-Eastern Property Line. ceow 2. hooks Box-North Property line. c~. 3. [V' PVC- 46 If— ca. 4. E4e eanout— eon 5. 96" PVC — 57 If— co v 6. E� eir Structure— cow 7. [ *' PVC —26 If— &w. 8. [rooks Box-Near Street 9. Swales a. [-]East to West in Rear b. ❑North to South on West Side c. ❑North to South on East Side d. ❑East to West to Brooks Box 10.[jWater Service cojo 11.Q6'' PVC-Weir Structure to CMU Headwall ea.. 12.QeMU Headwall per B/2 13.gFremove PCC Berm a..... 14.(Sewer lateral com 15.❑Redirect Wall Drain to Swale with 90 Elbow 16.❑Repair road to preexisting condition NOTES: A// .�...o�s n,►�� t.ra,.fr Geissler Engineering Corporation 700 Second Street, Suite E Encinitas,Ca 92024 760-633-4252 22 June 2010 Re: As-Built Plans—BMP Certification 866 Bonita Dr. Encinitas, CA 92024 Ref: GEISSLER ENGINEERING CORPORATION Project No. GEC 10-025 The Low Impact Development, Source Control and Treatment Control Best Management Practices as shown on the As-Built Erosion and Sediment Control plan, drawing number 1374-G, were constructed and are operational as required by the Best Management Practice Manual II. Final inspection has demonstrated that the installation of a rock lined drainage swale along the western portion of the property, as well as, the installation of the grass lined swale across the southern portion of the property, conform to the simplified As-Built grading plan and provide infiltration and/or runoff treatment prior to discharge of surface water runoff. Verification by the Engineering Inspector of this fact is done by the Inspector's signature hereon and will not relieve the Engineer of Record or Property Owner of their ultimate responsibility: Engineering Insp for Dated: 1::77 DR-AINAGE REPORT 866 BONITA DRIVE CITY OF ENCINITAS 711 Ak DATE: August 13,2003 e t NA T PREPARED BY: Christopher L. Scobba 17 Horton Plaza, PMB 162 San Diego, CA 92101 PREPARED FOR: EATON DEVELOPMENT CO., INC. 13465 CAMINO CANADA, #106 EL CAJON, CA 92020 QROFESS/O <P-'�&NER S) L(Y'j- R.C.E. No. 61833 * Exp. 06-30—OS ST CIVIL �Q qTF OF CAL�F�R� 8 8/0-r Christopher L.Scobba DATE RCE: 61833 EXPIRES: 6/30/05 ANALYSIS BY:CLS ' CHECKED BY::CLS 03-0003-DRAINAGE.doc i TABLE OF CONTENTS Section Page 1 Sinn n.2 nditions and Background 3 3 onditions 4 Methodology 5 5 ng Analysis................................................................................. 9 6 n Analysis.................................................................................... 12 7 Swale Capacity Analysis................... 8 Detention......................................................................................................... 15 9 Weir and Grate Inlet .................................................................... 16 10 Conclusion......................................... 11 References ......................................... ................................ 20 APPENDIX A—HYDROLOGY DESIGN CHARTS Runoff Coefficients (Rational Method)............................................................ A-1 Rainfall Intensity -Duration - Frequency Curves............................................ A-2 100-Year, 6-Hour Rainfall Isopluvial Map...................................................... A-2 100-Year, 24-Hour Rainfall Isopluvial Map.................................................... A-3 Rational Formula-Overland Time of Flow....................................................... A-4 Nomograph for Determination of Time of Concentration (TJ........................ A-5 For Natural Watersheds 03-0003-DRAINAGE.doc i File: LIST OF FIGURES Fi ure Descrlption Page 1 Vicinity Map....................................................................................................... 1 LIST OF TABLES Table Description Page 1 Existing Conditions Hydrology Calculations................................................... 8 2 Developed Condition Hydrology Calculations................................................. 8 3 Hydraulic Calculations-Pipe Flow.................................................................... 11 4 Riprap Calculations Summary.......................................................................... 12 5 Hydraulic Calculations-Grass Swale................................................................ 14 6 Hydraulic Calculations- Grate Inlet Weir......................................................... 17 7 Hydraulic Calculations- Grate Inlet Orifice..................................................... 18 ATTACHMENTS Exhibit A Drainage Area Map—Developed Conditions Exhibit B Drainage Area Map—Existing Conditions 03-0003-DRAINAGE.doc 11 OCq TjON CQ O � V Q m O MEL BA RD. SANTA FE DR. V/CIIVI T Y MAP NO SCALE THOMAS BROS. 1147—E7 Figure 1. Vicinity Map (No Scale) 03-0003-DRAINAOE.doc 1 SECTION 1 INTRODUCTION This drainage report has been prepared to document the hydrology analysis for the storm drain systems associated with the grading plan for 866 Bonita Drive in and is based upon topographic information obtained from 1"=200' County maps. This development is located in Encinitas California within the Batiquitos sub-basin of the Carlsbad watershed. The objective of this drainage report is to determine detention, storm drainpipe, swales, and catch basin sizing requirements under developed conditions to carry a required 100-year frequency storm. 03-0003-DRAMAGE.doc 2 SECTION 2 EXISTING CONDITIONS AND BACKGROUND Existing conditions for 866 Bonita Drive consist of southwesterly gently sloping terrain at an average of approximately 3%. The existing on-site drainage can be characterized by natural overland flows that are ultimately conveyed to an existing 12"PVC storm drain outside and parallel to the southwesterly property boundary of the panhandle portion of APN 258-370-08. The outlet point of this existing storm.drain is unknown according to Masih Maher with the City of Encinitas. Offsite drainage contributions to the existing topography consists of approximately 0.11 acres of contributory area that is conveyed to a local depression located near the midpoint of the northerly property boundary and appears to ultimately drain via surface flow across the proposed project. According to Masih Maher from the City of Encinitas there has been a historic drainage problem in the area adjacent to the proposed project. The main impacts of concern are related to the existing local depression that is positioned at the midpoint of the northerly property line and nuisance drainage that is discharged from an existing 4"drain from the back of an existing retaining wall on the adjacent property to the east. Due to these existing problems detention to existing conditions is required. The existing drainage basin/sub-basin layout and the associated storm drainage system are shown on Exhibit `B' (see attachments). 03-0003-DMINAGE.dm 3 SECTION 3 DEVELOPED CONDITIONS The proposed condition for the project does not represent a significant deviation from that of existing condition. There will be no diversion of flow and the existing flow regime will be modeled with a graded pad tipped at approximately 2% and graded to an average slope of 3%, consistent with the existing southwesterly gently sloping terrain. The proposed drainage regime is characterized by overland flows that ultimately drain to an existing 12"PVC storm drain outside and parallel to the southwesterly property boundary of the panhandle portion of APN 258-370-08. Offsite drainage contributions to the proposed project are required to be conveyed via sub- surface drainage improvements as part of this analysis. Per an on-site meeting with Masih Maher from the City of Encinitas, these flows will not be subject to detention requirements. Offsite contributions conveyed to this low point will be conveyed to the downstream side of a proposed "V-Shaped"weir structure via a proposed 6"PVC drainpipe. The proposed weir is intended to attenuate peak flows, due to runoff generated on-site to existing condition levels, and will discharge to a proposed grated inlet and subsequent 2-6"PVC outlets that will then connect to a proposed grate inlet intended to mitigate potential storm water quality and hydraulic issues at the inlet to the existing 12"PVC storm drain. The proposed drainage basin layout and the associated storm drainage system are shown on Exhibit `A' (see attachments). 03-0003-DRAMAGE.doc 4 SECTION 4 HYDROLOGY METHODOLOGIES This drainage system has been designed in general conformance with the County of San Diego Hydrology Manual. Drainage basins are less than 0.5 square mile; therefore, the Rational method is utilized to calculate storm runoff. The underground storm drain system is designed to convey the 100-year-frequency storm water. Pipes are sized to be free of pressurized flow. The runoff and drainage system will be comprised of mainly overland flow to grass lined bladed drainage swales with rip-rap energy dissipaters that ultimately flow to a proposed V-shaped weir structure and subsequently to the existing 12"PVC storm drain at the southwesterly corner of the panhandle portion of APN 258-370-08 va 2-6"PVC drains. The hydrological analysis utilized to determine the runoff at each design point was the Rational Method(Q= C x 1 x A). The following pages describe the methods used to determine each component of the Rational Method equation, in which Q =Runoff(CFS), C =Runoff coefficient, 1A =Rainfall intensity (in/hr), and A =Area(acres). Determination of Runoff Coefficient Runoff coefficients are dependent on the proposed land use of the basin. Coefficients for this project were obtained from the County of San Diego Hydrology Manual—Table 3-1 (see Appendix A-1). Medium Density Residential (10.9 DU/A or less) and Soil Group D have been conservatively assumed for this area. Based on these criteria, a runoff coefficient of 0.60 will be utilized for this analysis. Determination of Intensity Rainfall intensity(1) is based on the "Intensity-Duration-Design Chart-Template" curves in the County of San Diego Hydrology Manual, Figure 3-2 (see Appendix A-2). 03-0003-DRAINAGE.doe 5 _........... . Time of Concentration Time of concentration is the time required for runoff to flow from the most remote part of the watershed to the outlet point or design point under consideration. The time of concentration(T,) at any point within the drainage area is given by: T,= T,+ Tr, Where T; =Inlet time and T, =Travel time. Inlet time is broken down into two components: overland time (To) and gutter time (Tg): T,= Ta+ Tg; Therefore, T,= To+ Tg+ Tr, The following paragraphs further define the individual components of the time of concentration and the methods used to quantify those components. Overland Time (T„) Overland time is the period required for runoff to travel from the farthest edge of a drainage basin to the street gutter. The method of determining overland time is dependent on the type of watershed. For natural watersheds, overland time is determined using the Appendix A-3.1 (taken from the San Diego County Design Manual). Gutter Time (T,,) The gutter time is determined by assuming an initial time of concentration, T;(may use To for the parkway or a lot) and calculating an initial Q;. To determine the velocity in the gutter, divide Q; by 2 to obtain an average flow. Use this average flow with the graph in the Appendix to determine an average velocity, V, for this gutter length,L. Tg=Ll(V x 60). 03-0003-DRAINAGE.doc 6 Add this gutter time to To to obtain a new time of concentration, T,. Use this new T,to calculate a new Q12 and determine a new VQ,,e, in order to calculate a new Tg. Repeat procedure until assumed T,= To+ Tg. Travel Time W Travel time is considered between the nodes of a flood-routed system. Travel time is calculated by using the following formula: Where: T, _ L . 1 min — V 60sec Tt= Travel Time V=Velocity of flow(ft/sec) L =Flow length(feet) Flood routing will not be utilized for this project due to a uniform time of concentration. Gutter flow will not be utilized with this project. Determination of Areas The area(A) of each drainage basin was determined from the Drainage Area Map. See the Existing and Developed Drainage Basin Exhibits. Hydrology Calculations The existing condition of the project site is undeveloped. All runoff is natural overland flow, which is concentrated and conveyed to an existing storm drain. Therefore, the predevelopment hydrology calculation is based on the assumption that the whole on-site drainage area is one basin with natural overland flow. The calculations are shown in Table 1. The hydrology calculations for the developed condition are shown in Table 2. Each basin is identified relative to the drainage feature used to collect runoff from it. Basin areas, C-factors, lengths of flow paths, slopes of flow paths, times of concentration, intensities, and total flows are also listed. 03-0003-DRA[NAGE.doc 7 Flood RoutinLy Method The Modified Rational Method was utilized to calculate peak storm water flows and route the calculated flows through the drainage system. When two major basins combine at a junction point, the smaller of the flows is adjusted using the Modified Rational Method. This procedure accounts for the differing times of concentration for the flows upstream of the junction point. The smaller Q is reduced by either the ratio of the intensities or the ratio of the times of concentration, according to the following procedure: • Let Q, T, and I correspond to the tributary with the largest discharge. • Let q, t, and i correspond to the tributary with the smallest discharge. • Let Q and T correspond to the peak discharge and the time of concentration when peak flow occurs. If T> t, the peak discharge is corrected by the ratio of the intensities: Q= Q+q(Pi) and T= T. If T<t, the peak discharge is corrected by the ratio of the times of concentration: Q = Q.+q(T/t) and T= T. Given the small basin sizes and assumed uniform time of concentration flood routing will not be necessary. Pine Flow Travel time has been considered between the nodes of the flood-routed system. Travel time is calculated by using the following formula: Travel Time=L/(V x 60), Where 03-0003-DRAINAGE.doc 8 L =Pipe length(feet) and V=Velocity of flow in pipe(ft/sec). Flood routing will not be utilized for this project due to a relatively uniform time of concentration. 03-0003•DRAINAGE.doc 9 Table 1. Existing Condition Hydrology Calculations Surface Runoff for 100-Year/6-Hour Storm DRAINAGE CALCS-EXISTING CONDITION BONITA DRIVE-EXHIBIT'B' BASIN FROM TO D H S P6 P24 P6/P24 T c 150 A C Ql NAME NODE NODE ft ft % in in min in/hr ac cfs A Al A2 330 19 5.760/. 2.5 4.25 0.59 11.9 3.8 0.27 0.45 0.46 Table 2. Developed Condition Hydrology Calculations Surface Runoff for 100-Year/6-Hour Storm DRAINAGE CALCS-PROPOSED CONDITION HYDROLOGY BASIN FROM TO S P6 P24 P6/P24 T c I A �� C Qloo COMMENT NAME NODE NODE % in in min in/hr ac cfs 1 2 .38% .5 .25 .59 .2 5.2 .11 .6 .34 1 2 .78% 5 25 .59 .7 5.5 .16 .6 .53 1 2 5.94% .5 .25 .59 .9 .5 03-0003-DRAINAGE.doc 10 SECTION 5 PIPE HYDRAULIC CALCULATIONS The storm drainpipes for the proposed systems were designed based on Manning's equation: 1.49 2 I Q= ,q.(R)3Sz ! Do n Where: n =Roughness coefficient. ----- -- --------______ _ -_ R=Hydraulic radius (ft). e R - (A)P do A =Cross-sectional area of flow A = 1 .(9-SIN(B))•Do 2 P = Wetted perimeter(ft). P=-•(0)•Do S = Slope of culvert (ft/ft). Table 3. Proposed Condition Hydraulic Calculations Storm Drain DRAINAGE CALCS-PROPOSED CONDITION HYDRAULICS-STORM DRAIN BASIN FROM TO LP;a AH S d° 0 D A [ ]P[ft] P'� n QMAx QI00 COMMENT NAME ODE NODE ft ft % ft rad in s cfs cfs A Al A2 48.4 0.40 0.83% 0.30 3.53 0.9 6.0 0.12 0.013 0.61 0.34 OK A A2 A3 56.4 0.4 0.77% 0.47 5.28 1.3 E6.0 0.19 0.013 0.44 0.53 PIPE IS AT CAPACITY C A3 C1 23.5 0.40 1.70% 0.46 5.14 1.3 0.19 0.013 0.79 1.50 2 0.79>1.S�OK 03-0003-DRAINAGEAd 11 SECTION 6 OUTLET DESIGN ANALYSIS Riprap rock class and apron thickness are determined in accordance with the Standard SDecification for Public Works Construction, dated 1997 . The riprap apron width and length are based on the San Diego Regional Standard Drawing No. D-40. Riprap calculations are summarized in Table 4 below: Table 4. Riprap Calculations Summary Channel Median Stone Apron Location Dimensions Flow Velocity Rock (Size D50) (inches) (cfs) (fps) Class (feet) Width Length (feet) (feet) Strom Drain Outlet 6"X36" 0.53 2 .25 Ton 2$ 3 3 03-0003-DRAINAGE.doc 12 SECTION 7 SWALE CAPACITY CALCULATIONS The swales along the western and southern portions of the site are to collect overland storm water from the site, and carry it into to the detention basin and underground drainage system. (MIN) '�I=1 11—III_ III-1 11=1 I I=f I I=1 11=1 I III=III=II PEI II—III=III- I 11=1 I I 7E1 11=1 1—''-11 1=l I 111—III— z II!—II1-111 =I I Il i 11 l li do i 111 IE 1 111111j11' —b Capacity of Swale Maximum Capacity: 2 1 Q_ 1.49A.(R)3S2 n Where: A R — P) A = 2 (b+z•dj(dj P=b+2 d,, +(z d,, And d„ = Depth of water=0.5 feet(when carrying Qm,,,.,) b .= Width of channel base=0 feet S = 0.0108 Z = slope ratio n = Manning roughness coefficient=0.06. Q=(1.49/0.06)(0.31)(0.14)" (1.8) 112= 1.3 CFS. The peak discharge collected by the swale will be attributed to in Basin B is Qloo= 0.53 CFS, which is less than 1.3 CFS, therefore, the swale sizes are appropriate. 03-0003-DRAINAGE.doc 13 Table 5. Proposed Condition Hydraulic Calculations Storm Drain DRAINAGE CALCS-PROPOSED CONDITION HYDRAULICS-DRAINAGE SWALE BASIN FROM TO LCHANNEL OH S d„ b p A V100 QMAx Qioo COMMENT NAME NODE NODE in in % in [in) z [in] ° s s cfs cfs B BI B2 122.0 2.20 1.80%0.28 0.00 4.00 2.30 0.31 0.060 1.7 1.30 0.53 n for 2"grass swale 03-0003-DMINAGE.doc 14 SECTION 8 DETENTION Detention Requirements Linear hydrographs will be used given the small basin size subject to detention requirements. The increase from existing to proposed runoff volumes will be detained within the proposed drainage swale that parallels the western boundary of the proposed project. Riprap protection is provided at all outlets to minimize potential for erosion in these areas in an effort to mitigate storm water quality issues. A time of concentration of 7.9 min and peak discharge of 0.3 CFS corresponds to a total volume of 142 CF for proposed conditions. A time of concentration of 8.5 min and peak discharge of 0.23 CFS corresponds to a total volume of 117 CF for proposed conditions. The total storage requirement for this project is 142-117=25 CFS. This can be accommodated with the proposed channel at the proposed maximum flow depth of 6"and an average slope of 1.8% of length L=37.3' which is less that the available swale length of 60'. 03-0003-DRAfNAGE.doc 15 SECTION 9 WEIR AND GRATE INLET CAPACITY CALCULATIONS Capacity of Weir Grate Inlets For `V' Shaped weirs with a 100°angle can be approximated by the equation: $ l 9 s Q= Cz ' 15 J TAN(— H z l2) Where, C2 =0.58 (conservative estimate) 0= 100° H=depth of now(ft) When set to the existing condition flow rate of 0.79 CFS this corresponds to a flow depth of 0.5 ft in depth from the crest of the weir. A grate inlet in sag configuration operates in weir flow at low ponding depths. A transition to orifice flow begins as the ponded depth increases. The governing equation for grate inlet weir flow is; Qw = Cw P h1.5 where: QW=weir capacity of grate (cfs) CW=weir coefficient=3 P=perimeter of the grate(ft.) as shown in Figure 8-1: A multiplier of about 0.5 is applied to the measured perimeter as a safety factor. h =allowable head on grate(ft.) 03-0003-DRAINAG E.doc 16 Figure 8-1 CURB r----- W �----L-� P--2(W - width of bars) +L (kith curb) P=2(W+L -bars) (without curb) A=WL - area of bars Table 6. Proposed Condition Hydraulic Calculations Grate Inlet Weir DRAINAGE CALCS-PROPOSED CONDITION HYDRAULICS-WEIR FLOW BASIN FROM TO CW W L BARS P h Qw NAME NODE NODE (ft) (ft) COMMENT B (ft) ft ft cfs B1 B2 3.0 1.0 1.0 0.5 3.00 0.50 3.18 Capacity of Orifice Grate Inlets Q. = Co A 42 gh where: Qo=orifice capacity of grate (cfs) Co=orifice flow coefficient= 0.67 A= clear opening area(sq. ft.) of the grate (the total area available for flow). A multiplier of about 0.5 is applied to the measured area as a safety factor. g=acceleration due to gravity (32.2 ft/s2) 03-0003-DRAINAGE.doc 17 h=allowable head on grate(ft.) A comparison is made between calculated capacities from weir and orifice calculations and the lower value is chosen as the design capacity. The design capacity of a grated inlet in sag is based on the minimum flow calculated from weir and orifice conditions. Figure 9-2 demonstrates the relationship between weir and orifice flow. If Qo is greater than QW (to the left of the intersection in Figure 9-2), then the capacity calculated with the weir equation is used. If, however, Qo is less than QW (to the right of the intersection), then the capacity as determined with the orifice equation would be used. Figure 9-2 Weir(Q.-h1.3 a Orifice(Q«h0.3 / r ' eu Orifice C ontrol C of r of EtTective Head(10 Table 7. Proposed Condition Hydraulic Calculations Grate Inlet Weir DRAINAGE CALCS-PROPOSED CONDITION HYDRAULICS-ORIFICE FLOW 866 BONITA DRIVE GRADING PLAN-MAP-EXHIBIT'A' BASIN FROM TO Co A h Qo NAME NODE NODE s ft cfs COMMENT B B1 B2 0.7 0.50 0.50 1.901 0< W< ACTUAL SO Q,GOVERNS AND IS ADEQUATE Qo is greater that the runoff generated from runoff due to the proposed project. 03-0003-DRAfNAGE.doc 18 SECTION 10 CONCLUSION The analysis presented above has shown that the proposed drainage improvements are ad to convey a 100-year storm. A conservative approach was taken for several components of analysis; Swale and detention analysis assumed that the entire lot will drain through quate grass lined Swale adjacent and parallel to the westerly roe this ugh the proposed Portion will be conveyed via the proposed Swale that utlets o he grate inlet at the easterly cant of the proposed driveway which will contribute to the detention capacity of the drainage improvements. side g 03-M3•DR.MNAGE.doc 19 SECTION 10 REFERENCES • Standards for Design and Construction of Public Works Improvements in the City of Carlsbad, dated April 1993. • County of San Diego, Department of Public Works Flood Control Design: H drol0 Manual, October 1973, revised September 2001. T- • City of San Diego: Drainage Design Manual, April 1984, revised March 1989. 03-0003_p RA I NAG E.doc 20 APPENDIX A HYDROLOGY DESIGN CHARTS 03-0003-DRAINAG E.doc 0 t!7 r• I'D O\ N t— O M O� O� N Vl V') �!1 'j 'cr ,I: I,-! � � [- Q M o 0 0 0 0 0 0 00 ,. g r-+ i N 3 O \.D N in 00 rn 00 00 co U M M In W) �O �D (� l� 00 00 00 c� p, O O O O O O O O O O O O O O O N .�. 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I p Z QCL W- ]F— � pz z t-- Q O � �W W U m m I> (M W z � = Z 20 W Z ME w �- Cl w z T Q W w o co cn z 1 Q m(n CL O Q O -j O = �i O z o m >G Q W Z Z Z U W OCL W O j IOD m Q Q V) cr— CL Z OD m Q m � C.. �] m N N CL t� O H 4 LQ J v E30NITA z o � Q o N O O Z U LLJ -320 m 0 W ga-a� -�qz Z U i Q Q m O - 1 ur S ,f2 cl trti 9� M F R LLI Z U V) m Q ry� rr^^ Q m N W W O I U N o �a-a��g�z a Z Z 2.0 v G a 0 ca W a Z W w Q-1 U Z F- oD l- _ �W W Z Q J z ° Q W � � m c3i) V = Q mZ °o o Q m o > �/ z o J< 0 o = z z Z a OHO W w m m ¢ & z Q cn � � QmU) � W z�� o v DRIVE B ON I TA o Q o N O O -320-- I � o m O ur i -311 s d A _ r (n O d O to _ e N O /T- N 500 70 y N h \ 4° h 400 60 w w LL Z_ w 300 50 Q O i Cn O ^O w Ui F- OV 200 40 Z LU i Q G' O M 3 G Oa F- 0 h� LL 100 GAO 30 g OOF .060 j G O 1 G,o�o 0 A 10010 20 C,08o C.0•g0 0.095 10 0 EXAMPLE: Given: Watercourse Distance(D)=250 Feet Slope(s)=0.5% T=1.8(1.1-C) VD— Runoff Coefficient(C)=0.70 3VS- Overland Flow Time(T)=14.3 Minutes Y$ SOURCE:Airport Drainage,Federal Aviation Administration, 1965 - F I G U R E Rational Formula-Overland Time of Flow Nomograph A 3-5 5 -s HazMat/County Hydrogeology Manual/Overland Flow.FH8 -07 BARRY AND ASSOCIATES GEOTECHNICAL ENGINEERING P.O. Box 230348 Encinitas, CA 92023-0348 (760) 753-9940 November 6 , 1998 Nancy Shanahan 324 La Vita Ave . Encinitas , California 92024 ( c Subject: ROUGH GRADING REPORT a 1� Proposed Single Family Residence Bonita Drives, Encinitas , California 92024 A. P .N. 258-370-07 ENGINEER!� �N�ASg G�ZY OF E Reference: PRELIMINARY GEOTECHNICAL INVESTIGATION Proposed Single Family Residence - Bonita Drive Encinitas , California 92024 A. P .N. 258-370-07 Dear Ms . Shanahan, - In response to your request, we have observed the grading operation and performed field density tests for the proposed residence on the above referenced property. The results of our density testing and laboratory testing are presented in this report. -- Based on the results of our testing, it is our opinion that the fill was placed in an adequate manner and compacted to a minimum of 90 percent of the laboratory maximum dry density. - If you have any questions , please contact us at 760 . 753 . 9940 . This opportunity to be of service is appreciated. w Respectfully submitted, A. R. BARRY ND ASSOCIAT QitOfESSj� . R. B r l_ Principal Engi eer 000119 '� w EIP• 3/31102 KCAL ROUGH GRADING REPORT Proposed Single Family Residence Bonita Drive Encinitas —California 92024 A. P .N. 258-370-07 Prepared for Nancy Shanahan 324 La Vdta Ave . Encinitas , California 92024 _ November 6 , 1998 W.O. G- 1537 Prepared by: BARRY AND ASSOCIATES _ P . O_ Box 230348 Encinitas , California 92023-0348 November 6 , 1998 W, O. # G-1537 Page 1 INTRODUCTION This report presents the results of our observations and field - density testing of the grading project for the proposed residence. The project consisted of removing approximately 2 feet of loose sur. ficial soil and re-compacting. The results of our density testing are presented on. Table 1 . -- LABORATORY TEST DATA The laboratory standard for determining the maximum dry density was performed in accordance with ASTM D 1557-92 . Field density tests were performed in accordance with ASTM D 1556 . The results of the laboratory maximum dry density, for the soil used as compacted fill - on the site , is summarized below: Maximum Dry Density Optimum Description (p.c . f . ) Moisture (o) Brown silty sand 119. 0 11 . 0 EXPANSIVE SOILS Pad grade soils have an expansion potential in the low range. DISCUSSION The following is a discussion of the grading operations , as they were performed on the site : 1 . Approximately 2 feet of loose soil was removed from one half the November 6 , 1998 W. O. # G-1537 Page 2 lot and stockpiled on the other half. The bottom of the excavation was probed with a steel probe and determined to be adequate . 2 . Fill soil was placed in lifts of approximately 6 . 0 to 8 . 0 inches thick. 3 . The soil was moistened as required to achieve optimum moisture content, and compacted with track mounted earth moving equipment. 4 . The fill was placed to a minimum of 90 percent of the maximum dry density, as indicated by our test results . 5 . Removal and recompaction included the area 5 ' outside the building line . INSPECTIONS All structural footings excavations should be inspected by an engineer prior to setting reinforcing steel . LIMITATIONS This firm assumes no responsibility for any alterations made without our knowledge and written approval to the slope or pad grade on the lot, subsequent to the issuance of this report. November 6 , 1998 W.O. # G-1537 Page 3 If you have any questions , please contact us at (760) 753-9940 . This opportunity to be of service is greatly appreciated. Respectfully submitted, - A. R. BAR AND ASSOC '0 ax & I R. A. R. Bar y 000119 Principal Engine r a Exp. 3131/02 �'� 0)ECM%k �' OPC W. O. # G-1537 Bonita Drive Encinitas , CA APPENDIX "A" LABORATORY TEST RESULTS TABLE I Field Dry Density and Moisture Content Moisture Dry Relative Test Test Content Density o No. Location Elev._ cf Compaction 1 House pad grade -2 ' 13 . 2 109 . 5 92 2 House Pad grade-1 14 . 0 110. 7 93 3 House Pad grade 13 . 0 109 . 5 92 BARRY AND ASSOCIATES GEOTECHNICAL ENGINEERING P.O. Box 230348 ' Encinitas, CA 92023-0348 August 19, 2002 (760) 753-9940 r Nancy G. Shanahan 348 La Mesa Avenue _ Encinitas, California 92024 Subject: UPDATED PRELIMINARY GEOTECHNICAL INVESTIGATION Proposed Single Family Residence Bonita Drive Encinitas, California 92024 A.P.N. 258-370-07-00 References : PLANS PREPARED BY ROY JOHNSON OF LA MESA, CALIFORNIA Dated 6/24/02 PRELIMINARY GEOTECHNICAL INVESTIGATION Proposed Single Family Residence Bonita Drive Encinitas, California 92024 - A.P.N. 258-370-07 Prepared by Barry and Associates, Dated 11/7/97 Dear Ms . Shanahan, In response to your request, we have reviewed the referenced report in regards to the development of the referenced property. This updated evaluation is based on a site inspection and review of the referenced plans and geotechnical report. - From a geotechnical point of view, it is our opinion that the site is suitable for the proposed project, provided the recommendations in this report are implemented during the design and construction - phase. If you have any questions, please contact us at (760) 753-9940 . Respectfully submitte A.R. BAR Y AS SO �Q SS/n R. A.R. a ry, w 000116 m Principal Engin• Exp. 3/31/06 TECHN�GP��Q- C OFCALW August 19, 2002 W.O.#P-1537-1 Page 2 SITE CONDITIONS Based on a visual inspection of the subject property and the adjacent properties, the site conditions remain essentially the same since the time of the referenced preliminary geotechnical investigation. PROPOSED DEVELOPMENT Plans for the project were prepared by Roy Johnson, Architect, of La Mesa, California. The plans provide for a two story residence and accessory dwelling unit. CONCLUSIONS AND RECOMMENDATIONS General Based on our review, the recommendations presented in the referenced report are compatible with the geotechnical conditions on the site. Seismic The review of available geologic maps including Maps of Known Active Faults Near-Source Zones in California and Adjacent Portions of Nevada published by ICBO (1998) indicate that the nearest active fault is the Rose Canyon Fault located approximately 5 .5 kilometers south west of the subject site. The Rose Canyon Fault is a class B fault capable of generating a magnitude 6 .9 earthquake. The August 19, 2002 W.O. #P-1537-1 Page 3 following seismic factors are in accordance with the 1997 Uniform Building Code. Parameter Table Symbol Factor Seismic Zone Factor 16-I Z 0 .4 Soil Profile Type 16-J - SD Seismic Coefficient 16-Q Ca 0 .44Na Seismic Coefficient 16-R Cv 0 .64Nv Near Source Factor 16-S Na 1. 0 Near Source Factor 16-T Nv 1. 18 Seismic Source Type - B Maximum Moment Magnitude. . . . . . . . . .6.9 Slip Rate, SR. . . . . . . . . . . . . . . . . . . . .1. 5 mm/yr. Lictuefaction In accordance with reference #4 (Planning Scenario For A Major Earthquake, San Diego-Tijuana Metropolitan Area, published by the California Department of Conservation, Division of Mines and Geology) the site is not located in an area of seismically induced liquefaction. The soils on the site are not considered subject to seismically induced liquefaction based on such factors as soil density, soil type, and lack of groundwater. August 19, 2002 W.O. #P-1537-1 Page 4 Foundation Footings for the proposed structure should be a minimum of 15" wide and founded a minimum of 18" below grade. Footings founded a minimum of 18" below grade may be designed for a bearing value of 1500 psf . The bearing values indicated above are for the total of dead and applied live loads. These values may be increased by 33 percent for short durations of loading, including the effects of wind and seismic forces . Resistance to lateral load will be provided by friction acting at the base of foundations and passive earth pressure. A coefficient of friction of 0 .35 should be used with dead-load forces . A passive earth pressure of 250 pounds per square foot, per foot of depth of fill penetrated to a maximum of 1500 pounds should be used in the design. Minimum requirements for reinforcing steel should be 2-#5 bars, 1 placed 3" from the bottom of the footing and 1 placed 1. 5" below the top of the footing. August 19, 2002 W.O.#P-1537-1 Page 5 Slabs on Grade Slab on grade should be a minimum of 4 inches thick and reinforced in both directions with No. 3 bars, placed 18 inches on center. The slab should be underlain by a minimum 4-inch sand blanket which incorporates a minimum 6 .0-mil Visqueen or equivalent moisture barrier in its center, for moisture sensitive floors . Utility trenches underlying the slab should be bedded in clean sand to at least one foot above the top of the conduit, then backfilled with the on-site granular materials, compacted to a minimum of 90 percent of the laboratory maximum dry density. However, sufficiently compacting the backfill deposits may damage or break shallow utility lines . Therefore, minor settlement of the backf ill in the trenches is anticipated in these shallow areas . To reduce the possibility of cracks occurring, the slab should be provided with additional reinforcement to bridge the trenches . Footincr Inspections Structural footing excavations should be inspected by a representative of this firm prior to the placement of reinforcing steel . Plan Review We have reviewed the preliminary geotechnical report, foundation plan, details and specifications for the proposed residence. The plans incorporate the minimum recommendations presented in the above referenced report. August 19, 2002 W.O. #P-1537-1 Page 6 All of the applicable minimum recommendations presented in the preliminary geotechnical report should be implemented during the construction phase. Should any unforeseen geotechnical conditions be encountered during construction, additional recommendations may be necessary at that time. LIMITATIONS This report is presented with the provision that it is the responsibility of the owner or the owner' s representative to bring the information and recommendations given herein to the attention of the project' s architects and/or engineers so that they may be incorporated into the plans . If conditions encountered during construction appear to differ from those described in this report, our office should be notified so that we may consider whether or not modifications are needed. No responsibility for construction compliance with design concepts, specifications or recommendations given in this report is assumed unless on-site review is performed during construction. The conclusions and recommendations of this report apply as of the current date. In time, however, changes can occur on a property whether caused by acts of man or nature on this or adjoining properties . August 19, 2002 W.O.#P-1537-1 Page 7 Additionally, changes in professional standards may be brought about by legislation or the expansion of knowledge, consequently, the conclusions and recommendations of this report may be rendered wholly or partially invalid by events beyond our control. This report is therefore subject to review and should not be relied upon after the passage of three years . The professional judgments presented herein are founded partly on our assessment of the technical data gathered, partly on our understanding of the proposed construction and partly on our general experience in the geotechnical field. If you have any questions, please call us at (760) 753-9940 . Respectfully submitted, A.R. BARRY AS SOC I Q FESSIn (7Y ��O��Z R. y G00119 � y A.R. Barry, P.E. LU m Principal Engi er °f- Ezp. 3/31/06 ECNN�GP �Q q�OFOAUE�� `c O O 7 "r ' �.-9° :•�:i� g° „"-�. 'f i ,'1` mac''`' --_ i1_ az c P it lei 5 Ila 411 7- jag i-b"3� � � �c � � � QS° ¢ is g• Y � � -. 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Box 230348 Encinitas, CA 92023-0348 (760) 753-9940 November 7 , 1997 Nancy Shanahan 324--1, �ve Encinitas , California 92024 Subject: PRELIMINARY GEOTECHNICAL INVESTIGATION Proposed Single Family Residence Bonita Drive Encinitas , California 92024 A. P.N. 258-370-07 Dear Ms . Shanahan, In response to your request, we have performed a preliminary geotechnical investigation at the subject site for the proposed single family residence and garage . The findings of the investigation, laboratory test results and recommendations for grading and foundation design are presented in this report. From a geotechnical point of view, it is our opinion that the site is suitable for the proposed residence and garage, provided the recommendations in this report are implemented during the design _ and construction phases . If you have any questions , please contact us at (760) 753-9940 . This opportunity to be of service is appreciated. Respectfully submitted, A. R. BARRY AND ASSOCIATE _ Q��OFESSIp� R. A. R. Barry, P.,8. U, GE1i9 z Principal Engineer * Exp.3/31/98 �� Pv srq;�TEcVA FOF CALIF PRELIMINARY GEOTECHNICAL INVESTIGATION Proposed Single Family Residence Bonita Drive Encinitas , California A. P .N. 258-370-07 _ Prepared For: Nancy Shanahan 324 La Vita Ave . Encinitas , California 92024 November 7 , 1997 W.O. P-1537 Prepared By: BARRY AND ASSOCIATES P .O. Box 230348 Encinitas , CA 92023-0348 TABLE OF CONTENTS ._ INTRODUCTION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 SITE CONDITIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 PROPOSED DEVELOPMENT. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 SITE INVESTIGATION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 LABORATORY TESTING. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 GEOTECHNICAL CONDITIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 A. Soil . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 B. Expansive Soil . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 C. Liquefaction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 D. Groundwater . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 CONCLUSIONS AND RECOMMENDATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 A. GENERAL. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 B. GRADING. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 C FOUNDATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 D SLABS ON GRADE. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 E. DRAINAGE. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 F . FOOTING INSPECTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 G. PLAN REVIEW. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 LIMITATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 APPENDIX A. . . . . . . . . . . SITE PLAN APPENDIX B. . . . . . . . . . . .GRADING SPECIFICATIONS November 7 , 1997 w.o. #P-1537 _ Page 2 INTRODUCTION This report presents the results of our preliminary geotechnical investigation. The purpose of this study is to evaluate the nature and characteristics of the earth materials underlying the property and their influence on the proposed single family residences and garage . SITE CONDITIONS The property is located on the west side of Bonita Drive, between Melba Dr . and Requeza Street, in the City of Encinitas , California. See Site Plan, Appendix A. The lot slopes gently to the west at an average rate of approximately 3 . 5% with a total elevation difference of 2 . 5 feet, measured from the center of the lot from the east property line to the west property line . PROPOSED DEVELOPMENT Plans for the project have not yet been prepared, however it is our understanding that a one story single family residence and garage are being considered. SITE INVESTIGATION _ Three backhoe trenches were excavated on the three contiguous lots under investigation. Backhoe trench TP-2 was excavated on the subject lot near the south west corner of the proposed residence. Earth materials encountered were visually classified and logged by November 7 , 1997 w.0. #P-1537 Page 3 our field engineer . Bulk samples were obtained and transported to our laboratory for analysis . LABORATORY TESTING Classification The field classification of soils were verified through laboratory examination in accordance with the Unified Soil Classification System. The final classification is indicated below. -- GEOTECHNICAL CONDITIONS Soil Soils encountered in our backhoe excavation consists of brown silty sand topsoil , dry and loose to a depth of 6" , underlain with gray sandy clay to a depth of 18" , underlain with reddish brown silty sand. Hardpan encountered at 4" Very tight. SEE ENCLOSED SOIL LOG Expansive Soils Expansive soil was encountered in our backhoe trench from 6" to 18" and have an expansion potential in high range . However when properly mixed with on site silty sand the potential for expansion will be reduced to the low range . Final potential soil expansion will be determined at footing depth after grading. - Liquefaction The soils on the site are not considered subject to seismically induced soil liquefaction and soil instability due to such factors November 7 , 1997 w. o. #P-1537 Page 4 as soil type , density and lack of groundwater. Groundwater No evidence of groundwater was observed during the course of exploration and major groundwater related problems are not anticipated during construction. CONCLUSIONS AND RECOMMENDATIONS General The on site soils are suitable for the proposed grading and the support of the proposed single family residence and garage provided the recommendations in this report are implemented during the design and construction phase. Grading If slab on grade will be employed, grading will required in order to create a level pad for the slab on grade. See attached grading specifications, Appendix B Foundation General Footings for the proposed residence and garage should be a minimum of 12 inches wide and founded a minimum of 12" and 18" below grade for one and two story residence respectively. If stem wall and raised floor construction is employed footing depth may range from 18" to 36" and will be determined during footing excavation. November 7 , 1997 w. O. #P-1537 Page 5 Footings founded a minimum of 12" and 18" below grade may be designed for a bearing value of 1000 psf and 1500 psf for one and two story structures respectively. The bearing value indicated above is for the total of dead and applied live loads . This value may be increased by 33 percent for short durations of loading, including the effects of wind and seismic forces . Resistance to lateral load may be provided by friction acting at the base of foundations and passive earth pressure . A coefficient of friction of 0 . 3 should be used with dead-load forces . A passive earth pressure of 250 pounds per square foot, per foot of depth of fill penetrated to a maximum of 2000 pounds should be used in the - design. Minimum steel reinforcement should consist of 2-#5 bars one placed 3" from the bottom of the footing and one placed near the top of the footing. Slabs on grade Slabs on grade should be a minimum of 4 . 0 inches thick and reinforced in both directions with No. 3 bars , placed 18 inches on center. The slab should be underlain by a minimum 4-inch sand blanket which incorporates a minimum 6 . 0-mil Visqueen or equivalent moisture barrier in its center, for moisture sensitive floors . November 7 , 1997 W.O. #P-1537 Page 6 Utility trenches underlying the slab should be bedded in clean sand to at least one foot above the top of the conduit, then backfilled with the on-site granular materials , compacted to a minimum of 90 percent of the laboratory maximum dry density. However, sufficiently compacting the backfill deposits may damage or break shallow utility lines . Therefore , minor settlement of the backfill in the trenches is anticipated in these shallow areas . To reduce the possibility of cracks occurring, the slab should be provided with additional reinforcement to bridge the trenches . Drainage All roof water should be collected and transported to a suitable location via non-erodible device. Pad water should be directed away from foundations and around the residence to a suitable location. Pad water should not pond. Roof gutters are recommended. Footing Inspections Structural footing excavations should be inspected by this firm during the excavation and prior to setting formes . Plan Review A copy of the final building plans should be submitted to this office for review, prior to the initiation of construction. Additional recommendations may be necessary at that time. November 7 , 1997 w. 0. #P-1537 _._ Page 7 LIMITATIONS This report is presented with the provision that it is the responsibility of the owner or the owner' s representative to bring the information and recommendations given herein to the attention of the project' s architects and/or engineers so that they may be incorporated into the plans . If conditions encountered during construction appear to differ from those described in this report, our office should be notified so that we may consider whether or not modifications are needed. No responsibility for construction compliance with design concepts , specifications or recommendations given in this report is assumed unless on-site review is performed during the course of construction. -- The conclusions and recommendations of this report apply as of the current date. In time , however, changes can occur on a property whether caused by acts of man or nature on this or adjoining properties . Additionally, changes in professional standards may be brought about by legislation or the expansion of knowledge . Consequently, the conclusions and recommendations of this report may be rendered wholly or partially invalid by events beyond our _ control . This report is therefore subject to review and should not be relied upon after the passage of three years . November 7 , 1997 W.O. #P-1537 Page 8 If you have any questions , please do not hesitate to contact our office at 753-9940 . The opportunity to be of service is greatly appreciated. Respectfully submitted, A.R. BARRY_.4ND ASSOCIATES R oQROFESS/py� /vC/ Q� 41T ey �c'L A.R. B r Ell Principal Enginee GE119 Exp.3131198 cNN`G�� - ��OF CAl1F� APPENDIX ~ -HO dBlaW 01 .09V --�- ►il O (L N z � o J w z o- r W co 06 o -- CO M r o CL a_ N ~ Z CL Q � _o �f, , 7 N 'N, LO Z EL v� 06 co O i O M ti � C a L ~ N r Z IL Q , A F=P P' FE APPENDIX B RECOMMENDED GRADING SPECIFICATIONS GRADING INTENT The intent of these specifications is to establish procedures for clearing, compacting natural ground, preparing areas to be filled and placing and compacting fill soil to the lines and grades shown on the accepted plans . The recommendations contained in the preliminary geotechnical investigation report are a part of the recommended grading specifications and would supersede the provisions contained herein in case of conflict. INSPECTION AND TESTING A geotechnical engineer should be employed to observe and test the earthwork in accordance with these specifications . It will be necessary that the geotechnical engineer or his representative make adequate observations so that he may provide a memorandum that the work was or was not accomplished as specified. Deviations from these specifications will be permitted only upon written authorization from the geotechnical engineer. It should be the responsibility of the contractor to assist the geotechnical engineer and to keep him apprised of work schedules , changes and new information and data so that he may provide the memorandum to the owner and governmental agency as required. If in the opinion of the geotechnical engineer, substandard conditions such as questionable soil , poor moisture control , inadequate compaction, adverse weather, etc . are encountered, the contractor should stop construction until the conditions are remedied. Unless otherwise specified, fill material should be compacted by the contractor while near the optimum moisture content to a density that is no less than 90 percent of the maximum dry density determined in accordance with ASTM Test No. D1557-78 or other density test methods that will yield equivalent results . CLEARING AND PREPARATION OF AREAS TO RECEIVE FILL All trees , brush, grass and other objectionable material should be collected, piled and burned or otherwise disposed of by the contractor so as to leave the areas that have been cleared with a neat and finished appearance , free from unsightly debris . APPENDIX B Page 2 All vegetable matter and objectionable material should be removed by the contractor from the surface upon which the fill is to be placed, and any loose or porous soils should be removed or compacted to the depth determined by the geotechnical engineer. The surface should then be plowed or scarified to a minimum depth of 6 inches until the surface is free from uneven features that would tend to prevent uniform compaction by the equipment to be used. When the slope of the natural ground receiving fill exceeds 20 percent (5 horizontal to 1 vertical) , the original ground should be _ stepped or benched as shown on the attached plate . Benches should be cut to a firm, competent soil condition. The lower bench should be at least 10 feet wide and all other benches at least 6 feet wide , ground slopes flatter than 20 percent should be benched when considered necessary by the geotechnical engineer. FILL MATERIAL Materials for compacted soil should consist of any material imported or excavated from the cut areas that in the opinion of the geotechnical engineer is suitable for use in construction fills . The material should contain no rocks or hard lumps greater than 12 inches in size and should contain at least 40 percent of material smaller than 1/4 inch in size. (Materials greater than 6 inches in size should be placed by the contractor so that they are surrounded by compacted fines ; no nesting of rocks will be permitted. ) No material of a perishable , spongy or otherwise improper nature should be used in filling. Material placed within 36 inches of rough grade should be select material that contains no rocks or hard lumps greater than 6 inches in size and that swells less than 3 percent when compacted (as specified later herein for compacted fill) and soaked under an axial pressure of 150 psf . Potentially expansive soils may be used in fills below a depth of 36 inches and should be compacted at a moisture greater than the optimum moisture content for the material . PLACING, SPREADING AND COMPACTING OF FILL Approved material should be placed in areas prepared to receive fill in layers not to exceed 6 inches in compacted thickness . Each layer should have a uniform moisture content in the range that will allow the compaction effort to be efficiently applied to achieve the specified degree of compaction to a minimum specified density with adequately sized equipment, either specifically designed for soil compaction or of proven reliability. Compaction should be continuous over the entire area and the equipment should make APPENDIX B Page 3 sufficient trips to ensure that the desired density has been obtained throughout the fill . When moisture content of the fill material is below that specified by the geotechnical engineer, water should be added by the contractor until the moisture content is as specified. When the moisture content of the fill material is above that specified by the geotechnical engineer, the fill material should be aerated by the contractor by blading, mixing or other satisfactory methods until the moisture content is as specified. The surface of fill slopes should be compacted and there should be no excess loose soil on the slopes . UNIFIED SOIL CLASSIFICATION Identifying Criteria Group Symbol Soil Description COARSE-GRAINED (more than 50 percent larger than #200 sieve) Gravel (more than 50 percent GW Gravel , well-graded - larger than #4 sieve but gravel-sand mixture, smaller than three inches) little or no fines Non-plastic GP Gravel , poorly grad- ed gravel-sand mix- ture, little or no fines GM Gravel , silty, poor- ly graded, gravel- sand-silt mixtures GC Gravel, clayey, poorly graded, grav- el-sand-clay mixture Sands (more than 50 percent SW Sand, well-graded, smaller than #4 sieve) gravelly sands , little or no fines SP Sand, poorly graded, gravelly sands, little or no fines APPENDIX B Page 4 SM Sand, silty, poorly graded, sand-clay mixtures FINE-GRAINED (more than 50 percent but smaller than #200 sieve) Liquid limit less than 50 ML Silt, inorganic silt and fine sand, sandy silt or clayey-silt- sand mixtures with slight plasticity CL Clay, inorganic clay of low to medium plasticity, gravelly clays , sandy clays , silty clays , lean clays Liquid limit greater than 50 OL Silt , inorganic , silts and organic silt-clays of low plasticity MH Silt, inorganic , silts micaceous or diatomaceous fine , sandy or silty soils elastic silts CH Clay, inorganic , clays of medium to high plasticity, fat clays OH Clay, organic , clays of medium to high plasticity HIGHLY ORGANIC SOILS PT Peat, other highly organic swamp soils APPENDIX B Page 5 INSPECTION a Observation and compaction tests will be made by the geotechnical engineer during the filling and compacting operations so that he can state whether the fill was constructed in accordance with the specifications . The geotechnical engineer will make field density tests in accordance with ASTM Test No. D1557-78 . Density tests will be made in the compacted materials below the surface where the surface is disturbed. When these tests indicated that the density of any layer of fill or portion thereof is below the specified density, that particular layer or portion should be reworked until the specified density has been obtained. The location and frequency of the tests well be at the soil engineer ' s discretion. In general, the density tests will be made at an interval not exceeding 2 feet in vertical rise and/or 500 cubic yards of embankment. PROTECTION OF WORK During construction, the contractor should properly grade all excavated surfaces to provide positive drainage and prevent ponding of water. He should control surface water to avoid damage to adjoining properties or to finished work on the site . The contractor should take remedial measures to prevent erosion of freshly graded areas and until such time as permanent drainage and erosion control features have been installed. #" BARRY AND ASSOCIATES GEOTECHNICAL ENGINEERING P.O. Box 230348 Encinitas, CA 92023-0348 (760) 753-9940 November 6 , 1998 Nancy Shanahan ,,, � fiu':Xe•A'e 32-4-td-Vta Ave ._ Encinitas , California 92024 w Subject: ROUGH GRADING REPORT Proposed Single Family Residence Bonita Drive Encinitas , California 92024 A. P.N. 258-370-07 Reference: PRELIMINARY GEOTECHNICAL INVESTIGATION Proposed Single Family Residence Bonita Drive Encinitas , California 92024 A. P .N. 258-370-07 Dear Ms . Shanahan, - In response to your request, we have observed the grading operation and performed field density tests for the proposed residence on the above referenced property. The results of our density testing and _ laboratory testing are presented in this report. - - - Based on the results of our testing, it is our opinion that the fill was placed in an adequate manner and compacted to a minimum of 90 percent of the laboratory maximum dry density. - - - - If you have any questions , please contact us at 760 . 753 . 9940 . This opportunity to be of service is appreciated. Respectfully submitted, A. R. RR ND ASSOCIA �QROFESg A. R. B r , Principal Engi e sootlg � ZZ Exp. 3131102 m �A TfCHoC CALIF ROUGH GRADING REPORT Proposed Single Family Residence Bonita Drive Encinitas , California 92024 A. P.N. 258-370-07 Prepared for Nancy Shanahan 324 La VC-ta Ave . Encinitas , California 92024 November 6 , 1998 W.O. G- 1537 Prepared by: BARRY AND ASSOCIATES P . O. Box 230348 Encinitas , California 92023-0348 November 6 , 1998 w.o. # G-1537 Page 1 INTRODUCTION This report presents the results of our observations and field density testing of the grading project for the proposed residence . The project consisted of removing approximately 2 feet of loose surficial soil and re-compacting. The results of our density testing are presented on Table 1 . -- LABORATORY TEST DATA The laboratory standard for determining the maximum dry density was performed in accordance with ASTM D 1557-92 . Field density tests were performed in accordance with ASTM D 1556 . The results of the laboratory maximum dry density, for the soil used as compacted fill on the site, is summarized below: Maximum Dry Density Optimum Description (p.c . f . ) Moisture M - Brown silty sand 119 . 0 11 . 0 EXPANSIVE SOILS Pad grade soils have an expansion potential in the low range. DISCUSSION The following is a discussion of the grading operations , as they were performed on the site: 1 . Approximately 2 feet of loose soil was removed from one half the November 6 , 1998 W. O. # G-1537 Page 2 lot and stockpiled on the other half . The bottom of the excavation was probed with a steel probe and determined to be adequate . 2 . Fill soil was placed in lifts of approximately 6 . 0 to 8 . 0 inches thick. 3 . The soil was moistened as required to achieve optimum moisture content, and compacted with track mounted earth moving equipment. 4 . The fill was placed to a minimum of 90 percent of the maximum dry density, as indicated by our test results . 5 . Removal and recompaction included the area 5 ' outside the building line . INSPECTIONS All structural footings excavations should be inspected by an engineer prior to setting reinforcing steel . LIMITATIONS This firm assumes no responsibility for any alterations made without our knowledge and written approval to the slope or pad grade on the lot, subsequent to the issuance of this report. November 6 , 1998 W. O. # G-1537 Page 3 If you have any questions , please contact us at (760) 753-9940 . This opportunity to be of service is greatly appreciated. Respectfully submitted, A. R. BARRY D ASSOCI ,y o9 f ESB/p�y R. "Y� A. a r Principal Engi er w G00119 oC Exp. 3/31/02 Zo _ �2t ��rFCH��Gr�t 'FOFCAU ` W.O. # G-1537 Bonita Drive Encinitas , CA APPENDIX "A" LABORATORY TEST RESULTS TABLE I Field Dry Density and Moisture Content Moisture Dry Relative Test Test Content Density % No. Location Elev. cf Compaction 1 House pad grade -2 ' 13 . 2 109 . 5 92 2 House Pad grade-1 14 . 0 110. 7 93 3 House Pad grade 13 . 0 109 . 5 92