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HomeMy WebLinkAbout1986-08-26; City Council; 8438-2; Slope Stabilization Change Order - StagecoachCIT ? OF CARLSBAD - AGEND P BILL .c- / \ AB# ~3g-2 I TITLE: SLOPE STABILIZATION CHANGE ORDER - IDEPT. HD MTG.8/26/86 DEPT. P & R STAGECOACH PARK CITY All" CITY MGF i *rl u (d e 0 w 4 C rl (d g -rl -rl u a a (d !A w 0 4 B P u !A 0 w a Q) !z *d U C 0 0 Lo g $4 aJ u u 2 s aJ E-l Q 03 Q I N I 03 2 P G a d 0 z 3 0 0 ~ ~ RECOMMENDED ACTION: Approve slope stabilization work to be done by Chamac Inc. and appropriate funds from the Capital Improvement Project budget to cover the cost of the additional required work. RESQLH~~O~ AJO* . ~~~~~~ ITEM EXPLANATION: On March 11, 1986, a meeting was called by the Anden Group with City staff. The Anden Group is developing Santa Fe Knolls, a housing project across Mision Estancia from Stagecoach Park. Also present was RSI, Rick Engineering, Geocon (soils engineers for Stagecoach Park), Eberhart & Stone (soils engineers for Anden) and representatives from the Olivenhain Municipal Water District. The soils engineer for the developer explained that grading operations at Santa Fe Knolls uncovered a "landslide" that was not found during initial geological studies. The Anden Group data indicated that the slide started in the housing development and extended under Mision Estancia and into the park. To correct the problem, they felt a large buttress constructed on the park slope adjacent to Mision Estancia was needed. Staff directed Geocon, who did the original geotechnical work on the park, to investigate the alleged "slide". Originally Geocon did not do test borings in the north east corner of the park pads. Geocon took several borings in the area of the alleged slide. Their report findings indicated no presence of a slide. At this point, staff commissioned the soil engineering firm of Woodward Clyde to study the area and give an independent opinion. This was done because Eberhart & Stone still felt strongly that a landslide was present even after Geocon's report. Secondly, Olivenhain Municipal Water District agreed with Eberhart & Stone' opinion and subsequently shut off water in the area (feeling Mision Estancia and the waterline under the road were in danger.) Woodward Clyde drilled additional test borings. Their report confirmed Geocon's finding that no landslide existed. They did, however, identify an area in which the soils lying under Mision Estancia and.-in the slope of the park were of a Del Mar formation with fractures, sheers and remolded clay. because they concentrated on the various fill areas and building - With the presence of this type of soil condition, coupled with future landscaped watering to the south there is a strong possi- bility of a slope stability problem on the park side that could cause damage to the street and a 16 inch water line. Woodward Clyde's recommendation was to have a slope analysis done Staff then directed Geocon to perform the analysis. Geocon's final report stated the following: Agenda Bill No. Page 2 w= 0 I' . . . Although, in our opinion, the potential for shallow potential for sloughing failure or small block failure of the cut slope. A failure could extend into the northern portions of Mision Estancia, but the potential for extend- ing to the east bound lanes is considered very low. To reduce the potential for shallow slope instability, it is recommended that a "Stability Fill" be constructed . . (See Exhibit 2) slope instability is considered to be low, there is a Alternatives 1. Do nothing; repair if necessary in the future. 2. Reconstruct slope per soils engineer recommendations. Discussion Staff and park development committee have reviewed all the data and various alternative solutions pertaining to the slide/slope stability issue. It has been determined that becaus.e the developer to the south east has constructed a large deep buttress adjacent to Mision Estancia, any possible slide problem has been resolved. However, because our soils engineers have identified a soil condition that could be aggravated by future landscape watering and/or high water tables, staff feels that 700 feet of slope adjacent to the park should be stabilized, as recommended by the City's soil engineering consultant. The reason staff feels this work should be done is: 1. Slope stabilization would eliminate ongoing slope sloughing and repair. 2. Slope stabilization would eliminate possible damage to Mision Estancia and the 16 inch water line under the road. 3. The Olivenhain Municipal Water District has endorsed the staff's stabilization plan and has agreed to re-activate their wate line if the work is done. 4. Re-activating the water service would alleviate possible litigation by Olivenhain Municipal Water District and/or upstream developments. 'Agenda Bill No. & Page 3 0 Additionally, staff believes it would be beneficial for the park development contractor, Chamac, Inc., to perform this work through a change order to the original contract rather than go out for public b'id. The benefits are as follows: 1) Public bidding would require a lengthy and costly advertising and bidding process. 2) Having another contractor on site could present problems in coordination between contractors and create additional cost and time extension claims against the City. 3) Chamac has dealt fairly and in good faith with the City on minor change orders and the grading sub- contractor appears to be highly qualified. It is estimated that construction on the slope will delay the completion of the park by 30 to 60 days. Fiscal Impact COST OF PROJECT $341,000 (see detailed estimate attached, Exhibit 3) Staff recommends funds be allocated from unappropriated balance of the Public Facilities Fee fund (P.F.F.). Revenues in the Public Facilities Fund for 1985-86 were approximately $1.6 million above budget estimates. This additional revenue provides Council with an unappropriated balance of at least $1.6 million for the beginning of 1986-87. Exhibits 1. Resolution No. 8776 2. Exhibit 1, Plan showing area of unstable slope. 3. Exhibit 2, Section of slope stablization detail. 4. Exhibit 3, Cost estimate. * 5 1 2 3 4 5 e a RESOLUTION NO. 8776 A RESOLUTION OF THE CITY COUNCIL OF THE CITY OF CARLSBAD, CALIFORNIA, APPROVING SLOPE STABILIZATION WORK TO BE DONE BY CHAMAC, INC. AND APPROVING THE APPROPRIATION OF FUNDS FROM THE CAPITAL IMPROVEMENT PROJECT BUDGET TO COVER THE COST OF THE ADDITIONAL REQUIRED WORK WHEREAS, a "stability fill" has been recommended t 6 for a portion of Stagecoach Park; and 7 constructed to reduce the potential for shallow slope instabi 8! WHEREAS, slope stabilization would eliminate'ongoin 9 slope sloughing and repair; and 10 WHEREAS, slope stabilization would eliminate possib 11 endorsed staff Is stabilization plan as protection for their w 14 WHEREAS, the Olivenhain Municipal Water District ha 13 and 12 damage to Mision Estancia and a 16 inch water line under the 15 line and has agreed to reactivate their water line if stabili 16 work is performed; and 17 WHEREAS, reactivating the water service would allev 18 I/ upstream developments requiring water service; and 19 1 possible litigation by Olivenhain Municipal Water District an i 20 WHEREAS, Chamac, Inc. is the Contractor responsible 21 stabilization work; and 23 has been recommended by staff to perform the required slope 22 the construction and development of Stagecoach Community Park 24 I WHEREAS, sufficient funds are available in the un- 25 cost of this project, 26 appropriated balance of the Public Facilties Fund to support 27 , /// 28 /// I 1 0 e NOW, THEREFORE, BE IT RESOLVED that the City Counci 2 Fund, account No. 320-941, to account no. 320-840-1824-3191, 5 $329,000 from the unappropriated balance of the Public Facili 4 to be performed by Chamac, Inc. and approve the appropriati 3 the City of Carlsbad does hereby approve the slope stabilizat: cover the cost of the additional required work at Stagecoach 6 7 PASSED, APPROVED AND ADOPTED at a regular meeting c 8 day of August 1986, by the following vote, to wit: 9 City Council of the City of Carlsbad, California, held'on the 10 . NOES : None 11 AYES: Council Members Casler, Lewis, Kulchin, Chick and Pel 12 +-fL a4 b 13 ABSENT : None 14 I/ 12 VlL- ~ " , 13 ABSY" - ""- 14 I/ 15 ll ATTEST: 16 1 &&C&A d. a& I? I ALETHA L. RAUTENKRANZ, City Clerk 18 // (SEAL) I, 19 I 20 21 22 i I 23 24 25 1' 26 27 28 I .. . t 1:wa Ip)uawollr.la Da rm 'UlWpnm &2 LLiE 0 amdd~~*"~-+~'j~id 0 Qu 0 323 q .F 3cr q-gf I / .. .. .. . -. ." . 1- .-- --- -. - . " - - - - - ."""_ .. ... "_ - - .. . , "- " . . . "- - ' o ."_ , . . . ". .. _." "_ - ".. ". " - - - . . -. _. .. .;I : 1, 4. - _". "._ . - ... """"-"- - . .I - . . - ." . ". -.- 'I .. ." - ,,! "_ t ! -4 ._._, "-. . " . ". , ""_""I.- - .. . """""'"""-"--" " .. 3.. _"" __ ".. I +)"k _"" . """. "__ "" ." - ".. ""._ '..""" -- - _- . " ISW - . . ... -a . .. ..-. .- 0 STAGECOACH COMMUNITY PARK SLOPE STABILIZATION COST ESTIMATE 1. SUBCONTRACTOR Grading Staking Block OH&P @ 10% first $2,000 - 5% remaining Subcontractor Total 2. GENERAL CONTRACTOR General Conditions: 60 Days @ $400 per day Block Wall Footing OH&P, 15% General Contractor Total = $205,000 - 2,200 - 650 $207,850 = 10,292 - - = $218 , 142 = $ 24,000 1,112 $ 25,112 - 3,766 = $ 28,878 - Subcontractor (Grading) Total = $218 , 142 General Contractor (General Conditions) Total = 28,878 1% Bond $247 , 020 - 2,470 - Total = $249 , 490 3. GENERAL CONTRACTOR: Additional Parking Lot Redesign due to slope elongation as per RSI Design Concrete Work (Stairs, Curb, Masonry Iron Drainage Work Brow Ditch (D75) , Mow Strip Supervision 15% Contingency TOTAL : Block Wall) = $ 1,632 - 658 - 95 = 10,640 - 4,000 - 2,000 - - - - $ 19,025 2,853 $ 21,878 Subcontractor, General Contractor = $249 , 490 General Contractor Redesigned Parking Lot = 21,878 Subtotal = $271,368 EXHIBIT -3 e e 4. Engineering Service/RSI Plan Revision = $ 9,000 5. Soils Engineering & Inspection - 10% = $ 28,036 6. City Engineering Services - 5% = $ 15,420 7. Printing 8. Contingency - 5% - - 500 $3241324 = 16,216 $340,540 GRAND TOTAL Rounded Up = $341,000 Qlivenftain Municipal Wate 7 District BOARD OF DiRECTORS Ann L. Peay. F'resi&mt i-lowar? G. Golem. VICE President kfariec L. Denk. Treasurer Horold L. Gono. Secretory Ti~elrrra M. Miiior. Director lcj(>h OI.I','L'.;.NHAIN F<(?,41) E\CihiTA5 C:?LIFOR?IIA 02024 PHOSE !I\~O\ 753-h300 September 2, 1986 GENERAL COUNSE L'ernon A. Pe!tzer ENGINEER 9ovie Englneerrng C, MANAGER Wiliram H Holiingsu Mark Steyaert, Project Manager City of Carlsbad Park and Recreation Dept. 1200 Elm Avenue Carlsbad, California 92008 RE: Stagecoach Park Landslide Dear Mr. Steyaert: The undersigned is in receipt of your letter of August 28, 1986 requesting certain information regarding a realignment of the District's 16'' water line in Mision Estancia Road. The District would entertain an alternate alignment through the Anden property within the projects public streets. Realignment within Stagecoach Park is not acceptable. The District has been advised by its geotechnical consultants that the landslide may encroach a considerable distance into the park on the southwest side of Mision Estancia. Relocating the pipeline adjacent to Mision Estancia Road along the southeast side is also an unacceptable alternative. The Anden Project has constructed a 20 to 25' embankment at the edge of the Mision Estancia right-of- way. It would be necessary to bench into the embankment to construct a pipeline at this location. Any alignment within the existing Mision Estancia right-of-way is considered to be in the landslide zone. Attached is a District estimate of the cost to relocate the pipeline within the Anden public streets. This estimate is supplied for planning purposes only and may not include all of the costs of relocation. It should be noted that there is no planned service from the existing Mision Estancia pipeline through the landslide zone, however, there are two existing fire hydrants within this area. Removal and realignment of the water line will eliminate these two fire hydrants from a 700' stretch of Mision Estancia. It is suggessted that the Parks Department may wish to consult with the City of Carlsbad Fire Department regarding the lack of fire protection within this section of Mision Estancia. The District is prepared to cooperate with the City of Carlsbad wherever possible. Olivenhain wishes to reiterate that the perferred solution is still for the City to construct a buttress as recommended by three geotechnical 6 ,e. 0 consultants. The buttress solution protects all of the utilities within Mision Estancia Road as well as the Misian Estancia right of way. DCM: j sb 9-2-86 encl . ra (]p/; /.‘,,/ / ., . . ..__” d (P~~y”‘ ’ Assistant Manager Olivenhain Water District . -"""" ------"" - - ------- - --- .""""_ @ f - - - - - -. t# /ff€W) rp $7 EX/5T)+ 2;; f ($?U&5) V U "" "" - .-""" "-" "" - Portion to be abandoned. Portion to be realigned. "" STORM DRd/N f.4 5€MEAf7 mrE: JCT. 22, I 739 ROC. # 30 - 35D52 .' SiORN DRA/N '€As=#€.7 r 0. 0 GEOCON INCORPORATED Geotechnical Engineers and Engineering Geologists File No. D-3480-MO3 September 3, 1986 City of Carlsbad Parks and Recreation Department 1200 Elm Avenue Carlsbad, California 92008 Attention: Mr. Mark Steyaert Subject: STAGECOACH PARK CARLSBAD, CALIFORNIA CONSULTATION Gentlemen: The purpose of this letter is to restate recommendations made in our report of 3une 20, 1986 relative to placing a stability fill along Mision Estancia and to correct statements made during a recent council meeting pertaining to the calculated existing factor-of-safety. In our report of May 27, 1986 a factor-of-safety against sliding of 1.39 was calculated for the cut slope based on data obtained from exploratory borings placed by Geocon, Incorporated and Woodward-Clyde Consultants. Sometime later, a buttress keyway was placed along the east side of Mision Estancia. Subsequent examination of the excavation by our engineering geologist provided new data which prompted a revision of the recommended stability fill width as presented in our letter of June 20, 1986. Utilizing this same data the factor-of-safety against sliding was recalculated to be approximately 1.2. Because of this relatively low factor-of-safety, it remains our opinion that the slope be stabilized as recommended in the June 20 report. ?lease contact the undersigned if you have any further questions. Very truly yours, k )\$ OCON, INCORPORATED i Michael W. Hart CEG 706 MwH:wm (4) addressee 0533 Dowzv Dm7 San Dtec?. CA 32:E 619 695-2899 0, CITY OF CARLSBAD e PUBLIC WORKS PROJECT CHANGE ORDER [More than $51QQQ] 320-820-1 CONTRACT NO. 3191 & 3197 PURCHASE ORDER NO. 15697 BUDGET NO CONTRACTOR'S NAME Chamac PROJECT NAME AND NO. Stagecoach Community Park DIRECTOR OF PARKS & RECREATION CHANGE ORDER NO. 4 The contractor is directed to make the following changes. Changes shl include labor, material, and equipment; payment stated on this change includes all charges direct or indirect arising out of this additions, work. -The requirements of the specifications, where pertinent and no. conflict with this order shall apply to these changes. CHANGE 2 Slope stabilization work (see attached). REASON FOR CHANGE: Unstable soil condition on slope. COST : Total extra to contractor $ Total credit to the City $ -0- total net extra to contractor $ Not to Exceed $262,877 APPROVED BY CITY COUNCIL ON: APPROVAL : CONTRACTOR: Not to Exceed $262,877 -/ _- '_ /' //' 2' BY @/& ,/-+;;-/PGeFF~< "2/ Project Mang(Eier I/ / Date - ,,...e v ""*C \" &d L AeDA P&'rk@- RecreatiAn Director Date :' This change order is not effective unless signed by the Director of P and Recreation. 1 I- .@ ? 0 RSl Architecture. Landscape Architecture, Recreation and Environmental Planning August 19, 19RG Chamac, Inc. '747 Enterprise Street Escondido, California 92025 SUBJECT: CHANGE ORDER #4, STAGECOACH PAEIK, CARLSBAD You are hereby requested to comply with the following changes from the plans and specifications: ITEM $1 Install stabilization fill at the southeast end of the park according to Rick Engimeeriny Drawing SE-3, revised 8/6/86 arid Gcocon report dated June 20, 1386. Hauling of all fill material shall be between the hours of 8:OO a.%. and 3:30 p.m. Contractor shall shorc! up the existivrJ el.ect.:ci.cal vault.s. Variable costs are indicated due to the s.1ork:ing conditions required by the unstab1.e geologic f ornation. All work performed in 50 foot secticms within 55 chys, add $ 198,966.00. A1.I. work performed in 100 foot sections within 50 ciays, add .B 189,315.00. AI.]. work performed in 1-50 foot sections within 45 dr?:Ts, add, $ 189,315.00 . Two 50' exploratory sections opened up within 40 days, and approva.1 given by GeGcOn to do a11 'the work at one time, add General Condition costs are $4OO,OO per day. All work shall be .reviewed, tested, and approved by Geocon. Constri.lction Alternate ''A" . 1nstal.l retaining ws.I.l-, acilditional curbs, inow strip, catch b2sirfs, brow ditch, crib wa:Ll ar.d stairs accordinq to RsI Dr3whg ''st-shility Fill Revisions" dated 7/29/85, revisd 8/7/86; mil RSI I)x'~~wing "lrrigation Plan - East Sta'iii.1.Ft.y Fi3.L Fevizio::" dated 21/8/86 as attached. Add 4; 38,358.00. Construction A:Lt.ernate rrBrr. Inst-IIL retainj ny wa:L1, additional curbs, mow strip, hrw ditch, crib ~32.1, gutter, arft stairs zccoxling to ?.SI Dr;wir~g l'~b.abiliby FiI-I. RevisiCns" drrtctl 7/29/86, revised 3/7/86 and 3/1.5/86, and RSS 13rawir.g "1rri.gatiorr Plan - East Sta5iIity Fi 11 Re?isi<>i1'' dat.ed. 8/8/86 a; at.t:a.chcd. P.d.1 $ 26,122.00 . "" $ 175,953.00 . ' 2500 East Nutwood Avenue, Suite 210 Fullenon. California 92631 (713) 879-6373 'I - Y Total maximum Q ;.est.. ............................. * $ 237,324.00:i Total minimum cost.. ............................. $ 202,075.00'' Cost shall be determined by actual grading conditions in field and items constructed. Specifications, where pertinent and not in conflict with the above, shall apply to these changes. The contract time is hereby extended 40-55 calendar days to complete the above described work. This document shall become an amendment to the contract and all provisions of the contract shall apply thereto. PREPARED BY: ATE& s 20, IPSG RECREATION S ACCEPTED B DATE 8-20-86 Chamac Inc. A California Corpdation CONTRACTOR APPROVED BY DATE AGENCY REPR :':Does not include General Conditions. Minimum . $18,584.00 Maximum $25,553.00 I" 1 ,. ,+ : c.