HomeMy WebLinkAbout2024-05-09 Grandview extension SSO report CITY OF CITY OF TWIN FALLS
TWIN FALLS Public Works Department
119 South Park Avenue West
11,4v Twin Falls,ID 83301
OA<� Q�OQ
SFR V�NG
May 9, 2024
IPDES Permit No. ID0021270
RE: Wastewater spill reported on April 30,2024, and May 5,2024,west of Rock Creek lift station
To whom it may concern:
The first spill occurred on April 30,2024, at 1:27 pm. The City of Twin Falls Wastewater Collections
staff was contacted by the property owner of the field west of the City of Twin Falls Rock Creek lift
station(approximately 763 Addison Ave W, see attached Map). In the horse pasture, an 8-inch sewer line
travels above ground as an elevated pipe on supports that crosses Rock Creek(Pictures 1-3). This is the
same location of a spill caused by a failure of a comminutor at the Rock Creek lift station on February 13,
2024. However,this time,no backups were created by the lift station. The elevated pipeline where the
spill occurred was promptly jetted, and the blockage was cleared at 2:25 pm on April 30,2024. The
elevated pipe is extremely deteriorated,and above the normal waterline in the pipe,there are holes rusted
through the pipe(Picture 2). It is important to note that the section of the elevated pipe going over Rock
Creek is in a pipe sleeve and does not show signs of leaking or deteriorated pipe, similar to what is found
in the section going through the pasture. Each time the pipe is jetted, it further opens the rusted-out holes.
It also appears that wipes and toilet paper are catching on the rusted parts of the pipe, leading to
blockages.
City staff had driven by the area on the afternoon of April 25,2024, and did not see any active spills.
However,the exact duration of the spill remains unknown. Staff estimated the spill at the time of
reporting was flowing between 5-9 gpm. This would mean that over a 24-hour period,the volume of
water spilled would have been between 7,200 gallons and 12,960 gallons. It is unknown how much
wastewater made it to the river.
On May 1,2024,Idaho Department of Environmental Quality(IDEQ) staff visited the spill site with city
staff to inspect the impacted area. It was found that a portion of the spill flowed along a berm to the north
and eventually was able to flow into Rock Creek(Picture 4). IDEQ took samples for testing(Picture 5).
The second spill occurred on May 5,2024,at 11:31 a.m. I received a text with Picture 6 from the
wastewater collection staff stating that the pipeline again had a blockage,resulting in a spill. The pipeline
was jetted and cleared at that time.
On May 6,2024,in a proactive move,wastewater collection staff removed and replaced 83 feet of 8-inch
pipe associated with the spills(Picture 7). The elevated section of pipe with holes was either replaced or
covered with patches to eliminate any holes that had previously allowed wastewater to escape. This
should prevent the reoccurrence of spills that have been happening.
Up until approximately a year ago, city staff believed this pipeline was privately owned by the Rock
Creek Mobile Manor&RV Park,where most of the wastewater originates. A similar spill occurred in the
spring of 2023,and the city contacted IDEQ. At that time,because the line was believed to be a private
line,the city was not required to report the spill. After the spill,the city investigated further as to whose
responsibility it was to maintain the pipe. It was found that there is a recorded easement dedicated to the
City of Twin Falls for the pipe.
Once the city was aware of the responsibility for the pipe,the city actively pursued options for improving
the system for delivering wastewater through the pipe. On June 26,2023,Twin Falls City Council
approved$45,210 to hire an engineer to look into available solutions to fix the elevated pipe (Attachment
1). Soon after approval from the City Council,the city entered into an agreement with Consor
Engineering to assess the alternatives available for the Grandview gravity sewer line(Attachment 2).As a
result of the alternatives analysis, Consor Engineering provided a draft of the technical memorandum on
February 7,2024(Attachment 3). Using that memorandum,the city has been working on what is believed
to be the best option under the current conditions: to seek a contractor to complete a cure-in-place pipe
(CIPP)project for the pipe. Completing the CIPP on the sewer line will ensure that no further spills can
occur for many years to come. Even before the recent wastewater spills,city staff had scheduled to
request funds from the City Council for the CIPP project. The presentation and request to the City
Council is scheduled for Monday,May 13, 2024(Attachment 4).
At this time,the city believes the line is in working order and that the circumstances that led to the recent
spills have been fixed. The city is also making arrangements to ensure more permanent repairs are made
to the line.However, since this was not a budgeted project,there is a required process both statutorily and
by the city that requires the engineering, funding,bidding, and other steps to be completed within the
legal requirements.Unfortunately,this does take time. The city recognizes the urgency of improving
wastewater flow through the Grandview gravity sewer line and is committed to finding solutions to
prevent future spills. If there is someone from IDEQ who would like to receive regular updates on this
project,please let us know.
If there are further questions,please feel free to contact me.
Respectfully submitted,
Nathan Erickson
Environmental Manager
City of Twin Falls
(208)735-7272
nerickson&tfid.org
Map
Discharge to �''�• OW
Rock Creek - -
Approximate --- °
wetted area Location of blockage y,
.� and spill from pipe
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Picture 1 Location of the spill on the elevated pipeline.
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Picture 2—Zoomed-in picture of the spill before jetting.
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Picture 3—Wetted area south of pipe from the spill.
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®108°E (T) OO 42°33'47"N,114°29'46"W ±9ft ♦ 3637ft
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Picture 4—Berm running north along Rock Creek and location it enters Rock Creek.
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0 30 . 90 120 150
0 68°E (T) O 42°33'49"N,114°29'47"W ±9ft ♦ 3613ft
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Picture 5—Staff from IDEQ taking samples from Rock Creek.
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Picture 6—The fluorescent green dot on the hillside is the estimated location of the tap.
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Picture 7—On May 6,2024, an 83-foot section of pipe was replaced to prevent spills.
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ATTACHMENT 1
CITY OF
WIN NpLIS Date: Monday, June 26, 2023
To: Honorable Mayor and City Council
4<e StRVINn C` . From:
ACTION ITEM
Request:
Request to use wastewater reserves to fund an engineering contract to investigate solutions to fix an
elevated crossing of a failing sewer line over Rock Creek near Addison Avenue in the amount of
$45,210.00.
Time Estimate:
5 Minutes
Background:
Maintaining sewer lines is a priority for the wastewater collection department and the department
budgets for this yearly maintenance. In the mid 1960's an elevated sewer crossing over Rock Creek just
south of Addison Avenue West was constructed. This line served the trailer park on Grandview Drive.
Staff believed this to be a private sewer crossing not maintained by the city. The wastewater collections
department received notification that the line is failing and needs to be repaired. While working to
determine who needs to fix the line, staff found a recorded easement dedicated to the city of twin falls
for maintenance on the line. Contrary to our previous understanding, it appears the maintenance rests
with the city.
The request for$45,210.00 will cover the cost of the contract to pay an engineer to help determine the
best options for fixing the problem. The scope will also look to see if there is a way to increase the
capacity of this line, which may be beneficial to future development in that area.
Approval Process:
A majority vote of the Council to approve the use of wastewater reserves to fund the engineering
contract to determine the best solution.
Budget Impact:
This is an un-budgeted item and staff will need to use wastewater reserves to fund the investigation.
Regulatory Impact:
N/A
History:
N/A
Analysis:
N/A
Conclusion:
Staff recommends City Council authorize the $45,210.00 from wastewater reserves to fund an
engineering contract to offer possible solutions to fix the sewer crossing.
Attachments:
1. Rock Creek Crossing
2. Fee Estimate 2023 Rates - Grandview Sewer Alt Analysis DRAFT 6.13.2023
consor ATTACHMENT 2
SERVICES AGREEMENT
Consor Project No. W2320851D.00
This Services Agreement made and entered into on June 29,2023,by and between Consor NorthAmerica, Inc hereinafter
referred to as"CONSULTANT",and City of Twin Falls, ID, hereinafter referred to as"CLIENT":
WHEREAS,CONSULTANT and CLIENT wish to enter into this Services Agreement, hereinafter referred to as the"Agreement",
forthe furnishing of professional services in the field of engineering as further provided in this Agreement ("Services") for
the GRANDVIEW SEWER ALT ANALYSIS;and
WHEREAS,CONSULTANT possess the qua Iifi cations to perform necessary professional services for CLIENT on the terms
here n;
THEREFORE, inconsideration of the mutual promises and covenants of the parties hereto,it is agreed as follows:
TERMS AND CONDITIONS
1. SERVICES AND INSTRUMENTS OF SERVICE. CONSULTANT shall perform and CLIENT shall pay for the Services to be
performed by CONSULTANT pursuant to the"Scope of Services", attached as Exhibit"A". All Services not described in
Exhibit"A" shall be "Additional Services", shall not be included in any pricing in the Scope of Services and shall be
performed based on the CONSULTANT's standard fee schedule. All designs, reports, drawings, specifications, plans,
sketches, specifications, documents, work product and other deliverables prepared by or furnished by CONSULTANT
(collectively "Instruments of Service"), whether in hard copy or electronic form, shall be deemed the property of the
CONSULTANT, authored by the CONSULTANT, and that CONSULTANT shall retain all common law,statutory and other
reserved rights, including copyrights and all attendant intellectual property rights, of all Instruments of Service.
Submission or distribution of Instruments of Service to meet official regulatory requirements or for similar purposes in
connection with the Project is not to be construed as publication in derogation of the reserved rights of the CONSULTANT.
On the express condition that all amounts due to CONSULTANT are fully paid to CONSULTANT and that CLIENT is not in
default of this Agreement, CONSULTANT grants to the CLIENT a contingent, revocable, nonexclusive license to use the
CONSULTANT's Instruments of Service solely and exclusively for purposes of constructing, using, maintaining,altering
and adding to the Project. Except forthe limited,contingent and revocable license in this Section 1, no other license or
right ofthe Instruments of Service shall be deemed granted or implied under this Agreement.The CLIENT shall not assign,
delegate,sublicense, pledge or otherwise transfer any license granted herein to another party without the priorwritten
agreement ofthe CONSULTANT in each instance. All Instruments of Service are fortheexclusive use of the CLIENT forthe
Project specified,whethercompleted ornot.No otheruse ofthe Instruments of Service is authorized under this Agreement
without CONSULTANT's prior written authorization in each instance. CLIENT releases CONSULTANT from liability and
agrees to defend, indemnify, protect and hold harmless CONSULTANT from any and all claims, liabilities,damages or
expenses arising, in whole or in part, from any use of the Instruments of Service not expressly authorized by this
Agreement and directly supervised by CONSULTANT. Further, to the extent permitted by law, CLIENT further agrees to
indemnify and hold harmless the CONSULTANT and its consultants from all costs and expenses, including the cost of
defense, related to claims and causes of action asserted by any third person or entity to the extent such costs and
expenses arise from the CLIENT's use of the Instruments of Service under this Section 1. Any unauthorized use of the
Instruments of Service shall be at the CLIENT's sole risk and without IiabilitytotheCONSULTANT.
2. PAYMENTTERMS. Invoices will be submitted at least monthly for services rendered. Terms of payment are net forty-five
(45)days from date of invoice.Paymentwill be made to CONSULTANT at the address specified on CONSULTANT's invoice.
If CLIENT reasonably objects to all or any portion of an invoice,CLIENT shall notify CONSULTANT in writi ngwithi n ten(10)
days from the date of receipt of CONSULTANT's invoice,give reasons for the objection,and pay that portion of the invoice
not reasonably in dispute. CONSULTANT may suspend all Services until payment is received. Any amounts due to the
CONSULTANT under this Agreement may bear interest atthe rate of 1.5%per month.
3. STANDARDOF CARE. CONSULTANTwill perform its Services using thecare and skill ordinarily exercised by professionals
performing similarservices under si mi lar conditions in the same or similar locality as CONS ULTANT("Standard of Care-).
CLIENT acknowledges that CONSULTANT's Services may be imperfect, inaccurate or not fully compliant with all relevant
laws or ordinances, but that such Services are compliant with the Standard of Care. CONSULTANT's sole obligation of
performance under this Agreement is to perform pursuant to the Standard of Care,to the exclusion of any other higher
standards,warranties or obligations. No otherwa rra nty,gua ra nty,or representation,either express or implied,is made or
intended in this Agreement. CONSULTANT shall not be responsible forCLIENT's directive orsubstitution,orforthe CLIENT's
acceptance of non-conforming Work, made or given without the CONSULTANT's written approval.To the extent any
Services are not required to be performed by a licensed or registered professional,such services shall not be subject to
the Standard of Care required hereunder. Subject to and as limited by the Standard of Care, CONSULTANT is responsible
for the technical accuracy of its final work product. Subject to the Standard of Care, CONSULTANT shall correct any
deficiencies in any final work product without additional compensation except to the extent such action is attributable
to actions by CLIENT or deficiencies in CLIENT furnished information or other actions,omissions or errors of CLIENT or
CLIENT's architects, other design professionals, contractors, agents or employees. CLIENT is responsible for and
CONSULTANT may rely upon the accuracy and completeness, to the same standard of care, of all CLIENT furnished
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consor SERVICES AGREEMENT
' Consor Project No. W2320851D.00
information,specifications,studies and documents (collectively "Client Information")without CONSULTANT's need to
confirm any Client Information. Both parties recognize that the Client Information may change and, in that event,the
CLIENT and CONSULTANT shall appropriately adjustthe Services, Scopeof Services,and theCONSULTANT's compensation.
4. INSURANCE. CONSULTANT shall procure and maintain insurance as follows: Worker's compensation and employer's
liability as required by applicable law; comprehensive general liability ($1,000,000 per occurrence / $2,000,000
aggregate);professional liability($1,000,000 peroccurrence/$2,000,000 aggregate);and automobile liab i lity($1,000,000
-combined single limit). If requested by CLIENT,CONSULTANTshall add CLIENT(and any lender of CLIENT)asan additional
insured to the comprehensive general liability policy.
S. CHANGE ORDERS OR MODIFICATIONSTO SERVICES. CLIENT shall be advised priorto the execution of services deemed
by CONSULTANT to be Additional Services. Any changes in the work,changes in the Project,changes in the Scope of
Services beyond those in Exhibit"A",changes in the type of Services required beyond those in Scope of Services,acts of
God or casualty(collectively a "Change"), such Change shall be Additional Services and shall result in a change to the
amountsstated for Services onthe Scope of Services. ForanyChanges,CONSULTANT shall prepare and present to CLIENT
a written authorization to modify this Agreement to account forthe change("Change Order"). If CLIENT and CONSULTANT
cannot agree on the fees for any Additional Services,CONSULTANT shall have the right to suspend all Services until an
agreement is reached. If unforeseen circumstances substantially alter the Services or the risks involved in providing
such Services, CONSULTANT shall promptly notify and consult with the CLIENT but will act based on our sole judgment
where risk to personnel is involved. If specific periods of time or dates for rendering Services are set forth in this
Agreement,and if such periods of time ordates are changed through no fault of CONSULTANT exclusively, the time and
compensation for Services shall be subject to equitable adjustment. It shall be the sole responsibility of the CLIENT to
inform the CONSULTANT of any schedules or time limitation in CONSULTANT's performance of its Services. Absent any
express written agreements as to the ti me required to perform the Services, CONSULTANT shall not be responsible fora ny
delay in performing Services by any particular date or period of time. If CLIENT requests a Change or other revision in the
scope, extent,orcharacter of the project,the CLIENT shall issue a Cha nge Order in which the Parties shall agree on an
equitable adjustment in CONSULTANT's compensation,schedule, orboth.
6. LIMITATION OF LIABILITY.To the maximum extent permitted by law,CLIENT agrees that the liability of CONSULTANT to
CLIENT for any and all injuries,damages, claims, losses, expenses, or claim expenses (including attorney's and expert
witness fees) arising out of or related to, but are not limited to, the negligent acts(s), error(s), or omission(s) of
CONSULTANT in performing services as stated within the Agreement, shall be limited to the lesser of: (a) one million
dollars ($1,000,000);or, (b)the tota I a mount of professional liability insurance available at the ti me any insurance claim
made undersuch policy ispaid. CLIENT acknowledges that this limitationof liability isamaterial term of this Agreement
for the CONSULTANT, and that but for this limitation of liability,the CONSULTANT would not have entered into this
Agreement. To the extent damages are covered by property insurance, the pa rti es wa ive a II rights against each other a nd
against the contractors,consultants,agents,and employees of the other for damages,except such rights as they may
have tothe proceeds of such insurance.
7. OTHER DAMAGES. To the fullest extent permitted by law,CLIENT and CONSULTANT waiveand forever release each other
and the other's employees, officers, directors, agents, insurers and partners any and all claims for or entitlement to
damages categorized as special, incidental,indirect,stigma,harm to reputation,lost profit,loss ofvalue, loss of use, lost
marketability, or consequential damages, arising out of or resulting from or in any way related to the Agreement.
Notwithstanding the foregoing, nothing in this Agreement shall release or waive CONSULTANT's recovery of its full fees
due under this Agreement,whether they be considered profit or not.
S. FORCE MAJEURE. CONSULTANT shall not be responsible fordamages ordelays in performance caused by force majeure,
actsof God,strikes,lockouts,accidents,shortageof materials,shortageof labor,vandalism, pandemic(including COVID-
19),orother events beyond CONSULTANT's control.
9. SITE ACCESS. If entry on a project site is required to perform the services agreed to under this Agreement,CLIENT, at its
cost,shall arrange for right-of-entryto the property. CLIENT represents that it possesses necessary permits and licenses
forthe activities required at the site under this Agreement.
10. HAZARDOUS CONDITIONS. If a hazardous environmental condition is encountered or alleged, CONSULTANT has the
obligationto notify CLIENT and,tothe extent required by applicable laws and regulations, notify appropriate authorities
CLIENT warrants that it has disclosed, to the best of its knowledge, to CONSULTANT, the existence of any hazardous
environmental conditionat ornear thework site.
11. CLIENT RESPONSIBILITIES. CLIENT shall provide information in a timely manner regarding requirements for and
limitations on the Project, including a written program,CLIENT objectives;schedule; constraints and criteria;and site
requirements. CLIENT shall identifya representative authorizedto acton the CLIENT'S behalf with respect tothe Project
CLIENT shall render decisions and approve the CONSULTANT'S services and work product in a timely manner in order to
avoid unreasonable delay in theorderly and sequential progress of the Services. CLIENT shall furnish surveys to describe
physical characteristics, legal limitationsand utility locationsfor the site of the Project, and a written legal description
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consor SERVICES AGREEMENT
' Consor Project No. W2320851D.00
of the site.
12. CONSTRUCTION AUTHORITY. If the work detailed under this Agreement goes to construction,CONSULTANT shall not: (a)
direct, inspect, supervise or have control over the Contractor's work; (b) have authority over or responsibility for the
means, methods, techniques, sequences, or procedures of construction selected by Contractor;(c) be responsible for
safety precautions and programs related to the Contractors work in progress; (d) be responsible for any failure of
Contractorto comply with the laws and regulations. CONSULTANT shall not be responsible forthe acts oromissions of
the Contractor(s) or any of the Contractors agents or employees or any other persons (except CONSULTANT's own
employees, agents and subcontractors) at the work site or otherwise furnishing or performing any of the Contractors
work;or forany decision made on interpretations or clarifications of the Contract Documents given by CLIENT without
direct consultation and advice of CONSULTANT. CONSULTANT shall be under no obligationto report any deviationsfrom
the Instruments of Service unless expressly requested to do so by the CLIENT,and only to the extent such work is easily
viewable and such deviationsare actually known to CONSULTANT.
13. SUB-CONSULTANTS. CONSULTANT may arrange for some of the Services to be performed by outside consultants to
CONSULTANT ("Sub-Consultants"). CONSULTANT shall supervise Sub-Consultant's work but Sub-Consultant shall be
responsible to perform to the Sub-Consultant's Standard of Care. All communication to any Sub-Consultant shall be
through the CONSULTANT. All payments from CONSULTANT to any Sub-Consultant shall be expressly contingent upon
CONSULTANT's receipt of full payment from CLIENT. CONSULTANT shall not be obligated to pay any Sub-Consultant unless
and until CONSULTANT receives full payment from CLIENT.
14. SUCCESSORS;THIRD PARTIES. This Agreement shall bind the successors and legal representatives of both parties.
Nothing inthisAgreement shall be construed to give any rights or benefits to anyone otherthanthe parties signed below.
15. DISPUTE RESOLUTION. CLIENT and CONSULTANT agree to negotiate all disputes through good faith negotiations. If the
partiesfail to resolve a dispute after sixty(60) daysof good faith negotiations,CLIENTand CONSULTANT agree to submit
any and all unsettled claims, counterclaims, disputes, and other matters in question arising out of or related to this
Agreement or breach thereof to resolution through mediation to be administered privately or through JAMS
(www jamsadr.com)according to its Construction Industry Mediation Rules. CLIENT and CONSULTANT shall exercise their
rights to litigation only after submitting to mediation.Venue for litigation shall be the federal or state courts where the
Project is located.Except as otherwise provided herein and to the extent allowed bylaw,each partyshall be responsible
for its own lega I costs and attorneys'fees.
16. TERMINATION. Either party may terminate this Agreement without cause upon ten(10) day advance written notice. In
the event CLIENT requests termination priorto completion of the proposed services, CLIENT agrees to pay CONSULTANT
for all costs incurred to date of notice of termination. The limitation of liability and indemnity obligations of this
Agreement shall be binding notwithstanding any termination of thisAgreement.
17. CONTROLLING LAW. This Agreement shall be governed and construed in accordance with the laws ofthe Statewhere the
Project is located.
18. OMIT
19. ENTIRE AGREEMENT. This Agreement including Exhibit "A", the following listed documents and all attachments
incorporated herein by reference, represents the entire Agreement and understanding between the parties and any
negotiations, proposals or oral agreements are integrated herein and are superseded by this written Agreement. Any
supplement or amendment to this Agreement shall be in writing and signed by the parties.
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consor SERVICES AGREEMENT
Consor Project No. W2320851D.00
ACCEPTED-THE SERVICES SPECIFIED HEREIN, ASSOCIATED BILLING TERMS/PRICING,TERMS AND CONDITIONS,
AND EXHIBITS ARE HEREBY ACCEPTED BY THE UNDERSIGNED.
CONSOR NORTH AMERICA,INC
DocuSigned by: DocuSigned by:
SusH 2. 0."d
AUTHORIZED SIGNATURE(CLIENT) AUTHORIZED SIGNATURE(CONSULTANT)
Joshua R.Baird Public Works Director Craig B. Anderson, pll i nci pal Engineer III
CLIENTNAME &TITLE NAME &TITLE
7/3/2023 1 4:07:34 PM EDT
DATE OF ACCEPTANCE
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n consor
ATTACHMENT A
www.consoreng.com
EXHIBIT A
SCOPE OF WORK
GRANDVIEW GRAVITY SEWER ALTERNATIVES
ANALYSIS
CITY OF TWIN FALLS, ID
Introduction/General/Background
This Scope of Services has been separated into three tasks for clarity and is described in detail below.
Project Understanding and Assumptions
The City of Twin Falls, ID(City) recently assumed ownership, operation and maintenance of a gravity sewer
serving the Rock Creek Mobile Manor on Grandview Drive.The gravity sewer has condition issues and needs
repair and rehabilitation or replacement. The City recently completed spot repairs to the aerial gravity
sewer crossing of Rock Creek. The City is interested in considering more extensive repairs to the gravity
sewer crossing steel pipe. The City is also interested in considering options to provide additional sewer
service area to the southwest along Grandview Drive and a parcel immediately west of Twin Falls County
West facilities on Addison.
This scope of work is for an alternatives analysis of gravity sewer repair and replacement options. Design
services and services during bidding and construction will be provided as an amendment to this scope of
services.
Scope of Services
Consultant will perform the following services.
Task 1 - Project Management
Objective
Provide overall leadership and team strategic guidance aligned with City staff objectives. Coordinate,
monitor, and control the project resources to meet the technical, communication, and contractual
obligations required for developing and implementing the project scope.
Activities
1.1 Invoices/Status Reports
Consultant will prepare monthly invoices, including expenditures by task, hours worked by project
personnel, and other direct expenses with the associated backup documentation. Monthly status reports
will accompany each invoice and include comparisons of monthly expenditures and cumulative charges to
budget by Task, including cost-to-complete, earned value, cash flow, and firm participation.
Consor•June 2023 • Grandview Gravity Sewer Alternatives Analysis •City of Twin Falls, ID
Scope of Work• 1
1.2 Coordination with the Owner
Consultant will maintain communication with the City through meetings via voice, online hosted meetings,
and e-mail communication.
1.3 Management and Coordination of Staff
Consultant will manage and coordinate the technical and scope issues of the overall project. Progress
meetings will be conducted as appropriate.
In addition, a Health and Safety Plan (HASP) will be created that is custom to this project. It is the
Consultant's policy to promote and foster a safe work environment for the team both inside the office and
in the field. The HASP will align with all local Occupation Health and Safety Administration (OSHA)
requirements, client safety plans and program, and contractor safety plans.
Task Deliverables
➢ Consultant shall deliver to the City a monthly invoice and status report covering:
o Work on the project performed during the previous month.
o Meetings attended.
o Problems encountered and actions taken for their resolution.
o Potential impacts to submittal dates, budget shortfalls or optional services.
o Budget Analysis.
o Issues requiring project team action.
Assumptions
➢ Consultant assumes a Notice to Proceed date by June 28, 2023.
➢ Consultant assumes up to four(4)half-hour status meetings with the Consultant's Project Manager
and the City Project Manager.
➢ Project duration will be 4 months; therefore, it is assumed that there will be up to 4 progress
payments/status reports.
Task 2 — Kick-Off Meeting and Data Collection
Objective
Consultant will perform hold a kickoff meeting and site visit with the City.
Consor•June 2023 • Grandview Gravity Sewer Alternatives Analysis •City of Twin Falls, ID
Scope of Work• 2
G:\PDX_BD\Clients\Twin Falls, ID\2023 RFQ Professional Services Roster2-23\Contracting\Grandview Sewer
Analysis\Scope of Work Grandview Alt Ana lysis_6.5.2023.docx
Activities
2.1 Kick-Off Meeting
Consultant will attend a kick-off workshop with the City to introduce project staff; review communication
protocol, scope, schedule and budget; and review initial alternatives. Consultant staff will also perform a
site visit of the proposed alignment alternatives after the kick-off workshop.
2.2 Coordination with the Owner
Consultant will review data provided by the City that is assumed to include:
• Record drawings of the existing gravity mains in the area
• Record drawings of the existing bridge that support the aerial crossing
• Existing CCTV inspection tapes and reports of the existing gravity mains and manholes in the area
• Recorded utility easements in the project area
• Updated GIs shapefiles (utility linework, aerial photography, parcels, etc.)
• Hydraulic model output information from City's sewer system hydraulic model.
Task Deliverables
1. Notes from the kick-off meeting(PDF),
Assumptions
1. Survey, potholing and geotechnical analysis are not included in this scope.
2. City will coordinate site access as required for site visit.
Task 3 — Alternatives Analysis
Objective
Consultant will perform an alternatives analysis based on the discussion during pre-scoping discussions.
Activities
3.1 Alternatives Analysis
Consultant will review up to three alignment alternatives. The three alternatives are:
• Repair and rehabilitation of existing gravity sewer: Cured-In-Place Pipe (CIPP) and pipe bursting
options.
• Expanded sewer service to the southeast.
• Expanded sewer service to the north for the old gravel quarry parcel.
Analysis of these alternatives will include:
Consor•June 2023 • Grandview Gravity Sewer Alternatives Analysis •City of Twin Falls, ID
Scope of Work• 3
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• Review current and projected hydraulic loading compared to the existing capacity of the gravity
main in the project area. Consultant will use the hydraulic model flow output from current
Collection System Master Plan and manning's equation capacity calculations.
• Hydraulic analysis will be used to understand requirements for bypass pumping during
construction and final hydraulic capacity of the selected alternative.
• Summary of requirements to abandon the existing gravity main.
• Comparison of alternative concepts including:
o Conceptual level layout of pipeline and manholes
o Figure illustrating the alternatives
o Bypass requirements
o Trenchless construction recommendations/requirements
o Conceptual level cost estimates for alternative comparison.
The Consultant will develop a draft technical memorandum to summarize the alternatives analysis, present
schematic level concepts with figures, and present the draft findings of the alternatives at a review
workshop with the City. Consultant will finalize the technical memorandum, including a recommended
alternative, based on the discussions at the review workshop. Consultant will also develop a scope of work
for final design of the replacement alternative.
Task Deliverables
1. Draft Alternatives Analysis Technical Memorandum in PDF format.
2. Summary of workshop notes in pdf format.
3. Final Alternatives Analysis Technical Memorandum in PDF format.
4. Scope of Work for Final Design in pdf format.
Assumptions
1. City will lead discussions with private landowners and any easement or access negotiations.
2. Public meetings are not required.
3. Environmental permitting and coordination with regulators is not included in this scope.
4. The existing hydraulic model and flow projections/population growth projections, wet weather
peaking factors from Collection System Master Plan will be provided by the City's modelling
consultant for this this analysis. Manning's formula capacity will be used to determine sewer
capacity for existing and proposed alternatives.
5. The technical memorandum will not be submitted to the Idaho Department of Environmental
Quality.
6. Final design, any field investigation required to support final design (e.g. survey, geotechnical
investigation),and Services During Bidding and Construction will be provided under an amendment
to this agreement.
Budget
Payment will be made at the Billing rates for personnel working directly on the project, which will be made
at the Consultant's Hourly Rates, plus Direct Expenses incurred.
The overall budget estimate breakdown for this work is outlined in the table below.Consultant will manage
the work identified to the aggregate authorized budget amount which shall not be exceeded without prior
written authorization from the City.
Consor•June 2023• Grandview Gravity Sewer Alternatives Analysis •City of Twin Falls, ID
Scope of Work•4
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Task Amount
Task 1—Project Management $4,180
Task 2—Kick-Off Meeting and Data Collection $7,882
Task 3—Alternative Analysis $33,148
Total $45,210
Project Schedule
Assuming a Notice to Proceed by June 28, 2023,the work provided under this scope of work is anticipated
to be completed per the milestone dates provided in the table below. Consultant will make every effort to
complete the work in a timely manner; however, it is agreed that consultant cannot be responsible for
delays occasioned by factors beyond its control, nor by factors that could not reasonably have been
foreseen at the time this scope was executed.
Task Completion Date
Task 1 - Project Management October 31, 2023
Task 2—Kick-Off Meeting and Data Collection July 12, 2023
Task 3—Alternative Analysis October 31, 2023
Consor•June 2023• Grandview Gravity Sewer Alternatives Analysis •City of Twin Falls, ID
Scope of Work• 5
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ATTACHMENT 3
"n consor
DRAFT Technical Memorandum
Date: February 7, 2024
Project: Grandview Gravity Sewer Alternative Analysis
To: City of Twin Falls, Idaho
From: Mark Cummings, P.E.
Eric Weimer, P.E.
David Montgomery
Consor
Introductiari
The City of Twin Falls (City) assumed ownership of a gravity sewer that serves the Rock Creek
Mobile Manor on Grandview Drive. The gravity sewer line includes an aerial crossing over Rock
Creek and above ground steel piping that directs flows to the Rock Creek Lift station. This aging
stretch of gravity sewer requires repair and rehabilitation work or a complete replacement. The
existing sewer is an 8" concrete pipe from Manhole 134-66 to 134-65. From manholes 134-65 to 134-
62, the sewer is an exposed 8" steel pipe, including the cased crossing over Rock Creek. The
existing sewer transitions back to an 8" concrete pipe from 134-62 over to the lift station. Numerous
holes have been patched and repaired on portions of the steel pipe. The pipeline is likely in
corroded and in poor condition due to hydrogen sulfide gas release from the wastewater flowing
in the pipe. The existing sewer system is shown in Figure 1. Existing conditions of the pipe are
located in Appendix A. The As-built Drawings are located in Appendix B.
The City requested Consor evaluate the repair and replacement options for this sewer line
(between manholes 134-66 to 134-6). Additionally, the City requested analysis of extending the
sewer line south down Grandview Drive to provide a larger potential sewer service area. Lastly,
the City would like to look into adding a sewer service to the lot north of HWY 30, east of Rock
Creek RV Park and immediately west of the Twin Falls County West facilities.
This Alternatives Analysis Technical Memorandum (TM) outlines alternatives to improve/expand
the gravity sewer lines identified by the City.
Hydraulics
The calculated average and peak flow rates of the Grandview gravity sewer are based on 62 homes
in the Rock Creek Mobile Manor with three (3) persons per home generating 100 gallons per
person per day. For a sewer service area of this size, per Ten State Standards, the average to peak
flow is a ratio of 1:4.16. These assumed numbers provide an average and peak sewer flow of 12.9
W2320851D.00 Page 1 of 15 Grandview Gravity Sewer
February 2024 City of Twin Falls, ID
gpm and 53.7 gpm, respectively. Existing sewer flows were measured at the Grandview Extension
Sewer Main over a period of two weeks starting in September of 2023. Flow rates were measured
every 15 minutes.The average flow measured during this period was 29.5 gpm. The minimum flow
was 6.9 gpm, and the maximum flow was measured at 91.5 gpm. These measured rates provide
the basis for the provided repair and replacement alternatives.
An 8" steel pipe at the minimum Ten State Standard slope of 0.4% could safely handle
approximately 340-480 gpm depending on age and friction characteristics. Typical friction factors
for welded steel pipe range from .01 to .014.
W. lur - s
30 ADDISON AVE W
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Figure 1: Project Map — Existing Gravity Sewer
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Alternatives Analysis
Consor identified and analyzed three improvement alternatives. The alternatives range from
repair of the damaged line, to analysis of replacing and extending the sewer lines from Rock Creek
Lift Station past Rock Creek Mobile Manor and south to E 3600 N. The goal of the alternatives
analysis is to provide the City of Twin Falls with the costs and consideration of
advantages/disadvantages for the various options so the City can decide its preferred alternative.
Alternative 1 — Repair Damaged Sewer Line
This alternative is to repair the damaged sewer line from manhole B4-66 to 134-6. The interior of
the existing pipe would be required to be cleaned, followed by repair using a Cured-In-Place Pipe
(CIPP) re-lining. CIPP is a method of trenchless pipe restoration utilizing a flexible liner that is
inserted into the existing pipe. This lining is then cured and hardens to create a new pipe within
the existing pipe. Figure 2 highlights the Alternative 1 repair of the damaged gravity sewer line.
The advantage of this alternative is an overall lower construction cost by excluding trench
excavation, asphalt or gravel surface repairs, landscaping removal and replacement, and major
erosion and sediment control measures. The existing creek crossing and pipe supports can most
likely be reused for this alternative. CIPP lining would protect the pipe from further internal
corrosion and can be thickness controlled to provide structural support. The project duration is
also the shortest out of all alternatives, which reduces both the time and cost of sewer bypass
pumping operations. Traffic control measures would be also be minimized, and existing sewer
easements would remain in place. Regulatory requirements for this alternative are lessened due
to the reduced impact of the existing Rock Creek and surrounding floodplain boundaries.
The disadvantage of this alternative is that lining the sewer line does not replace the weathered
exterior pipe, or allow for upsizing of the pipe size for future flows of an expanded service area.
The exterior of the line is mostly exposed from B4-64 to 134-62 which has led to the external
degradation of the steel pipe over time. Internal degradation likely occurred due to the corrosive
hydrogen sulfide conversion to sulfuric acid on the crown of the pipe. The pipe has already had
numerous patches and repairs performed, and the exterior of the degraded pipe would remain
exposed to the elements. Some additional external patches or repairs may be necessary to
complete before a CIPP lining repair could begin. Even though sewer bypass operation timelines
are short, the logistics of bypass operations are complex because there is no other alternate
gravity sewer to discharge into. This alternative could either require the use of a long bypass
pipeline (approximately 2,000 LF) or using vactor trucks to haul sewage.
Costs for the alternatives are discussed later in this TM.
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Figure 2:: roject Map — Repaired Gravity Sewer
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Alternative 2 — Replace Damaged Sewer
This alternative includes the replacement of the damaged sewer main in a similar alignment with
a replacement 8-inch pipeline. The new sewer would cross Rock Creek similar to the existing in an
aerial cased crossing but in a new alignment just south or north of the existing pipeline. Figure 3
highlights the replaced sewer and shows the potential to extend sewer to the south along
Grandview Drive which will be discussed further in this memorandum. During construction, the
sewer flow will be temporarily bypassed during connections to the existing sewer.
Disadvantages of this alternative are the vastly increased scope and cost, difficulty in installation,
and a longer project duration. Trench excavation, sewer pipe installation, manhole replacement,
and surface repair are all items that have to be factored into the construction scope and budget
compared to a CIPP repair alternative.
This alternative could also allow for the replacement of the existing sewer with a larger diameter
pipe to meet possible future flow demands. However, replacement of the aerial crossing between
134-64 and 134-62 with a larger diameter pipe would also require a new larger diameter casing for
the aerial Rock Creek crossing. Secondly, increasing the diameter of the replacement pipe would
require possible refurbishment of the existing weathered pipe supports or the installation of new
pipe supports, depending on the selected sewer alignment. Both the refurbishment or installation
of new above-ground pipe supports, and the installation of a new aerial creek casing would likely
require the need for a structural engineer to desig e new supports and verify the spacing
required for the new sewer pipe. %k
Another disadvantage of this alternative is the possible permitting required for the replacement
of the aerial pipeline across Rock Creek and above ground pipe within the existing field. Existing
pipe supports may be located within the existing ordinary high water (OHW) level on each bank of
Rock Creek. Replacing these existing pipe supports will possibly require permits from both the U.S.
Army Corps of Engineers (USACE) and the Idaho Department of Water Resources (IDWR).
However, placing the pipe supports at a certain setback distance from OHW level would likely
reduce the permitting needed. Coordination would be required with the land owner during design
and construction, and a new easement would be likely be necessary because the new sewer route
does not match the existing alignment and may need to extend outside the existing easement.
The field that contains the existing aerial crossing is also designated by FEMA as a Zone AE 100-
year floodplain. Construction activities that involve excavation or fill would likely require floodplain
permitting at this location. The field is also dictated as a wetland by National Wetlands Inventory
(NWI). Excavation and fill placement in wetlands are regulated by USACE, and construction
activities would have to be verified to meet wetland permitting criteria and mitigation.
A cost for this alternative including future build out along Grandview Drive has been performed
on a per linear foot basis.
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B4-63
B4-64 B4-62
B4-65
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LIFT STATION
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RAILROAD
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Figure 3: Alternative 2 Replace Sewer Line from M1826 to M5528
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Alternative 3 — Replace and Re-locate sewer to eastbound lane in Highway 30
In this alternative,the existing sewer from manhole 134-66 to 134-6 would be removed and replaced
with a sewer main located in the eastbound Highway 30 travel lanes. The replacement sewer
would be upsized for future build-out. Figure 4 highlights the new sewer line route. The existing
sewer would be abandoned with portions of the sewer possibly removed from the field if
necessary. This alternative could also include an extension along Grandview Drive similar to as
shown in Figure 3 for Alternative 2.
The advantage of this alternative is that the existing aerial Rock Creek crossing and the above
ground sewer pipe is removed from the private property that is currently in use by the owner.The
sewer would also be located in a more accessible location for future development/connections
north of Highway 30. This alternative also likely reduces the permitting required for construction
within a floodplain and for an aerial creek crossing. There would also be no need for a structural
engineer to design new pipe supports.
The disadvantage of this alternative is the increased difficulty of installation due to existing road
base material, the existing Rock Creek culvert crossing, and increased traffic control measures
necessary for project construction. Construction costs involving landscaping removal and repair,
erosion and sediment control, and surface restoration and striping are also all factors for increased
cost and scope on this alternative.The elevation of this existing highway is significantly higher than
the elevation of the field containing the existing above ground sewer. The new sewer would
require trenching and shoring in the built-up rock and road base materials. Due to the steep
ground slope near Rock Creek, the sewer may also require steep pipe slopes in certain areas
between manholes in the area just south of Highway 30.
The existing Rock Creek crossing beneath Highway 30 would have to be evaluated. Knowledge of
the depth, material, and slope of the crossing would be required for the proposed sewer
installation within the eastbound lane. Separation requirements between Rock Creek and the
proposed sewer would have to be met. Existing sewer easements would also have to be revised
for this re-located sewer route.
A cost estimate has been prepared for this sewer relocation alternative.
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Lo
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Figure 4: Alternative 3 New Sewer within Highway 30
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Alternative -'Grandview Sewer Msion South
In this sub-alternative, the sewer main is extended to the south to service a larger area. The
replaced sewer line will be a larger diameter to accommodate the future build-out along
Grandview Drive. The City has not yet determined what pipe size will be ideal. See the table below
for a summary of the maximum flow capacities for each size of pipe at their minimum slopes (in
accordance with the Ten State Standards). The friction factor utilized for these calculations was
0.012. Population equivalent sizes were estimated from the flow assumption of 100 gpd per
person and a peaking factor of four.
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Pipe Size (in) Pipe Slope Pipe Flow Equivalent
NO Capacity (gpm) Population
size
8 0.40 399.7 1,439
10 0.28 606.4 2,184
12 0.22 874.1 3,148
15 0.15 1308.6 4,713
18 0.12 1903.3 6,856
The advantages of this extension sewer is the improved ability to handle future build-out.
Replacing and upsizing the pipe renews the life of the already aged sewer, and eliminates the
future replacement need over Rock Creek due to increased future demands.
Sewer to City Lot Alternative Summ
Alternative 1 — Reaching the City lot across Highway 30 would likely be too difficult to provide a
gravity sewer service. This is due to the distance south off the road of the existing sewer and the
distance required to reach the lot. Service to this lot would likely require pumping in this
alternative.
Alternative 2 — Reaching the City lot across Highway 30 is similar to Alternative 1.
Alternative 3 —The City lot could be serviced by a gravity sewer service that ties into the
proposed sewer located in the Highway 30 travel lane.
Construction Cost Estimate
Probable Class 4 construction costs have been estimated for the alternatives consistent with the
2013 CSMP methodology with updated unit costs for piping, surface restoration, installation
within the highway, and bypass pumping. The unit costs from the CSMP have been updated with
the January 2024 Engineering News Record Construction Cost Index of 13,515. Where CSMP unit
costs did not cover work required, project specific costs were determined. The requirements for
the trenchless highway crossing or installation can vary based on the Highway District
requirements. The probable total construction cost for the four alternatives is summarized in
Table 1 with both the high and the low-cost conditions. The probable cost breakdown is included
in Appendix C.
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Table 1
Probable Total Construction Cost
ConstructionAlternative Total .
(Estimated Variation Range=-15%to+25%)
1—Repair Damaged Sewer $344,000
2- Replace Damaged Sewer Crossing 8" $828,000
3— Replace to Highway 30
8" $997 Per LF
10" $1,024 Per LF
12" $1,053 Per LF
15" $1,082 Per LF
18" $1,133 Per LF
21" $1,167 Per LF
Grandview Sewer Extension South
8" $611 Per LF
10" $641 Per LF
12" $673 Per LF
15" $707 Per LF
18" $761 Per LF
21" $800 Per LF
Recommended Alt alive
The recommended alternative for solving the current condition is Alternative Number 1, Repair
Damaged Sewer line utilizing Cured-in-place piping (CIPP). This alternative is recommended
because it has a lower probable total construction cost and scope. This repair would maintain the
sewer and provide the City of Twin Falls time to scope, model and design a Grandview Sewer
replacement and extension in the future.
Alternatives 2 and 3 would provide the City with greater capacity and flexibility to operate the
collection system into the future. Alternative 2 allows for future build-out south without incurring
the possible inflated future construction cost. However, replacing the aerial crossing may already
be more difficult and costly to obtain proper permits for and construct within the existing
alignment. Alternative 3 allows flexibility by relocating the sewer within Highway 30 ROW, making
it more accessible for future development to the north of the highway. This also removes the
existing aging sewer from private property.
Replacing the existing sewer from manhole 134-66 to 134-6 with the same sized 8" diameter above
ground pipe size is not a recommended alternative in this analysis because the cost and difficulty
is so much higher than Alternative 1 without adding much in the way of benefits. The only
advantage would be a brand new pipe. This pipe would have to resist exposure to the elements
and it would not allow for future build-out capabilities. The existing structural pipe supports may
not be in a condition where they could be re-used with a new 8" pipe.
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Next Steps
The next step for this project is to discuss preferred alternatives and the path forward with the
City. After the preferred alternative is selected,the next step of the project is to begin final design.
This includes additional data collection both at the project site and in the office.The data collection
at the site includes a geotechnical investigation and survey in the area of the selected alternative.
The data collection in the office will include beginning coordination with the County, ITD and
landowners to ensure that the future design will be consistent with their requirements.
Appendix
Appendix A— Existing Condition photos
Appendix B—As-built drawings
Appendix C—Cost Estimates
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Appendix A
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Appendix B
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Appendix C
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�,\ consor
Probable Cost of Construction
Grandview Sewer Alternative Analysis -Alternative 1 - CIPP
Project: Grandview Sewer Alternative Analysis
Submittal: Alternative 1-CIPP
Owner: City of Twin Falls
ProjectNo.: W2320851D.00
Date: 2/7/2024
Unit Costs
Quantity Total Cost
Material Labor/Equipment Total
Al 8"Existing sewer CIPP Material 1,457 LF $100.00 $20.00 $120.00 $174,840.00
A2 8"Sewer bypass pumping 2 DAY $2,200.00 $3,400.00 $5,600.00 $11,200.00
A3 8"Sewer External Misc.repair 1 LS $3,000.00 $500.00 $3,500.00 $3,500.00
A4 8"Sewer Cleaning 1,457 LF $12.00 $12.00 $17,484.00
A5 Manhole Cleaning 6 EA $100.00 $400.00 $500.00 $3,000.00
A6 Clearing and Grubbing-Misc. 1-LS $500.00 $500.00 $500.00
A7 Landscaping repair-Misc. 1 LS 1 $200.001 1 $200.001 $200.00
A8 Traffic Control-Rural 1 LS $2,107.241 1 $2,107.241 $2,107.24
A9 ESC Control 1 LS $4,214.481 1 $4,214.481 $4,214.48
SubTotal: $217,045.72
Material&Labor Total: $217,045.72
Bonds and Insurance: 2% $4,341
Mobilization: 10% $21,705
State Revolving Fund(AIS,Prevailing Wage): 0% $0
Contractor's Overhead&Profit: 10% $21,705
Subtotal $264,796
Owner's Allowance/Contingency: 30% $79,439
Environmental Mitigation Not included
Right of Way Acquisition Not included
Estimated Construction Cost $344,000
Engineering 0% $0
Construction Eng./Admin. 0% $0
Estimated Proiect Cost $344,000
Construction Cost w/sales Tax and Owner's Allowance(minimum range:-15%) $292,000
Construction Cost w/sales Tax and Owner's Allowance(maximum range:+2591o) $430,000
Aj consor
Probable Cost of Construction
Grandview Sewer Alternative Analysis -Alternative 2 - 8" Replacement
Project: Grandview Sewer Alternative Analysis
Submittal: Alternative 2-8"Replacement
Owner: City of Twin Falls
ProjectNo.: W2320851D.00
Date: 2/7/2024
Item No.
Unit Costs
Quantity Total Cost
Material Labor Lipment Total
Al 8"PVC Installed w/bedding 4-10 feet deep 535 LF $55.00 $75.00 $130.00 $69,550
A2 8"PVC Installed above ground 925 LF $55.00 $25.00 $80.00 $74,000
A3 8"Sewer bypass pumping 10 DAY $2,200.00 $3,400.00 $5,600.00 $56,000
A4
Possible Exploratory Excavation Includinpotholing) 2 EA $1,000.00 $1,000.00 $2,000
A5 48"Manholes(4-1Oft deep) 5 EA $4,058.00 $4,058.00 $20,290
A6 External Above ground pipe casing 925 LF $50.00 $10.00 $60.001 $55,500
A7 Trench Rock 30%Length) 161 LF $125.00 $125.00 $20,063
A8 Dewaterin 535 LF $5.40 $5.40 $2,889
A9 MISC New Pipe support and brackets 1 LS $15,000.00 $6,000.00 $21,000.00 $21,000
A10 Aerial creek structure and support 1 LS $50,000.00 $50,000.00 $50,000
All Aerial Creek Pipe casing 80 LF 1 $100.00 $100.00 $8,000
Al2 Type P surface repair(Asphalt) 635 SY $70.00 $50.00 $120.00 $76,200
A13 Type C surface repair Gravel 250 SY $10.00 $5.00 $15.00 $3,743
A14 Paint Striping Repair 200 LF $6.00 $6.00 $1,200.00
A15 Flood lain and Wetland permitting and coordination 1 LS $5,000.00 $5,000.00 $5,000.00
A16 Clearing and Grubbing 1 LS $3,000.00 $3,000.00 $3,000.00
A17 Landscaping repair 1 LS $2,000.00 $2,000.00 $2,000.00
A18 ESC Control 1 LS $4,704.35 $4,704.35 $4,704.35
A19 Traffic Control-Rural 1 LS $9,408.69 $9,408.69 $9,408.69
SubTotal: $484,548
Material&Labor Total: $484,547.59
Bonds and Insurance: 2% $9,691
Mobilization: 10% $48,455
State Revolving Fund(AIS,Prevailing Wage): 0% $0
Contractor's Overhead&Profit: 10% $48,455
Subtotal $591,148
Owner's Allowance/Contingency: 30% $177,344
Environmental Mitigation 10% $59,115
Right of Way Acquisition Not included
Estimated Construction Cost $828,000
Engineering 0% $0
Construction Eng./Admin. 0% $0
Estimated Project Cost $828,000
Construction Cost w/sales Tax and Owner's Allowance(minimum range:-15%) $704,000
Construction Cost w/sales Tax and Owner's Allowance(maximum range:+25%) $1,035,000
Aj consor
Probable Cost of Construction
Grandview Sewer 8" Highway 30 Install - Alternative Analysis
Project: Grandview Sewer 8"Highway 30 Install
Submittal: Alternative Analysis
Owner: City of Twin Falls
ProjectNo.: W232085ID.00
Date: 2/7/2024
Item No.
Unit Costs
Quantity Total Cost
Material Labor/Equipment 1
L/E
Al 8"PVC Installed w/bedding in HWY 30 1,890 LF $55.00 $80.00 $135.00 $255,150
A2 8"Sewer bypass pumping 2 DAY $1,100.00 $1,700.00 $2,800.00 $5,600
A3 48"Manhole 10-16 FT De 8 EA $4,800.00 $0.00 $4,800.00 $38,400
A4 Possible Exploratory Excavation(Includinpotholing) 4 EA $1,000.00 $1,000.00 $4,000
A5 Trench Rock(60%Length) 1,134LF $130.00 $130.00 $147,420
A6 Dewatering 200 LF 1 $5.40 $5.40 $1,080
A7 MISC Utility crossing and site work 1 LS $10,000.00 $10,000.00 $10,000
A8 Type P surface repair(Asphalt) 3,900 SY $100.00 $60.00 $160.00 $624,000
A9 Type C surface repair(Gravel) 250 SY $10.00 $5.00 $15.00 $3,750
A10 5'Sidewalk re air 9 SY $120.00 $30.00 $150.00 $1,350.00
All Paint Striping Repair 800 LF $7.00 $7.00 $5,600.00
Al2 ITD ROW Permitting and coordination 1 LS $10,000.00 $10,000.00 $10,000.00
A13 Clearing and Grubbing 1 LS $2,000.00 $2,000.00 $2,000.00
A14 Landscaping repair 1 LS $2,000.00 $2,000.00 $2,000.00
A15 ESC Control 1 LS $22,207.00 $22,207.00 $22,207.00
A16 Traffic Control -Urban Heavy 1 LS 1 $55,517.501 1 $55,517.501 $55,517.50
SubTotal: $1,188,075
Material&Labor Total: $1,188,074.50
Bonds and Insurance: 2% $23,761
Mobilization: 10% $118,807
State Revolving Fund(AIS,Prevailing Wage): 0% $0
Contractor's Overhead&Profit: 10% $118,807
Subtotal $1,449,451
Owner's Allowance/Contingency: 30% $434,835
Environmental Mitigation Not included
Right of Way Acquisition Not included
Estimated Construction Cost $1,884,000
Engineering 0% $0
Construction Eng./Admin. 0% $0
Estimated Project Cost $1,884,000
Construction Cost w/sales Tax and Owner's Allowance(minimum range:-15%) $1,601,000
Construction Cost w/sales Tax and Owner's Allowance(maximum range:+2501o) $2,355,000
Aj consor
Probable Cost of Construction
Grandview Sewer 10" Highway 30 Install - Alternative Analysis
Project: Grandview Sewer 10"Highway 30 Install
Submittal: Alternative Analysis
Owner: City of Twin Falls
ProjectNo.: W2320851D.00
Date:2/7/2024
Item No.
Unit Costs
Quantity Total Cost
Material Labor Equipment Total
Al 10"PVC Installed w/bedding in HWY 30 1,890 LF $61.00 $90.00 $151.00 $285,390
A2 8"Sewer bypass pumping 2 DAY S1,100.00 $1,700.00 $2,800.00 $5,600
A3 48"Manhole 10-16 FT De 8 EA $4,800.00 $0.00 $4,800.00 $38,400
A4 Possible Exploratory Excavation(Includinpotholing) 4 EA $1,000.00 $1,000.00 $4,000
A5 Trench Rock(60%Length) 1,134 LF $130.00 $130.00 $147,420
A6 Dewaterin 200 LF 1 $5.40 $5.40 $1,080
A7 MISC Utility crossing and site work 1 LS $10,000.00 $10,000.00 $10,000
A8 Type P surface repair(Asphalt) 3,900 SY $100.00 $60.00 $160.00 $624,000
A9 Type C surface repair(Gravel) 250 SY $10.00 $5.00 $15.00 $3,750
A10 5'Sidewalk repair 9 SY $120.00 $30.00 $150.00 $1,350.00
All Paint Striping Repair 800 LF $7.00 $7.00 $5,600.00
Al2 ITD ROW Permitting and coordination I LS $10,000.00 $10,000.00 $10,000.00
A13 Clearing and Grubbing I LS $2,000.00 $2,000.00 $2,000.00
A14 Landscaping repair I LS $2,000.00 $2,000.00 $2,000.00
A15 ESC Control 1 LS $22,811.80 1 $22,811.80 $22,811.80
A16 Traffic Control -Urban Heavy 1 LS 1 $57,029.501 1 $57,029.50 $57,029.50
SubTotal: $1,220,431
Material&Labor Total: $1,220,431.30
Bonds and Insurance: 2% $24,409
Mobilization: 10% $122,043
State Revolving Fund(AIS,Prevailing Wage): 0% $0
Contractor's Overhead&Profit: 10% $122,043
Subtotal $1,488,926
Owner's Allowance/Contingency: 30% $446,678
Environmental Mitigation Not included
Right of Way Acquisition Not included
Estimated Construction Cost $1,936,000
Engineering 0% $0
Construction Eng./Admin. 0% $0
Estimated Project Cost $1,936,000
Construction Cost w/sales Tax and Owner's Allowance(minimum range:-1511o) $1,646,000
Construction Cost w/sales Tax and Owner's Allowance(maximum range:+2591o) $2,420,000
Aj consor
Probable Cost of Construction
Grandview Sewer 12" Highway 30 Install- Alternative Analysis
Project: Grandview Sewer 12"Highway 30 Install
Submittal: Alternative Analysis
Owner: City of Twin Falls
ProjectNo.: W232085ID.00
Date: 2/7/2024
Item No.
Unit Costs
milliL I Quantity Total Cost
Material Labor/Equipment
L/E
Al 12"PVC Installed w/bedding in HWY 30 1,890 LF $68.00 $100.00 $168.00 $317,520
A2 8"Sewer bypass pumping 2 DAY $1,100.00 $1,700.00 $2,800.00 $5,600
A3 48"Manhole 10-16 FT De 8 EA $4,800.00 $0.00 $4,800.00 $38,400
A4 Possible Exploratory Excavation(Includinpotholing) 4 EA $1,000.00 $1,000.00 $4,000
A5 Trench Rock(60%Length) 1,134LF $130.00 $130.00 $147,420
A6 IDewatering 200 LF $5.40 $5.40 $1,080
A7 MISC Utility crossing and site work 1 LS $10,000.00 $10,000.00 $10,000
A8 Type P surface repair(Asphalt) 3,900 SY $100.00 $60.00 $160.00 $624,000
A9 Type C surface repair(Gravel) 250 SY $10.00 $5.00 $15.00 $3,750
A10 5'Sidewalk repair 9 SY $120.00 $30.00 $150.00 $1,350.00
All Paint Striving Repair 800 LF $7.00 $7.00 $5,600.00
Al2 ITD ROW Permitting and coordination 1 LS $10,000.00 $10,000.00 $10,000.00
A13 Clearing and Grubbing 1 LS $2,000.00 $2,000.00 $2,000.00
A14 Landscaping repair 1 LS $2,000.00 $2,000.00 $2,000.00
A15 ESC Control 1 LS $23,454.40 1 $23,454.40 $23,454.40
A16 Traffic Control -Urban Heavy 1 LS $58,636.001 $58,636.00 $58,636.00
SubTotal: $1,254,810
Material&Labor Total: $1,254,810.40
Bonds and Insurance: 2% $25,096
Mobilization: 10% $125,481
State Revolving Fund(AIS,Prevailing Wage): 0% $0
Contractor's Overhead&Profit: 10% $125,481
Subtotal $1,530,869
Owner's Allowance/Contingency: 30% $459,261
Environmental Mitigation Not included
Right of Way Acquisition Not included
Estimated Construction Cost $1,990,000
Engineering 0% $0
Construction Eng./Admin. 0% $0
Estimated Project Cost $1,990,000
Construction Cost w/sales Tax and Owner's Allowance(minimum range:-15%) $1,692,000
Construction Cost w/sales Tax and Owner's Allowance(maximum range:+2501o) $2,488,000
Aj consor
Probable Cost of Construction
Grandview Sewer 15" Highway 30 Install- Alternative Analysis
Project: Grandview Sewer 15"Highway 30 Install
Submittal: Alternative Analysis
Owner: City of Twin Falls
ProjectNo.: W232085ID.00
Date: 2/7/2024
Item No.
Unit Costs
Quantity Total Cost
Material Labor/Equipment
L/E
Al 15"PVC Installed w/bedding in HWY 30 1,890 LF $75.00 $110.00 $185.00 $349,650
A2 8"Sewer bypass pumping 2 DAY $1,100.00 $1,700.00 $2,800.00 $5,600
A3 48"Manhole 10-16 FT De 8 EA $4,800.00 $0.00 $4,800.00 $38,400
A4 Possible Exploratory Excavation(Includinpotholing) 4 EA $1,000.00 $1,000.00 $4,000
A5 Trench Rock(60%Length) 1,134LF $130.00 $130.00 $147,420
A6 IDewatering 200 LF $5.40 $5.40 $1,080
A7 MISC Utility crossing and site work 1 LS $10,000.00 $10,000.00 $10,000
A8 Type P surface repair(Asphalt) 3,900 SY $100.00 $60.00 $160.00 $624,000
A9 Type C surface repair(Gravel) 250 SY $10.00 $5.00 $15.00 $3,750
A10 5'Sidewalk repair 9 SY $120.00 $30.00 $150.00 $1,350.00
All Paint Striving Repair 800 LF $7.00 $7.00 $5,600.00
Al2 ITD ROW Permitting and coordination 1 LS $10,000.00 $10,000.00 $10,000.00
A13 Clearing and Grubbing 1 LS $2,000.00 $2,000.00 $2,000.00
A14 Landscaping repair 1 LS $2,000.00 $2,000.00 $2,000.00
A15 ESC Control 1 LS $24,097.00 1 $24,097.00 $24,097.00
A16 Traffic Control -Urban Heavy 1 LS $60,242.501 $60,242.50 $60,242.50
SubTotal: $1,289,190
Material&Labor Total: $1,289,189.50
Bonds and Insurance: 2% $25,784
Mobilization: 10% $128,919
State Revolving Fund(AIS,Prevailing Wage): 0% $0
Contractor's Overhead&Profit: 10% $128,919
Subtotal $1,572,811
Owner's Allowance/Contingency: 30% $471,843
Environmental Mitigation Not included
Right of Way Acquisition Not included
Estimated Construction Cost $2,045,000
Engineering 0% $0
Construction Eng./Admin. 0% $0
Estimated Project Cost $2,045,000
Construction Cost w/sales Tax and Owner's Allowance(minimum range:-15%) $1,738,000
Construction Cost w/sales Tax and Owner's Allowance(maximum range:+2501o) $2,556,000
Aj consor
Probable Cost of Construction
Grandview Sewer 18" Highway 30 Install - Alternative Analysis
Project: Grandview Sewer 18"Highway 30 Install
Submittal: Alternative Analysis
Owner: City of Twin Falls
ProjectNo.: W2320851D.00
Date:2/7/2024
Item No.
Unit Costs
Quantity Total Cost
Material Labor Equipment Total
Al 18"PVC Installed w/bedding in HWY 30 1,890 LF $95.00 $120.00 $215.00 $406,350
A2 8"Sewer bypass pumping 2 DAY $1,100.00 $1,700.00 $2,800.00 $5,600
A3 48"Manhole 10-16 FT De 8 EA $4,800.00 $0.00 $4,800.00 $38,400
A4 Possible Exploratory Excavation(Includinpotholing) 4 EA $1,000.00 $1,000.00 $4,000
A5 Trench Rock(60%Length) 1,134 LF $130.00 $130.00 $147,420
A6 Dewaterin 200 LF 1 $5.40 $5.40 $1,080
A7 MISC Utility crossing and site work 1 LS $10,000.00 $10,000.00 $10,000
A8 Type P surface repair(Asphalt) 3,900 SY $100.00 $60.00 $160.00 $624,000
A9 Type C surface repair(Gravel) 250 SY $10.00 $5.00 $15.00 $3,750
A10 5'Sidewalk repair 9 SY $120.00 $30.00 $150.00 $1,350.00
All Paint Striping Repair 800 LF $7.00 $7.00 $5,600.00
Al2 ITD ROW Permitting and coordination 1 LS $10,000.00 $10,000.00 $10,000.00
A13 Clearing and Grubbing 1 LS $2,000.00 $2,000.00 $2,000.00
A14 Landscaping repair 1 LS $2,000.00 $2,000.00 $2,000.00
A15 ESC Control 1 LS $25,231.00 $25,231.001 $25,231.00
A16 Traffic Control -Urban Heavy 1 LS $63,077.50 $4- 63,077.50 $63,077.50
SubTotal: $1,349,859
Material&Labor Total: $1,349,858.50
Bonds and Insurance: 2% $26,997
Mobilization: 10% $134,986
State Revolving Fund(AIS,Prevailing Wage): 0% $0
Contractor's Overhead&Profit: 10% $134,986
Subtotal $1,646,827
Owner's Allowance/Contingency: 30% $494,048
Environmental Mitigation Not included
Right of Way Acquisition Not included
Estimated Construction Cost $2,141,000
Engineering 0% $0
Construction Eng./Admin. 0% $0
Estimated Project Cost $2,141,000
Construction Cost w/sales Tax and Owner's Allowance(minimum range:-1511o) $1,820,000
Construction Cost w/sales Tax and Owner's Allowance(maximum range:+2591o) $2,676,000
Aj consor
Probable Cost of Construction
Grandview Sewer 21" Highway 30 Install- Alternative Analysis
Project: Grandview Sewer 21"Highway 30 Install
Submittal: Alternative Analysis
Owner: City of Twin Falls
ProjectNo.: W232085ID.00
Date: 2/7/2024
Item No.
Unit Costs
Quantity Total Cost
Material Labor/Equipment
L/E
Al 2V PVC Installed w/bedding in HWY 30 1,890 LF $105.00 $130.00 $235.00 $444,150
A2 8"Sewer bypass pumping 2 DAY $1,100.00 $1,700.00 $2,800.00 $5,600
A3 48"Manhole 10-16 FT De 8 EA $4,800.00 $0.00 $4,800.00 $38,400
A4 Possible Exploratory Excavation(Includinpotholing) 4 EA $1,000.00 $1,000.00 $4,000
A5 Trench Rock(60%Length) 1,134LF $130.00 $130.00 $147,420
A6 Dewaterin 200 LF $5.40 $5.40 $1,080
A7 MISC Utility crossing and site work 1 LS $10,000.00 $10,000.00 $10,000
A8 Type P surface repair(Asphalt) 3,900 SY $100.00 $60.00 $160.00 $624,000
A9 Type C surface repair(Gravel) 250 SY $10.00 $5.00 $15.00 $3,750
A10 5'Sidewalk re air 9 SY $120.00 $30.00 $150.00 $1,350.00
All Paint Striping Repair 800 LF $7.00 $7.00 $5,600.00
Al2 ITD ROW Permitting and coordination 1 LS $10,000.00 $10,000.00 $10,000.00
A13 Clearing and Grubbing 1 LS $2,000.00 $2,000.00 $2,000.00
A14 Landscaping repair 1 LS $2,000.00 $2,000.00 $2,000.00
A15 ESC Control 1 LS $25,987.00 $25,987.00 $25,987.00
A16 Traffic Control -Urban Heavy 1 LS $64,967.501 $64,967.501 $64,967.50
SubTotal: $1,390,305
Material&Labor Total: $1,390,304.50
Bonds and Insurance: 2% $27,806
Mobilization: 10% $139,030
State Revolving Fund(AIS,Prevailing Wage): 0% $0
Contractor's Overhead&Profit: 10% $139,030
Subtotal $1,696,171
Owner's Allowance/Contingency: 30% $508,851
Environmental Mitigation Not included
Right of Way Acquisition Not included
Estimated Construction Cost $2,205,000
Engineering 0% $0
Construction Eng./Admin. 0% $0
Estimated Project Cost $2,205,000
Construction Cost w/sales Tax and Owner's Allowance(minimum range:-15%) $1,874,000
Construction Cost w/sales Tax and Owner's Allowance(maximum range:+2501o) $2,756,000
Aj consor
Probable Cost of Construction
Grandview Sewer 8" Extension - Alternative Analysis
Project: Grandview Sewer 8"Extension
Submittal: Alternative Analysis
Owner: City of Twin Falls
ProjectNo.: W2320851D.00
Date:2/7/2024
Item No.
Unit Costs
Quantity Total Cost
Material Labor Equipment Total
Al 8"PVC Installed w/bedding—10 feet deep 15,500 LF $55.00 $75.00 $130.00 $2,015,000
A2 Sewer bypass pumping 5 DAY $1,100.00 $1,700.00 $2,800.00 $14,000
A3 48"Manholes 4-1 Oft de 28 EA $4,058.00 $0.00 $4,058.00 $113,624
A4 48"Manholes 10-16ft Dee 3 EA $4,800.00 $4,800.00 $14,400
A5 Trench Excavation—10'-16'Deep 1,000 LF $25.00 $25.00 $25,000
A6 Trench Rock 30%Length) 4,650 LF $125.00 $125.00 $581,250
A7 Dewatering 15,500 LF $5.40 $5.40 $83,700
A8 Possible Exploratory Excavation Includinpotholing) 30 EA $1,000.00 $1,000.00 $30,000
A9 MISC unknown site or utility crossings 1 EA $50,000.00 $50,000.00 $50,000
A10 Type P surface repair(Asphalt) 21,815 SY $80.00 $50.00 $130.00 $2,835,926
All Type C surface repair Gravel 246 SY $10.00 $5.00 $15.00 $3,694
Al2 Paint Striving REPAIR 200 LF $6.00 $6.00 $1,200.00
A13 MISC permitting and coordination 1 LS $15,000.00 $15,000.00 $15,000.00
A14 Clearing and Grubbing 1 LS $8,000.00 $8,000.00 $8,000.00
A15 Landscaping repair 1 LS $7,000.00 $7,000.00 $7,000.00
A16 ESC Control I 1 LS $57,977.94 1 $57,977.94 $57,977.94
A17 ITraffic Control-Rural I 1 LS $115,955. 1 $115,955.89 $115,955.89
SubTotal: $5,971,728
Material&Labor Total: $5,971,728.20
Bonds and Insurance: 2% $119,435
Mobilization: 10% $597,173
State Revolving Fund(AIS,Prevailing Wage): 0% $0
Contractor's Overhead&Profit: 10% $597,173
Subtotal $7,285,508
Owner's Allowance/Contingency: 30% $2,185,653
Environmental Mitigation 0% $0
Right of Way Acquisition Not included
Estimated Construction Cost $9,471,000
Engineering 0% $0
Construction Eng./Admin. 0% $0
Estimated Project Cost $9,471,000
Construction Cost w/sales Tax and Owner's Allowance(minimum range:-1501o) $8,050,000
Construction Cost w/sales Tax and Owner's Allowance(maximum range:+25%) $11,839,000
Aj consor
Probable Cost of Construction
Grandview Sewer 10" Extension - Alternative Analysis
Project: Grandview Sewer 10"Extension
Submittal: Alternative Analysis
Owner: City of Twin Falls
ProjectNo.: W2320851D.00
Date:2/7/2024
Item No.
Unit Costs
Quantity Total Cost
Material Labor Equipment Total
Al 10"PVC Installed w/bedding—10 feet deep 15,500 LF $61.00 $85.00 $146.00 $2,263,000
A2 Sewer bypass pumping 5 DAY $1,100.00 $1,700.00 $2,800.00 $14,000
A3 48"Manholes 4-1 Oft de 28 EA $4,058.00 $0.00 $4,058.00 $113,624
A4 48"Manholes 10-16ft Dee 3 EA $4,800.00 $4,800.00 $14,400
A5 Trench Excavation—10'-16'Deep 1,000 LF $25.00 $25.00 $25,000
A6 Trench Rock 30%Length) 4,650 LF $125.00 $125.00 $581,250
A7 Dewatering 15,500 LF $5.40 $5.40 $83,700
A8 Possible Exploratory Excavation Includinpotholing) 30 EA $1,000.00 $1,000.00 $30,000
A9 MISC unknown site or utility crossings 1 EA $50,000.00 $50,000.00 $50,000
A10 Type P surface repair(Asphalt) 22,102 SY $80.00 $50.00 $130.00 $2,873,241
All Type C surface repair Gravel 250 SY $10.00 $5.00 $15.00 $3,743
Al2 Paint Striving REPAIR 200 LF $6.00 $6.00 $1,200.00
A13 MISC permitting and coordination 1 LS $15,000.00 $15,000.00 $15,000.00
A14 Clearing and Grubbing 1 LS $8,000.00 $8,000.00 $8,000.00
A15 Landscaping repair 1 LS $7,000.00 $7,000.00 $7,000.00
A16 ESC Control I 1 LS $60,831.58 1 $60,831.581 $60,831.58
A17 ITraffic Control-Rural I 1 LS $121,663. 1 $121,663.161 $121,663.16
SubTotal: $6,265,653
Material&Labor Total: $6,265,652.53
Bonds and Insurance: 2% $125,313
Mobilization: 10% $626,565
State Revolving Fund(AIS,Prevailing Wage): 0% $0
Contractor's Overhead&Profit: 10% $626,565
Subtotal $7,644,096
Owner's Allowance/Contingency: 30% $2,293,229
Environmental Mitigation 0% $0
Right of Way Acquisition Not included
Estimated Construction Cost $9,937,000
Engineering 0% $0
Construction Eng./Admin. 0% $0
Estimated Project Cost $9,937,000
Construction Cost w/sales Tax and Owner's Allowance(minimum range:-IS%) $8,446,000
Construction Cost w/sales Tax and Owner's Allowance(maximum range:+25%) $12,421,000
Aj consor
Probable Cost of Construction
Grandview Sewer 12" Extension - Alternative Analysis
Project: Grandview Sewer 12"Extension
Submittal: Alternative Analysis
Owner: City of Twin Falls
ProjectNo.: W232085ID.00
Date: 2/7/2024
Item No.
Unit Costs
oil& I Quantity Total Cost
Material Labor/Equipment
L/E
Al 12"PVC Installed w/bedding—10 feet deep 15,500 LF $68.00 $95.00 $163.00 $2,526,500
A2 Sewer bypass pumping 5 DAY $1,100.00 $1,700.00 $2,800.00 $14,000
A3 48"Manholes 4-10ft de 28 EA $4,058.00 $0.00 $4,058.00 $113,624
A4 48"Manholes 10-16ft Dee 3 EA $4,800.00 $4,800.00 $14,400
A5 Trench Excavation—10'-16'Deep 1,000 LF $25.00 $25.00 $25,000
A6 Trench Rock 30%Length) 4,650 LF $125.00 $125.00 $581,250
A7 Dewatering 15,500 LF $5.40 $5.40 $83,700
A8 Possible Exploratory Excavation Includinpotholing) 30 EA $1,000.00 $1,000.00 $30,000
A9 MISC unknown site or utility crossings 1 EA $50,000.00 $50,000.00 $50,000
A10 Type P surface repair(Asphalt) 22,389 SY $80.00 $50.00 $130.00 $2,910,556
All Type C surface repair Gravel 253 SY $10.00 $5.00 $15.00 $3,792
Al2 Paint Striping REPAIR 200 LF $6.00 $6.00 $1,200.00
A13 MISC permitting and coordination 1 LS $15,000.00 $15,000.00 $15,000.00
A14 Clearing and Grubbing 1 LS $8,000.00 $8,000.00 $8,000.00
A15 Landscaping repair 1 LS $7,000.001 $7,000.00 $7,000.00
A16 ESC Control 1 LS $63,840.21 $63,840.21 $63,840.21
A17 Traffic Control-Rural 1 LS $127,680.42 $127,680.42 $127,680.42
SubTotal: $6,575,542
Material&Labor Total: $6,575,541.86
Bonds and Insurance: 2% $131,511
Mobilization: 10% $657,554
State Revolving Fund(AIS,Prevailing Wage): 0% $0
Contractor's Overhead&Profit: 10% $657,554
Subtotal $8,022,161
Owner's Allowance/Contingency: 30% $2,406,648
Environmental Mitigation 0% $0
Right of Way Acquisition Not included
Estimated Construction Cost $10,429,000
Engineering 0% $0
Construction Eng./Admin. 0% $0
Estimated Project Cost $10,429,000
Construction Cost w/sales Tax and Owner's Allowance(minimum range:-15%) $8,865,000
Construction Cost w/sales Tax and Owner's Allowance(maximum range:+25%) $13,036,000
Aj consor
Probable Cost of Construction
Grandview Sewer 15" Extension - Alternative Analysis
Project: Grandview Sewer 15"Extension
Submittal: Alternative Analysis
Owner: City of Twin Falls
ProjectNo.: W2320851D.00
Date:2/7/2024
Item No.
Unit Costs
Quantity Total Cost
Material Labor Equipment Total
Al 15"PVC Installed w/bedding—10 feet deep 15,500 LF $75.00 $105.00 $180.00 $2,790,000
A2 Sewer bypass pumping 5 DAY $1,100.00 $1,700.00 $2,800.00 $14,000
A3 48"Manholes 4-1 Oft de 28 EA $4,058.00 $0.00 $4,058.00 $113,624
A4 48"Manholes 10-16ft Dee 3 EA $4,800.00 $4,800.00 $14,400
A5 Trench Excavation—10'-16'Deep 1,000 LF $25.00 $25.00 $25,000
A6 Trench Rock 30%Length) 4,650 LF $125.00 $125.00 $581,250
A7 Dewatering 15,500 LF $5.40 $5.40 $83,700
A8 Possible Exploratory Excavation Includinpotholing) 30 EA $1,000.00 $1,000.00 $30,000
A9 MISC unknown site or utility crossings 1 EA $50,000.00 $50,000.00 $50,000
A10 Type P surface repair(Asphalt) 22,819 SY $80.00 $50.00 $130.00 $2,966,528
All Type C surface repair Gravel 258 SY $10.00 $5.00 $15.00 $3,865
Al2 Paint Striving REPAIR 200 LF $6.00 $6.00 $1,200.00
A13 MISC permitting and coordination 1 LS $15,000.00 $15,000.00 $15,000.00
A14 Clearing and Grubbing 1 LS $8,000.00 $8,000.00 $8,000.00
A15 Landscaping repair 1 LS $7,000.00 $7,000.00 $7,000.00
A16 ESC Control I 1 LS $67,035.66 1 $67,035.66 $67,035.66
A17 ITraffic Control-Rural I 1 LS $134,071. 1 $134,071.33 $134,071.33
SubTotal: $6,904,673
Material&Labor Total: $6,904,673.35
Bonds and Insurance: 2% $138,093
Mobilization: 10% $690,467
State Revolving Fund(AIS,Prevailing Wage): 0% $0
Contractor's Overhead&Profit: 10% $690,467
Subtotal $8,423,701
Owner's Allowance/Contingency: 30% $2,527,110
Environmental Mitigation 0% $0
Right of Way Acquisition Not included
Estimated Construction Cost $10,951,000
Engineering 0% $0
Construction Eng./Admin. 0% $0
Estimated Project Cost $10,951,000
Construction Cost w/sales Tax and Owner's Allowance(minimum range:-1501o) $9,308,000
Construction Cost w/sales Tax and Owner's Allowance(maximum range:+25%) $13,689,000
Aj consor
Probable Cost of Construction
Grandview Sewer 18" Extension - Alternative Analysis
Project: Grandview Sewer 18"Extension
Submittal: Alternative Analysis
Owner: City of Twin Falls
ProjectNo.: W232085ID.00
Date: 2/7/2024
Item No.
Unit Costs
nil& I Quantity Total Cost
Material Labor/Equipment
L/E
Al 18"PVC Installed w/bedding—10 feet deep 15,500 LF $95.00 $115.00 $210.00 $3,255,000
A2 Sewer bypass pumping 5 DAY $1,100.00 $1,700.00 $2,800.00 $14,000
A3 48"Manholes 4-10ft de 28 EA $4,058.00 $0.00 $4,058.00 $113,624
A4 48"Manholes 10-16ft Dee 3 EA $4,800.00 $4,800.00 $14,400
A5 Trench Excavation—10'-16'Deep 1,000 LF S25.00 $25.00 $25,000
A6 Trench Rock 30%Length) 4,650 LF $125.00 $125.00 $581,250
A7 Dewatering 15,500 LF $5.40 $5.40 $83,700
A8 Possible Exploratory Excavation Includinpotholing) 30 EA $1,000.00 $1,000.00 $30,000
A9 MISC unknown site or utility crossings 1 EA $50,000.00 $50,000.00 $50,000
A10 Type P surface repair(Asphalt) 23,250 SY $80.00 $50.00 $130.00 $3,022,500
All Type C surface repair Gravel 263 SY $10.00 $5.00 $15.00 $3,938
Al2 Paint Striping REPAIR 200 LF $6.00 $6.00 $1,200.00
A13 MISC permitting and coordination 1 LS $15,000.00 $15,000.00 $15,000.00
A14 Clearing and Grubbing 1 LS $8,000.00 $8,000.00 $8,000.00
A15 Landscaping repair 1 LS $7,000.00 $7,000.00 $7,000.00
A16 ESC Control I 1 LS $72,246.12 1 $72,246.12 $72,246.12
A17 ITraffic Control-Rural I 1 LS $144,492. 1 $144,492.23 $144,492.23
SubTotal: $7,441,350
Material&Labor Total: $7,441,349.85
Bonds and Insurance: 2% $148,827
Mobilization: 10% $744,135
State Revolving Fund(AIS,Prevailing Wage): 0% $0
Contractor's Overhead&Profit: 10% $744,135
Subtotal $9,078,447
Owner's Allowance/Contingency: 30% $2,723,534
Environmental Mitigation 0% $0
Right of Way Acquisition Not included
Estimated Construction Cost $11,802,000
Engineering 0% $0
Construction Eng./Admin. 0% $0
Estimated Project Cost $11,802,000
Construction Cost w/sales Tax and Owner's Allowance(minimum range:-15%) $10,032,000
Construction Cost w/sales Tax and Owner's Allowance(maximum range:+25%) $14,753,000
Aj consor
Probable Cost of Construction
Grandview Sewer 21" Extension - Alternative Analysis
Project: Grandview Sewer 21"Extension
Submittal: Alternative Analysis
Owner: City of Twin Falls
ProjectNo.: W232085ID.00
Date: 2/7/2024
Item No.
Unit Costs
oil& I Quantity Total Cost
Material Labor/Equipment
L/E
Al 2 1"PVC Installed w/bedding—10 feet deep 15,500 LF $105.00 $125.00 $230.00 $3,565,000
A2 Sewer bypass pumping 5 DAY $1,100.00 $1,700.00 $2,800.00 $14,000
A3 48"Manholes 4-10ft de 28 EA $4,058.00 $0.00 $4,058.00 $113,624
A4 48"Manholes 10-16ft Dee 3 EA $4,800.00 $4,800.00 $14,400
A5 Trench Excavation—10'-16'Deep 1,000 LF $25.00 $25.00 $25,000
A6 Trench Rock 30%Length) 4,650 LF $125.00 $125.00 $581,250
A7 Dewatering 15,500 LF $5.40 $5.40 $83,700
A8 Possible Exploratory Excavation Includinpotholing) 30 EA $1,000.00 $1,000.00 $30,000
A9 MISC unknown site or utility crossings 1 EA $50,000.00 $50,000.00 $50,000
A10 Type P surface repair(Asphalt) 23,681 SY $80.00 $50.00 $130.00 $3,078,472
All Type C surface repair Gravel 267 SY $10.00 $5.00 $15.00 $4,010
Al2 Paint Striping REPAIR 200 LF $6.00 $6.00 $1,200.00
A13 MISC permitting and coordination 1 LS $15,000.00 $15,000.00 $15,000.00
A14 Clearing and Grubbing 1 LS $8,000.00 $8,000.00 $8,000.00
A15 Landscaping repair 1 LS $7,000.00 $7,000.00 $7,000.00
A16 ESC Control 1 LS $75,906.57 $75,906.57 $75,906.57
A17 Traffic Control-Rural 1 LS $151,813.13 $151,813.13 $151,813.13
SubTotal: $7,818,376
Material&Labor Total: $7,818,376.34
Bonds and Insurance: 2% $156,368
Mobilization: 10% $781,838
State Revolving Fund(AIS,Prevailing Wage): 0% $0
Contractor's Overhead&Profit: 10% $781,838
Subtotal $9,538,419
Owner's Allowance/Contingency: 30% $2,861,526
Environmental Mitigation 0% $0
Right of Way Acquisition Not included
Estimated Construction Cost $12,400,000
Engineering 0% $0
Construction Eng./Admin. 0% $0
Estimated Project Cost $12,400,000
Construction Cost w/sales Tax and Owner's Allowance(minimum range:-15%) $10,540,000
Construction Cost w/sales Tax and Owner's Allowance(maximum range:+2511o) $15,500,000
ATTACHMENT 4
City of
TWIN FAIA S Date: Monday, May 13, 2024
To: Honorable Mayor and City Council
°„ oQ From: Sam O'Leary, Staff Engineer
SPF, 1NC+
ACTION ITEM
Request:
Request to use wastewater reserves to fund a CIPP contract to repair a portion of failing sewer line which
includes an elevated crossing over Rock Creek near Addison Avenue West in the amount of$155,000.
Time Estimate:
5-10 Minutes for staff to present, with questions after.
Background:
Council previously approved investigation into solutions for the Grandview Rock Creek sewer main line
back in June of 2023. This elevated sewer crossing over Rock Creek near Addison Avenue West was
constructed back in the mid 1960's and has not been regularly maintained until recently. Due to the lack
of ownership documentation, it had not been clear who was responsible for this line. At this time, the
maintenance and preservation of the Grandview Rock Creek sewer line has been determined to be the
responsibility of the City.
Engineering Staff has worked closely with the wastewater collections department and reviewed the
alternatives analysis provided by Consor. Due to substantial deterioration of the line and increased
complications over the last year, it is imperative to provide a quick and efficient solution.
The request for $155,000 will cover the cost of completing the CIPP repair to approximately 800' of the
deteriorated line. This is noted as a 'temporary' solution that will get the pipe in condition to be regularly
maintained.
Approval Process:
A majority vote of the Council to approve the use of wastewater reserve funds to repair the discussed
sewer line.
Budget Impact:
This is an unbudgeted item. Staff will need to utilize wastewater reserve funds to finance the completion
of this CIPP repair.
Regulatory Impact:
NA
History:
NA
Analysis:
NA
Conclusion:
Staff recommends City Council authorize $155,000 from wastewater reserve funds to pay for the CIPP
repair to the Grandview Rock Creek sewer line crossing.
Attachments:
1. FlyingSewer_05082024
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