biddoc.pdf

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REQUEST FOR PROPOSALS

STANLEY ROAD OVER EXCELSIOR DITCH CULVERT

REPLACEMENT PROJECT ALAMOSA COUNTY,

COLORADO

July 31, 2025

Alamosa County is soliciting proposals to perform the replacement of the Stanley Road Bridge over the Excelsior Ditch. The scope of services includes, but is not limited to, the removal of the existing bridge structure, the installation of a 12' by 6' concrete box culvert with a buried bottom slab, ancillary earthwork, and other miscellaneous construction items.

The proposal documents may be picked up at the Alamosa County Road & Bridge Department, 8663 County Road 109S, Alamosa, CO 81101 during the hours of 8:00 a.m. to 4:00 p.m., Monday through Thursday. The complete document is also available at www.alamosacounty.org.

Proposals must be received no later than 4:00 p.m. on September 21, 2026. Any proposal received after this time will not be considered and will be returned to the respondent unopened unless good cause is shown as determined by Alamosa County in its sole discretion.

Contact: Ronnie Medina, Alamosa County R & B, 8663 County Road 109S, Alamosa, CO 81101, 719-589-6262, ronnie.medina@alamosacounty.org

This RFP will be published in the Valley Courier.

http://www.alamosacounty.org/ mailto:ronnie.medina@alamosacounty.org

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REQUEST FOR

PROPOSAL PROJECT

DESCRIPTION

Please review the attached exhibits for the Scope of work:

• Alamosa County Stanley Road over Excelsior Ditch - 100% Plans

• Alamosa County Stanley Road over Excelsior Ditch - 100% Specs

• Alamosa County Stanley Road over Excelsior Ditch - 100% Cost

Estimate

Any required permits for projects will be obtained by Alamosa County, including but not limited to:

● Alamosa County Grading Permit

● Alamosa County Public Way Permit

● Alamosa County Floodplain Permit

● Approval for the work from the Excelsior Ditch Company

Inspections will be performed by Alamosa County.

All material, equipment, installation, or construction shall be in accordance with the latest edition of the Colorado Department of Transportation’s Standard specifications for Road and Bridge Construction (2025) latest updates.

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REQUEST FOR PROPOSALS INSTRUCTIONS TO RESPONDENTS

1. This Request for Proposals (“RFP”) will be non-exclusive. Alamosa County reserves the right to purchase supplies or services from other professionals.

2. Prospective bidders may attend the pre-bid conference, but it is not mandatory.

Perspective bidders are encouraged to perform a site visit prior to submitting their bid, however, there will be no individual showing of the project with the authorized Alamosa County Representative. The pre-bid conference will be held in person at 8:00 a.m. on August 27, 2026 in the Alamosa County Road and Bridge Building, 8663 County Road 109S, Alamosa, CO 81101. If you would like to join via Google meets, please notify Ronnie Medina and we will send a link.

3. All questions regarding this proposal must be in writing via email to Ronnie Medina, Alamosa County Engineer, ronnie.medina@alamosacounty.org with the Subject Line: “STANLEY/EXCELSIOR DITCH PROJECT.” Please call to verify receipt of your questions.

4. Questions pertaining to the project must be submitted no later than 4:00 p.m. on August 31, 2026. No additional questions will be accepted after the date and time referenced above unless good cause is shown as determined by Alamosa County in its sole discretion. Oral interpretations shall be of no force and effect. Addendum(s) with responses to written questions will be posted on Alamosa County website at https:// www.alamosacounty.org no later than 4:00 p.m. on September 3, 2026.

5. Proposals must be received via email, U.S. mail, FedEx, UPS, DHL, or and delivery to Alamosa County Road & Bridge Department, 8663 County Road 109S, Alamosa, CO 81101, ronnie.medina@alamosacounty.org, no later than 4:00 p.m. on September 21, 2026. Bids will be opened and read aloud during the September 23, 2026 Alamosa County Commissioners Meeting.

6. 1 copy of your proposal is required. If brochures or other supportive documents are requested, then it is required that 1 set be submitted with your proposal.

7. Alamosa County reserves the right, in its sole discretion, to reject any and all proposals submitted in response to this RFP or to waive or not waive informalities or irregularities in proposals received or RFP procedures. Alamosa County also reserves the right to re-advertise or to otherwise provide the services as determined by Alamosa County to be in its best interest, to accept any portion of a proposal deemed to be in the best interests of Alamosa County to do so, or to further negotiate cost, terms or conditions of any proposal determined by Alamosa County to be in its best interests.

8. Alamosa County may, at its sole discretion, modify or amend any and all provisions herein. If it becomes necessary to revise any part of the RFP, addenda will be provided through posting at www.alamosacounty.org. Alamosa County reserves the right to extend the RFP submittal date or to postpone the award of an agreement.

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9. All proposals will be reviewed by a selection committee or any other review as determined to be necessary. Respondents may be asked to supplement their initial proposals with additional written material. Alamosa County may short-list respondents based upon an evaluation of the written submittals. Alamosa County may arrange for in-person interviews with the short-listed respondents for a detailed presentation.

10. The selected proposal will be the one considered the most advantageous regarding price, quality of service, qualifications and capabilities of respondent to provide the specified service, respondent’s familiarity with Alamosa County, and any other factors the County may consider as determined by Alamosa County in its sole discretion.

11. Respondents are encouraged to clearly identify any proprietary or confidential data or information submitted with the proposal. Regardless of whether or not so marked, Alamosa County will endeavor to keep that information confidential, separate, and apart from the proposal. Notwithstanding the foregoing, respondents acknowledge that Alamosa County may be required to release the information in accordance with the Colorado Open Records Act, order of the court, or other applicable law.

12. Alamosa County will not pay for any information requested herein, nor is it liable for any costs incurred by the respondent in connection with its response to this RFP.

13. No work shall commence nor shall any invoices be paid until the successful respondent has entered into a fully executed agreement with Alamosa County and provides the requested proof of insurance.

14. No telephone or oral proposals will be accepted.

15. Proposals must be clearly identified by the subject line or on the front of the envelope by proposal title. Responsibility for timely submittal of proposals lies solely with the respondent. Proposals received after the closing time specified will not be considered unless good cause is shown as determined by Alamosa County in its sole discretion.

16. Respondent(s) who submit a proposal are responsible for becoming fully informed regarding all circumstances, information, laws, and any other matters that might, in any way, affect the respondent’s role and responsibilities. Any failure to become fully knowledgeable shall be at the respondent’s sole risk. Alamosa County assumes no responsibility for any interpretations made by respondents on the basis of information provided in this RFP or through any other source.

17. All respondents must include a fully executed Proposal Form with their proposal.

18. Alamosa County reserves the right to award an agreement to the respondent that demonstrates the best ability to fulfill the requirements of the project based upon the County’s evaluation of the selection criteria.

19. This RFP is not intended to completely define the contractual relationship to be

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20. Upon identification by Alamosa County of the successful respondent, Alamosa County will give the successful respondent the first right to negotiate an agreement acceptable to Alamosa County. In the event that an agreement satisfactory to Alamosa County cannot be reached, Alamosa County may enter into negotiations with one or more of the remaining respondents. Alamosa County may choose to discard all proposals and re-issue another RFP.

19. The successful respondent(s) shall comply with the following bond and insurance language which shall be included in the agreement to be awarded unless otherwise agreed to in writing by Alamosa County:

“PERFORMANCE AND OTHER BONDS

CONTRACTOR shall furnish performance and payment bonds, each in an amount at least equal to the Contract Price as security for the faithful performance and payment of all CONTRACTOR’S obligations under the Contract Documents. These bonds shall remain in effect at least until two years after the date of final payment, except as otherwise provided by law. CONTRACTOR shall also furnish other bonds as are required by the Contract Documents. All bonds shall be executed by such sureties as (a) are licensed to conduct business in the state of Colorado, and (b) are named in the current list of “Companies Holding Certificates of Authority as Acceptable Sureties on Federal Bonds and as Acceptable Reinsuring Companies” as published in Circular 570 (amended) by the Audit Staff Bureau of Accounts, U.S. Treasury Department. All bonds signed by an agent must be accompanied by a certified copy of the authority to act.

If the surety on any bond furnished by CONTRACTOR is declared bankrupt, or becomes insolvent, or its right to do business is terminated in the state of Colorado , CONTRACTOR shall within five days thereafter substitute another bond and surety, both of which shall be acceptable to OWNER.

INSURANCE:

CONTRACTOR’S Liability Insurance: The CONTRACTOR shall purchase and maintain such insurance as will protect it from claims set forth below which may arise out of or result from the CONTRACTOR’S operations under the Agreement, whether such operations be by itself, or by any subcontractor, or by anyone directly or indirectly employed by CONTRACTOR or any subcontractor, or by anyone for whose acts any of them may be liable.

All such insurance shall remain in effect until final payment, and at all times thereafter when CONTRACTOR may be correcting, removing, or replacing defective work, CONTRACTOR shall maintain such completed operations insurance for at least two years after final payment, and furnish OWNER with evidence of continuation of such insurance at final payment and one year thereafter.

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Claims under Worker’s Compensation, disability benefits, and other similar employee benefit acts; Claims for damage because of bodily injury, occupational sickness or disease, or death of its employees, and claims insured by usual personal injury liability coverage; Claims for damage because of bodily injury, sickness or disease, or death of any person other than its employees, and claims insured by usual personal injury liability coverage; and Claims for damages because of injury to or destruction of tangible property, including loss of use resulting therefrom.

Worker’s Compensation insurance shall provide coverage as required by the laws of the State of Colorado.

Insurance covering claims for damages to persons or property required by the preceding paragraph shall be in the following minimum amounts:

If any aggregate limit is reduced below $1,000,000 because of claims made or paid, CONTRACTOR shall immediately obtain additional insurance to restore the full aggregate limit and furnish to OWNER a certificate or other document satisfactory to OWNER showing compliance with this provision.

Said insurance shall be furnished in types specified as follows:

CONTRACTOR’S Commercial General Liability Insurance issued to and covering the liability for damage imposed by law upon the CONTRACTOR and each Subcontractor with respect to all Work performed by them under the Agreement and covering premises operations, fire damage, independent contractors, products and completed operations, blanket contractual liability, personal injury, and advertising liability.

CONTRACTOR’S Protective Liability Insurance issued to and covering the liability for damages imposed by law upon the CONTRACTOR and each Subcontractor with respect to all Work under the Agreement performed for the CONTRACTOR by Subcontractors.

Bodily Injury Liability: Each Person: $1,000,000 Each Accident or Occurrence: $2,000,000

Property Damage Liability: Each Accident or Occurrence: $1,000,000

Aggregate: $2,000,000

Products and completed operations aggregate $1,000,000

Employers Liability, including Occupational Disease $500,000

Any one fire $50,000

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Completed Operations Liability Insurance issued to and covering the liability for damage imposed by law upon the CONTRACTOR and each Subcontractor arising between the date of final cessation of the Work, and the date of final acceptance thereof out of that part of the Work performed by each.

Comprehensive Automobile Insurance covering any auto (including owned, hired and non-owned autos) shall be carried with a minimum limit of $1,000,000.00 each accident combined single limit. All liability and property damage insurance required hereunder shall be Comprehensive General and Automobile Bodily Injury and Property Damage form of policy.

Employer’s Liability Insurance covering all of CONTRACTOR’s and any Subcontractor’s employees acting within the course and scope of their employment.

CONTRACTOR shall in addition, and in the amounts required under the above, obtain Protective Liability Insurance issued to and covering the liability for damages imposed by law upon the OWNER with respect to all operations under the Agreement by the CONTRACTOR or its Subcontractors, including omissions and supervisory acts by the

OWNER.

Comprehensive Risk Policy Option: In lieu of the several policies specified for CONTRACTOR’S Liability Insurance, a comprehensive liability and property damage insurance policy inclusive of all the insurance and requirements hereinafter set forth, with an umbrella covering of $2,000,000, subject to the approval of the OWNER, will be permissible.

Subcontractor’s Insurance: Before permitting any of its Subcontractors to perform any Work under this Agreement, CONTRACTOR shall either (a) require each of its Subcontractors to procure and maintain during the life of its Subcontracts, Subcontractor’s Public Liability and Property Damage Insurance of the types and in the amounts as may be applicable to its Work, which type and amounts shall be subject to the approval of the OWNER, or (b) insure the activities of CONTRACTOR’S Subcontractors in its own policy.

Builder’s Risk Insurance: CONTRACTOR shall procure and maintain, for the duration of the Work of this Project, Builder’s Risk Insurance, including the perils of fire, extended coverage (loss due to vehicles, explosion, wind, flood, riot, etc.), vandalism and malicious mischief, and special extended coverage (loss due to falling objects, collapse, water damage from faulty or leaking systems, etc.) in the full amount of the Contract Price plus the cost of authorized extras. Said amount of insurance coverage shall be considered to cover the insurable value of the Work under this Agreement which is considered not to exceed one hundred percent (100%) of the amount of this Agreement and authorized extras.

Such policy shall not insure any tools or equipment, or temporary structures erected at the site and belonging to any person or persons, or their Subcontractors who are obliged by contract with the OWNER to do Work on the Projects.

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Such insurance shall be placed jointly in the names of the OWNER, CONTRACTOR, and any and all Subcontractors, and any and all others obliged by contract with the OWNER to do Work on this Project and at the OWNER’s option, any other person or persons whom the OWNER deems to have an insurable interest in said property, or any part thereof, payable as their several interests may appear.

CONTRACTOR shall furnish OWNER with certification of said insurance prior to commencement of any Work. Any proceeds obtained from insurance provided for by this paragraph shall be paid to and held by the OWNER as trustee. The OWNER shall have the right to withhold payment of such proceeds until such time as the Work destroyed or damaged and covered by such insurance shall be reconstructed and shall pay such proceeds on an installment basis similar to that provided for by progress payment covering the original Work.

Certificates of Insurance: Certificates of Insurance acceptable to the OWNER shall be provided to the OWNER for attachment to the Agreement. These Certificates shall contain provisions naming the OWNER as an additional insured under CONTRACTOR’S insurance, as more fully required by the General Conditions herein, and that coverage afforded under the policies will not be cancelled until at least thirty days prior written notice has been given the OWNER. CONTRACTOR and its Subcontractors shall not permit any of its Subcontractors to start Work until all required insurance has been obtained and certificates with the proper endorsements have been filed with the OWNER. Failure of the CONTRACTOR to comply with the foregoing insurance requirement shall in no way waive the OWNER’S rights hereunder.

Owner’s Liability Insurance: The OWNER, at its option, may but shall not be required to purchase and maintain such liability insurance as will protect it against claims which may arise from operations under this Agreement. Purchasing and maintaining such insurance, however, will not relieve the CONTRACTOR from purchasing and maintaining the insurance hereinbefore specified.

Loss of Use of Insurance: The OWNER, at its option, may but shall not be required to, purchase and maintain such insurance as will insure it against loss of use of OWNER’S property due to fire or other hazards, however caused.

Coverage required of CONTRACTOR and any of its Subcontractors shall be primary over any insurance or self-insurance program carried by OWNER.

All insurance policies in any way related to this Agreement and secured and maintained by CONTRACTOR shall include clauses stating that each carrier shall waive all rights of recovery, under subrogation or otherwise, against Owner, its members, managers, agencies, institutions, organizations, officers, agents, employees, and volunteers. OWNER shall be named as additional insured on the Commercial General Liability, Automobile Liability Insurance, and Completed Operations Liability Insurance policies.

CONTRACTOR shall insert a clause in all contracts or sub-contracts, and all

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Subcontractors shall purchase and maintain the insurance on the terms and conditions as set forth herein.

Further, the successful respondent(s) shall comply with the following indemnification language which shall be included in the agreement to be awarded:

“To the fullest extent permitted by law, CONTRACTOR shall defend, indemnify, and hold harmless OWNER and ENGINEER, and their officials, agents, and employees, from and against all claims, damages, liabilities, losses, and expenses including, but not limited to, attorney’s fees and costs arising out of, or resulting from, the performance or non-performance of the Work, and including, but not limited to, claims, damages, liabilities, losses, or expenses attributable to bodily injury, sickness, disease, or death, or to injury to or destruction of tangible property, including the loss of use resulting therefrom or is caused, in whole or in part, by any negligent act or omission of CONTRACTOR, any Subcontractor, anyone directly or indirectly employed by any of them, or anyone for whose acts any of them may be liable. Nothing in the Contract Documents shall be interpreted so that the OWNER or ENGINEER waives its sovereign immunity granted under Colorado Governmental Immunity Act.”

PROPOSAL SUBMITTAL REQUIREMENTS

1. Proposal Form. Must be signed and submitted with response.

2. Qualifications. Briefly explain your company’s qualifications to provide the services requested, e.g., years in business, staffing, vehicles to be utilized, and experience.

3. Experience. Demonstrate past experience working on similar projects of the same size, scope, and complexity.

4. Schedule. Provide a construction schedule which details the start date and duration in days for the “Major Work Item” listed in the Scope of Services. The construction schedule should demonstrate all “Major Work Items” completed and deliverables to be presented to Alamosa County. Excelsior Ditch is closed between mid-November to April 1. All work within the ditch shall be within the closure period.

5. Budget/Pricing. Provide itemized cost estimate based on the estimated quantities listed in the plan set.

6. Familiarity with Alamosa County. Provide a narrative describing familiarity with Alamosa County.

7. References. Please provide three (3) references from current customers receiving the same or similar service(s). Include name of entity, contact name and telephone number.

8. Legal Issues. Are there any lawsuits, federal, state or local tax liens, or any potential claims or liabilities against you, your company or the officers of the company at this time or within the last three years? If so, please explain.

9. Deliverables. Deliverables will include:

● Product certification information, if applicable.

● Test reports, if applicable.

● Final calculated quantities

● Approval of As-Built drawings

10. Evaluation Criteria. Evaluation criteria will include the lowest, qualified bid, experience with projects of similar scope, ability to meet the project schedule, and familiarity with Alamosa County.

REQUEST FOR PROPOSAL FORM

THIS PROPOSAL FORM MUST BE SUBMITTED WITH YOUR PROPOSAL

TO:

Ronnie Medina Alamosa County Road and Bridge 8663 County Road 109S Alamosa, CO 81101

Re: STANLEY ROAD over EXCELSIOR DITCH REPLACEMENT PROJECT The undersigned, having examined the Instructions to Respondents and any and all documents related to the above referenced RFP:

(a) Agrees to comply with all conditions, requirements, and instructions of the Request for Proposal as stated or implied therein;

(b) Acknowledges the right of Alamosa County, Colorado in its sole discretion to reject any or all proposals submitted, and that an award may be made to a respondent even though not the lowest cost;

(c) Acknowledges and agrees that the discretion of Alamosa County, Colorado in selection of the successful respondent(s) shall be final, not subject to review or attack; and

(d) Acknowledges that this proposal is made with full knowledge of the foregoing and full agreement thereto.

By submission of this proposal, and signature below, the respondent acknowledges that the respondent has the authority to sign this Proposal Form and bind the company named below.

The respondent further acknowledges that Alamosa County, Colorado has the right to make any inquiry or investigation it deems appropriate to substantiate or supplement information contained in the proposal and related documents, and authorizes release to Alamosa County of any and all information sought in such inquiry or investigation.

Company Name:

Title of Respondent:

Signature of Respondent:

GTE

IR

IR

SCALE IN FEET

10 20

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2.5 5

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2.5 5

AutoCAD SHX Text

%%UELEVATION

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AutoCAD SHX Text File Name: 91601_ST-00STLYRD-003B_Inspection_Sketch.dwg

AutoCAD SHX Text Print Date: 6/30/2026

AutoCAD SHX Text 27'-10 "14"

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AutoCAD SHX Text Stanely Road

AutoCAD SHX Text N County Rd 102

AutoCAD SHX Text 149°38'40"

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AutoCAD SHX Text 20'-0 " - Abut18" - Abut

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AutoCAD SHX Text Gravel over 4" Corrugated Steel Deck

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ST-00STLYRD-003B

12076 Grant Street Thornton, CO 80241 Ph: (303) 962-9300 Fax: (303) 962-9350

N

AutoCAD SHX Text R:\Q-PROJECTS\ACTIVE PROJECTS\91601_ALAMOSA COUNTY STANLEY ROAD OVER EXCELSIOR DITCH\800_COMPUTER DESIGN FILES\802_SHEET FILES\B-02 GENERAL LAYOUT.DWG

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RockSol Consulting Group, Inc.

12076 Grant Street, Thornton, CO 80241 Ph 303.962.9300 Fax 303.962.9350 Web www.rocksol.com

Memorandum To: Ronnie Medina, Alamosa County Engineer From: Derek Adams, PE, Bridge Engineer, RockSol Janaye Boardwell, PE, Assistant Roadway and Hydraulics Engineer, RockSol Subject: Alamosa County Stanley Road over Excelsior Ditch – Hydraulic Memorandum Date: September 12, 2025

This memorandum has been prepared to show the project hydraulic criteria, describe the existing hydraulic conditions, and discuss proposed improvements for the Alamosa County Stanley Road over Excelsior Ditch bridge replacement project. This project includes replacement of the existing bridge with a concrete box culvert due to corrosion section loss of steel structural elements.

Existing Conditions

At the project location, Excelsior Ditch flows from northwest to southeast under a single-span bridge with a low chord elevation of 7591.95 feet on the upstream end and 7591.88 feet on the downstream end.

Existing bridge superstructure consists of 8” thick gravel driving surface over a steel corrugated deck supported by 14” deep steel girders. The bridge is at a 60-degree skew from the ditch and provides a hydraulic opening of about 5 feet tall by 10.5 feet wide measured perpendicular to the channel. An aerial view of the bridge crossing is shown below.

adams Adams CO PE Stamp adams Typewritten Text 9/18/25

Alamosa County Stanley Road over Excelsior Ditch – Hydraulic Memorandum

A drop structure, located about 40 feet downstream of the bridge, controls the flow through this reach under typical flow conditions. The concrete structure consists of a 20-ft long constriction with a 1-ft drop and a 2.5-ft weir (see photo below).

Under intended conditions, the ditch typically conveys a flow of about 30 cubic feet per second (cfs), with potential to achieve up to 90 cfs under high flow operating conditions. A maximum potential flow of 130 cfs is assumed in the case of a storm event concurrent with full irrigation discharge. The photo below shows the downstream side of the existing bridge at typical flow conditions (about 30 cfs).

A 1-D hydraulic model was created using HEC-RAS 6.6 to represent the flow under these three conditions. Cross sections of the ditch were created from survey data of the reach approximately 230 feet upstream and 210 feet downstream of the Stanley Road bridge. The following Manning’s roughness coefficients were used.

Channel: 0.025 (earth, clean, some gravel) Sides/Floodplain: 0.035 (pasture, some high grass) Roadway: 0.030 (gravel) Drop Structure: 0.017 (finished concrete with gravel bottom) Proposed Concrete Box Culvert: 0.013 (finished concrete) Existing Abutment Walls: 0.030 (corrugated metal)

The results of this analysis include water surface elevation (WSEL) and freeboard for the existing bridge, provided below. Per CDOT Drainage Design Manual, freeboard and reported WSEL values are determined based on a cross-section 30 feet upstream of the existing bridge.

Flow (cfs) WSEL (ft) Depth at center of channel (ft)

Freeboard (ft)

30 7590.18 3.23 1.77 90 7591.34 4.39 0.61

130 7591.99 5.04 -0.04

The following cross-section shows the three existing WSELs (blue lines) relative to the bridge deck on the upstream side (facing southeast/downstream).

The existing structure provides adequate hydraulic capacity for typical flow conditions.

Proposed Conditions

The proposed culvert at Stanley Road is a 12-ft by 6-ft concrete box with an upstream low chord that matches the existing bridge upstream low chord of 7591.95 feet. The box culvert bottom slab will be buried to provide a hydraulic opening of about 5-ft to match the existing structure. The proposed culvert was sized to match or slightly exceed the hydraulic capacity of the existing bridge. A 1-D HEC-RAS model was created to model this structure, producing the following results. These values are taken from the same upstream location as the existing bridge results.

Flow (cfs) WSEL (ft) Depth at center of channel (ft)

Freeboard (ft)

30 7590.18 3.12 1.77 90 7591.33 4.38 0.62

130 7591.99 5.04 -0.04

A cross-section of the upstream side of the bridge deck and proposed WSELs (blue lines) is shown below.

The following is a profile view of the modeled reach. Flow is from right to left, with the blue lines representing WSEL at each of the three flows.

Summary

The existing single span Stanley Road over Excelsior Ditch bridge is proposed to be replaced with a 12-ft by 6-ft concrete box culvert with a buried bottom slab. Proposed structure was found to nearly match the hydraulic capacity of the existing bridge. The following table compares existing and proposed hydraulic conditions under Sullivan Road at a flow rate of 90 cfs. Note that the channel velocity values are taken from the bridge entrance.

WSEL

(ft)

Depth at center of channel (ft)

Freeboard (ft)

Upstream structure channel velocity (ft/s)

Existing Bridge 7591.34 4.39 0.61 2.24 Proposed Culvert 7591.33 4.38 0.62 1.73

References

Colorado Department of Transportation, 2019, Drainage Design Manual

Colorado Department of Transportation, February 2023, Bridge Design Manual

ITEM DESCRIPTION UNIT QUANTITY UNIT COST

PRICE

201-00000 Clearing and Grubbing* LS 1 -$

202-00155 Removal of Wall* LF 68 -$

202-00220 Removal of Asphalt Mat* SY 43 -$

202-00401 Removal of Bridge (Special)* EA 1 -$

202-01130 Removal of Guardrail Type 3* LF 144 -$

203-00060 Embankment Material (Complete In Place)* CY 50 -$

203-01500 Blading* HOUR 50 -$

206-00000 Structure Excavation CY 340 -$

206-00100 Structure Backfill (Class 1) CY 169 -$

206-00200 Structure Backfill (Class 2) CY 58 -$

207-00700 Topsoil (Onsite) CY 80 -$

208-00002 Erosion Log Type 1 (12 inch) LF 200 -$

208-00035 Aggregate Bag LF 150 -$

208-00046 Pre-Fabricated Concrete Washout Structure (Type 1) EA 1 -$

208-00075 Pre-fabricated Vehicle Tracking Pad* EA 1 -$

208-00103 Removal and Disposal of Sediment (Labor)* HOUR 20 -$

208-00105 Removal and Disposal of Sediment (Equipment)* HOUR 20 -$

208-00106 Sweeping (Sediment Removal)* HOUR 20 -$

208-00300 Temporary Berms* LF 100 -$

210-00810 Reset Ground Sign* EA 5 -$

211-03005 Dewatering LS 1 -$

212-00032 Soil Conditioning ACRE 0.1 -$

212-00706 Seeding (Native) Drill ACRE 0.1 -$

213-00012 Spray-On Mulch Blanket ACRE 0.1 -$

304-06000 Aggregate Base Course (Class 6) TON 200 -$

515-00120 Waterproofing (Membrane) SY 153 -$

601-03030 Concrete Class D (Box Culvert) CY 140.7 -$

602-00000 Reinforcing Steel LB 28,319 -$

602-00020 Reinforcing Steel (Epoxy Coated) LB 12,107 -$

606-00302 Guardrail Type 3 (31 Inch Midwest Guardrail System) LF 163 -$

606-01385 Transition Type 3J EA 1 -$

606-01390 End Anchorage Type 3K EA 1 -$

606-02003 End Anchorage (Nonflared) EA 3 -$

607-11525 Fence (Plastic)* LF 100 -$

625-00000 Construction Surveying LS 1 -$

626-00000 Mobilization LS 1 -$

630-00000 Flagging* HOUR 600 -$

630-00007 Traffic Control Inspection* DAY 30 -$

630-00012 Traffic Control Management* DAY 60 -$

630-80335 Barricade (Type 3M-A)(Temporary)* EACH 1 -$

630-80337 Barricade (Type 3M-C)(Temporary)* EACH 3 -$

630-80341 Construction Traffic Sign (Panal Size A)* EACH 11 -$

630-80342 Construction Traffic Sign (Panal Size B)* EACH 14 -$

630-80360 Drum Channelizing Device* EACH 30 -$

630-80380 Traffic Cone* EACH 75 -$

700-70010 F/A Minor Contract Revisions FA 1 40,000.00$ 40,000.00$

COST ESTIMATE OF CONSTRUCTION BID ITEMS $40,000

*Items marked with an * will be performed by Alamosa County Road and Bridge.

Bid Tab Stanley Road Box Culvert

Alamosa County

July 24, 2026