Addendum 3 - Questions-Answers Sanitary Sewer Rehab IFB 37-24-023 6-14-24.pdf

WAYNE COUNTY PROCUREMENT DIVISION

INVITATION FOR BIDS

FOR

RVSDS SRF Project Plan:

Phases 2C/3C – Sewer Rehabilitation

CONTROL #37-24-023 ADDENDUM NO. 3

ADDENDUM ISSUE DATE: June 14, 2024

This Addendum is being issued prior to the acceptance of Bids to allow for the following questions to answers:

1. Regarding the CIPP specification, although it appears water/steam curing is an allowable method, the specification seems to lean toward UV curing. Please confirm that all three curing methods are approved for this project?

ANSWER: All 3 curing methods are allowable, as long as Contractor can demonstrate the finished product will meet or exceed the requirements outlined in the contract documents through testing at the Contractor’s expense.

2. Regarding Rehab Location 2: NHV 3-29-28 on Sheet 111, could you please confirm the scope to be rehabbed? Profile view shows 3 segments of 42” to be CIPP lined (252 LF total), but plan view only shows 1 segment (88 LF) and quantity summary at bottom states only 88 LF 42” CIPP. Please advise.

ANSWER: The scope will include lining from NHV3-29 to NHV 3-38, quantity and plans will be updated (see attached Revised Sheet 111 – Rehab Location 2: NHV 3-29-28).

3. Regarding Rehab Location 4: JC 3-21 on Sheet 113, could you please confirm the scope to be rehabbed? Plan view and profile view show a 42” to be rehabilitated, but the 42” pipe segment NHV 3-22-JC (42” x 428 LF) is not highlighted as such in the profile and this is a lump sum pay item so would like to confirm. Please advise.

ANSWER: The scope will include the 42” as shown on the plan view, profile view will be updated.

4. Regarding the CIPP scope, specification section 33 01 31 states the liner shall be glass reinforced pipe (GRP) liner. While we understand the desire to minimize host pipe inside diameter reduction, we feel standard felt liners will be beneficial in some portions of the project while also providing a cost-effective, structural solution. Will you please allow standard felt CIPP liners in addition to fiberglass reinforced liners?

ANSWER: Standard felt liners will be allowed as long as the final liner thickness will meet all requirements and not reduce the capacity of the pipe. Supplemental Addendum Table 1 is provided with this addendum which identifies the maximum cross section reduction that will be allowable in each interceptor arm. The Contractor shall to take into consideration and be responsible for any changes with installation, cure times, weight, and restrictions on capacity reduction in accordance with the contract documents. Any areas that are found to not meet the requirements shall be replaced at the Contractor’s expense.

a) If standard felt liners are allowed, we would suggest the following design parameters based on industry standards. Please advise.

i) Initial Flexural Strength = 4,500 psi

ii) Initial Flexural Modulus of Elasticity = 400,000 psi

ANSWER: The following minimum parameters shall be used for standard felt liners and the spec will be updated. The Flexural Modulus of Elasticity = 400,000 psi. An updated technical specification will be provided in Addendum #4.

5. For GRP CIPP liner design, the current parameters are above the industry standard and above values recommended by large CIPP manufacturers. Would you please consider revising the following parameters?

a. Initial Flexural Strength: Revise from 12,500 psi to 7,000 psi

b. Initial Flexural Modulus of Elasticity: Revise from 850,000 psi to 700,000 psi

c. Long Term Retention of Properties: Revise from 50% to 60%

ANSWER:

a. Yes, Initial Flexural Strength: Revise from 12,500 psi to 7,000 psi

b. Yes, Initial Flexural Modulus of Elasticity: Revise from 850,000 psi to 700,000 psi

c. No, Long Term Retention of Properties: Cannot be Revised from 50% to 60%.

6. Could you please provide the groundwater depth or elevation to be used in CIPP thickness design calculations?

ANSWER: The Contractor shall assume half the bury depth or the water level indicated on the soil borings, whichever is greater.

7. CIPP specification section 33 01 31, paragraph 3.01.B.2 mentions a plastic sheet 10 mil thick will be pulled into the host pipe to protect the liner. Please confirm this is for UV liner installation only and not required for inversion of standard felt/GRP liner.

ANSWER: In accordance with 33 01 31 the plastic shall be used to protect the liner while using a pull-in-place in the liner, if inversion is used then no plastic would be required.

8. As indicated in specification section 33 40 00 (Temporary Flow Diversion and Bypass Pumping), GIS files are available upon request. Could we please receive these files and/or access to the GIS system?

ANSWER: GIS files will not be shared during the bidding process; however, the awarded Contractor will be provided access to these files as needed.

9. Could you please provide available videos for review via share link/drive? We can provide a link to upload files or provide a physical hard drive, if needed.

ANSWER: A link will be provided for access to the available videos in Addendum #4.

10. Due to the possibility of these interceptors surcharging quickly during even a small rain event and the inability to bypass pump the additional wet weather flow due to backwater conditions (per spec section 33 40 00 paragraph 1.1.L), it will be risky for the contractor to install large diameter CIPP in some portions of the project in a relatively short weather window. To reduce this risk for both Owner and Contractor, alternative rehabilitation methods that also provide a cost-effective, structural solution such as Spray Applied Pipe Liner (Geopolymer) and/or Spiral Wound Liner (SPR) which are also allowed on other project sites (Rehab Locations 1, 3, 4, and 6) may be better suited in some scenarios. Would you please consider allowing any of these three rehabilitation methods (CIPP, SAPL/Geopolymer, or SPR) at the contractor’s discretion for the entire large diameter rehab lining scope (Bid Items 91-94, 54”-78” rehab)?

ANSWER: Alternative rehabilitation methods will be considered on a case-by-case basis and may or may not be approved depending on if the Contractor can submit a value engineering proposal for the specific locations with previous experience, costs, risk benefits, and any other offsetting cost or installation items. Please be aware the proposed rehabilitation shall maintain or improve the existing capacity of the pipe segment and the County reserves the right to reject any other proposed alternatives.

11. Please confirm this project is tax exempt, as indicated on IFB page 28, section 5.3.

ANSWER: Confirmed, Wayne County is tax exempt per Section 5.3.1 – Tax Excluded from Price.

12. IFB page 14, section 3.3 (Contract Term) currently states a contract term of one year, with six additional one-month extension options at the discretion of Wayne County. One year contract term may not be enough for the scope and magnitude of this project and would suggest a two-year term. Could you please clarify or confirm the contract time on this project?

ANSWER: Bidders must provide the proposed timeline per Section 5.5 – Response to Specifications/Scope of Work Requirements. Any exceptions to the specifications or Contract Term must be clearly identified in the Bid.

13. IFB page 18, section 4.5 (Bid Submission Requirements) states bids must be submitted electronically through BidNet Direct and “Bidders should provide the documents in a modifiable form (e.g., Microsoft Word or Excel), but have the option to also provide copies of any documents in a non-modifiable form (e.g. PDF) with the sole exception of any pricing which must be provided in Excel format, when an Excel Pricing Sheet is provided. Bidder’s failure to submit a bid as required may result in disqualification of such bid.” Will this submission of documents in a “modifiable form” remain a requirement, or will bidders be allowed to upload bid documents in PDF format, with the exclusion of the Excel Pricing Sheet?

ANSWER: Bidders are allowed to submit/upload bid documents in PDF format with the exclusion of the Excel Pricing Sheet (Appendix A).

14. Do you have an engineer’s estimate and/or budget available for this project?

ANSWER: No, a budget and engineer’s estimate are not readily available.

15. Due to the complexity and magnitude of this project, we request a minimum one week bid extension as well as a bid date other than a Monday to allow all bidders time to prepare responsible, competitive bids. Please advise.

ANSWER: The bid due date has been extended to 2PM local time (EST) on June 24, 2024 in Addendum #1.

16. Per spec section 33 40 00 (Temporary Flow Diversion and Bypass Pumping) paragraph

1.1.L, the system surcharges during wet weather. How much rainfall does it take for the system to surcharge? Also, how long does it typically take for the system to return to “normal” flow conditions following a rain event/surcharge?

ANSWER: Will vary based on location within the system and time of year.

17. Are there any specific end seals required for the CIPP scope?

ANSWER: No specific end seals, per 33 01 31, Both ends of the cured Liner shall be cut flush at the inlet and outlet points in the manhole and/or end section, and be sealed with an epoxy or resin mixture compatible with the Liner/resin system, providing a watertight seal. Sealing material and installation method shall be submitted and approved by the Engineer prior to start of construction. Hydraulic cements and quick-set cement products are not acceptable.

18. When we modify the Manholes or install shafts to install the liners. What is the high-water flood elevation that they need to raised to while we are working if they are left open for extended periods of time.

ANSWER: Will vary based on location within the system and time of year. On previous lining and manhole rehab projects in this system, temporary barrel sections were set to roughly 5’ above the ground elevation were suitable.

19. Do we need to stamped designs of our modifications to the pipe to install the liners?

ANSWER: Yes any modifications to the pipe shall have stamped designs.

20. Will you consider regular felt liners for this project instead of Reinforced liners?

ANSWER: See response to Question 4.

21. Can you extend the bid roughly 3 weeks to July 12, 2024, because of the complexity of the bid and the 4th of July holiday

ANSWER: See response to Question 15.

22. I would like to request the CCTV video for the following segments:

a. 66” dia CIPP-Pages 98-99 MH RVI 6-039 to MH RVI 6-30

b. 54” dia CIPP Pages 100-101 MH NHV 3-15 to NHV 3-01

c. 78” dia CIPP Pages 104-105 MH RVI 6-22 to RVI 6-013

d. 66” dia CIPP Page 106-107 MH NHV 2-32 to NHV 2-21

e. 60” dia CIPP Page 108-109 MH MR 1-16 to MH MR 1-11

f. Rehab Loc 1. Page 110 MH NHV 5A-46 to MH NVH 5A-45

g. Rehab Loc 2. Page 111 MH-NHV 3-29 to MH NHV 3-28

h. Rehab Loc 3.Page 112 MH NHV 3-24 to MH NHV 3-23

i. Rehab Loc 4. Page 113 MH RVI 6-42 to JC 3-21

j. Rehab Loc 5. Page 114 MH NHV 4A-08 to MH NHV 4A-07

k. Rehab Loc 6. Page 115 MH JC 2-35 to MH NHV 2-34.

ANSWER: See response to Question 9.

23. What ground water elevation should our liner design use. Please specify the level whether it is below the existing ground, at ground level or above it for the floods.

ANSWER: See response to Question 6.