Q&A_10-25-18.pdf

WA RIDGE MAIN (1)

MAIN AVENUE ACCESS IMPROVEMENT

General

Technical Question Answer Date

1 X Are you requiring DR18 or DR14 C900 PVC pipe for the sewer FM?

Per CRWWD requirements, Polyvinyl chloride (PVC) pipe AWWA C900 or AWWA

C905, SDR 18

10/1/18

2 X Are you requiring restrained pipe joints on any of the C900 PVC sewer FM?

Per CRWWD requirements, Thrust forces in pressurized pipelines shall be restrained or anchored to prevent excessive movement and joint separation under all projected conditions. Thrust restraint shall be mechanically restrained joints.

10/1/18

3 X The plans call for (4) 4” ductile iron MJ 45 bends, are you requiring all the fittings on the sewer force main to be ductile iron or just those (4)?

Please clarify. The (4) each 4‐inch MJ 45 Bends shown on sheet H.1 are part of the Sanitary Sewer. Sanitary Sewer pipe and fitting are PVC according to Subsection 708.05.

10/1/18

4 X Clean‐out detail on sheet H‐8 calls for a (threaded plug 12” with 2” square nut)‐ are you requiring the clean‐out to be 12” diameter on a 4” sewer main?

This will be addressed in a forthcoming Amendment.

10/1/18

5 X Are you requiring restrained pipe joints on any of the 8” CL52 water main? Note 3 on sheet I.2 references a detail which shows minimum pipe joint restrained lengths near fittings, but it isn’t included in the plans or spec.

Yes, the contract does require joint restraint per City of Ridgefield Standards.

10/1/18

Check General or Technical

6 X Item numbers 62501‐0000 Line A1040 and 62501‐0000 Line A1060 refer to wetland and upland turf establishment. What are the seed type requirements for both of these line items?

Material requirements for Section 625 Turf Establishment are specified in Subsection 625.02.

10/1/2018

7 X Section 625.08 Mulching under 625. – Turf Establishment lists applying wood fiber or grass straw cellulose fiber mulch (at rate of 1500 lbs per acre), as well as applying bonded fiber matrix hydraulic mulch (at rate of 3000 lbs per acre). Is it up to the contractor to decide which type of mulch they use between these two options?

Yes, the bidder can elect to use either option

10/4/2018

8 X Clarification to my question A3 ‐ MJ fittings are typically made from Ductile Iron and restrained with Mega Lug retainer glands. You can’t get an MJ PVC fitting. So, my question was inquiring if you would accept MJ AWWA C153 Ductile iron fittings with Mega Lug restraints on all the fittings?

Comply with the CRWWD Manual as called for in the SCR’s.

10/4/2018

9 X Can the asphalt in the roadway be left onsite as fill?

Yes. Construct embankments according to Section 204. Dispose of unsuitable or excess material according to Subsection 204.14.

10/5/2018

10 X Will Line Item A1540 Mitigation, Streambed Materials be imported or salvaged from onsite materials?

See Subsection 703.18. 10/5/2018

11 X What work does Line Item A1560 – Mitigation, Wetlands Mitigation refer to?

See Subsection 101.02. The first three digits of a pay item number in the bid schedule identify the Section under which the work is performed. Pay item number 64706-1000 indicates work specified under Section 647.

10/5/2018

12 X Is there any maintenance or a maintenance period required for the plantings?

No. This will be addressed in a forthcoming Amendment.

10/5/2018

13 X 107.10(e)(6) – Does the archaeologist need to remain onsite for the duration all excavation and bank shaping listed in the specification?

Yes. As described in the SCR, “Excavation of the Gee Creek Culvert at station 65+11 as well as bank excavation and bank shaping of Gee Creek east of Main Avenue requires archaeological monitoring .” This is exclusive (only Gee Creek, only east of Main Avenue). There is no requirement for archeologist monitoring anywhere else on the project site.

10/10/2018

14 X 157.10 – Please confirm the diversion can only be a lined diversion ditch or bypass culvert. The specifications seem to not allow a pumped bypass.

Pump bypass is allowed. 10/10/2018

15 X 552.11(b)(6) – Notes ‘precast concrete manufacturing plant certified by the Precast/Prestressed Concrete Institute Plant Certification Program with a “B‐4 Prestressed Deflected‐Strand Bridge Beams (Superstructure)” certification’ is to be used.

What elements of the project are required to be cast by a precast plant carrying this certification?

Any precast elements of the Gee Creek structure require this certification.

10/10/2018

16 X 602.03(b)(5) – Notes the precast manufacturer is supposed to ‘submit at least two independently verified full scale load tests that confirm the design methodology of the proposed three sided arch structure.’ This is seen as an unrealistic expectation which precast manufacturers would not perform. Please remove this requirement.

This will be addressed in a forthcoming Amendment.

10/10/2018

17 X 602.03(e) – Are concrete footing and stem walls required to be cast‐in‐place? The specifications and plan set contradict each other. Plan sheet G.18 leaves the design of the footings and stem walls up to the manufacturer of the precast concrete culvert.

Footing, stem walls and wing can either be CIP or Precast. This is a contractor choice.

10/10/2018

18 X Drawing K.1 – Please clarify which bid item the contractor should utilize to capture costs involved with the excavation for the mitigation area, stated at 2,550 CUYD.

It is up to the bidder to determine how to structure their bid. The wetland mitigation excavation work is specified in Section 647.

The Section 647 pay items are full compensation for the work specified in that Section. See Subsection 109.05.

10/10/2018

19 X Please explain all the utility work that is currently being done along main avenue. I have been to the site 3 times now and have constructability concerns regarding the dewatering and shoring that will be required to install the proposed culvert. I see they are horizontally drilling utility approximately 4’ under the proposed subgrade for the new arch culvert. This will eliminate any possibility to use sheet pile for dewatering and or shoring for excavation at this location. Please provide plan locations of all new utility’s that will be installed between now and the proposed contract start date.

This will be addressed in a forthcoming Amendment.

10/10/2018

20 X Are we to include “use tax” in our proposal or will FHWA be paying retail sales tax to the State of Washington?

FHWA will not be paying sales taxes to the State of Washington. Include the cost of taxes in your bids. Compensation provided by the pay items is full payment for all costs. See Subsection 109.05.

10/10/2018

21 X I am having trouble opening the documents that have the “tin” extension can you change this to a PDF and repost.

No. The .tin files are only useable in their native format.

10/10/2018

22 X Sheet J.1 lists items other than conduit. For example transformer pads, pedestals, vaults and hand holds. They are listed “For information only” are these items the contractor’s responsibility to install?

Yes. See Plan Sheets J.2 through J.11, and Section 636. All of the work in the contract is the responsibility of the contractor unless it is assigned to others. See Subsection 101.01.

10/11/2018

23 X Regarding precast plant certification specified under Subsection 552.11(b)(6), there seems to be some confusion from precast concrete suppliers. Precast suppliers are under the impression the Precaster certification requirement for Gee Creek structure is outlined in 602.03. Please clarify.

This will be addressed in a forthcoming Amendment.

10/11/2018

24 X Looking for the gradation requirement for item 30202‐2000 Roadway Aggregate, Method 2 in the project specifications, plans, and FP‐14 but haven’t found it yet. Specifications Table 703‐2 for Aggregates lists Subbase and Base and Plan Sheet E‐1 with typical sections calls our Roadway Aggregate, Method 2. Question: Is there additional information in the Specifications, Plans, or FP‐14 that I’ve missed that will clarify this?

Yes. See Subsection 101.02. The first three digits of the pay item number in the bid schedule identify the Section under which the work is performed. See Subsection

302.02 in the FP‐14. Material requirements for Roadway Aggregate are specified in 703.06.

10/11/2018

25 X E‐43, 156.07 (K) states that the GC is to furnish Pilot Car, or flaggers, or both. A pilot car seems like a very efficient method for one‐lane traffic.

However there is no bid item for pilot car. Is the Pilot Car to be considered Incidental to the Traffic Control Bid Item 1300?

This will be addressed in a forthcoming Amendment.

10/12/2018

26 X Can flow rate information for Gee Creek be provided for designing the temporary diversion?

See hydraulics report posted as physical data.

10/12/2018

27 X E‐48 Diversion installation, calls for Cofferdams to isolate construction area. Page 10 of the Geotech Report, 3.3.2 states the need to dewater down 20’ for the installation of the Spread footings for the arch culvert. This seems to require the installation of a cofferdam structure. However Sheet G.5 and other corresponding sheets only show Temporary diversion berms on each end of the Arch Culvert to facilitate dewatering. If cofferdams are necessary is there any information as to placement or design? Are the cofferdams to be incidental to the Arch Culvert Item 640?

All work specified in Section 157 is paid for under the Section 157 pay items. We are preparing an Amendment to Section 157 to clarify the diversion work.

10/12/2018

28 X The Road Closure from 7/5/19 to 10/3/19 seems extremely short for the amount of work that needs to be completed in the closure. It also conflicts with In‐Water Work window stated on E‐16 107.10 as 6/15/2019 to 11/1/2019, which will require road closure to install a by‐pass culvert per E‐48 Diversion Installation. Is there information available for how the FHA determined the length of the road closure? And how the arch culvert and associated roadway fill, storm and sanitary utilities, and surface paving can be completed in less than 90 days?

We are preparing an Amendment to Section 157 to clarify the diversion work.

10/12/2018

29 X Item 64703‐3010 – Mitigation Rock Weir has a unit of measure of each. It is very difficult to evaluate the volume of rock required to make the weirs shown. Can this unit be changed to a weight measurement like riprap?

We prefer to keep the unit of measure per each.

10/17/2018

30 X Is there any material haul off required besides what’s located at and around the bamboo?

Yes. See Subsections 201.06 and 203.05. 10/17/2018

31 X I need some clarification on the guardrail specs on this one. The bid schedule Line A0920 guardrail system G4, Type 4, Class B steel posts, WSDOT type 31, but the specs call for powder coating all steel parts. Is the guardrail powder coated corten guardrail? And what would the thickness of galvanizing be?

Per 617, guard rail posts are allowed to be weathering steel or galvanized. If galvanized are used, then they must be powder coated per 725.22 for the portion of rail that is above finished grade. On the other hand, if a weather steel post is used, the portion of the rail below finished grade per 710.07 must be zinc‐coated.

Galvanization weight/ft2 is in AASHTO M 180.

10/19/2018

Does that mean we have an option of weathering steel for the type 31 guardrail also?

See Subsection 617.01(b).

33 I am working on providing a bid for the Ridgefield, WA Main Access Improvements project. Our software requires vectorized plan sets to perform the in house take off. I am using the Erosion control drawings F.2 through F.6.

Drawings F.2 and F.4 are not vectorized, while F.3 F.5 and F.6 are vectorized. Can I please get the vectorized drawings for F.2 and F.4 of the plan set?

Sorry, no. 10/19/2018

Item. 61202—0100 Line A0860. 4” sewer line.

Section 612 or 209 do not show asphalt patching as a material incidental to the sewer line installation on First Ave. Will asphalt used for patching be measured under item 40301‐ 0100 Asphalt Concrete Pavement, Type 1

The trench for sewer work and the patching of that trench is incidental to the 612 item. The notes on the plans direct the bidder to construct the trench per Clark County Standards. The standard trench and patching requirements are shown on Clark County standard drawing U3.

10/19/2019

35 X

Question #28 asked about the road closure duration as it related to the in‐Water Work window. Your response said that it would be addressed when Section 157 was revised with by amendment. Amendment #3 did not address the issue of the road closure duration. The issue at hand is the amount of time the contract allows for the road closure and how this affects the installation of the two culverts. In short, there is not enough time to complete the culverts, fills, utilities, sidewalks and paving in the three month period that has been allotted without heroic means. Can the road closure date be moved to the beginning of the in‐water work date to give the contractor additional time to complete this project?

The contract allows the contractor to work at the site prior to the road closure date under single lane traffic control. Much of the preparation work etc is anticipated to be started prior to the July 5th full road closure date. The contract requires the road back open to two way traffic by Oct 3rd. The in‐water work window is a fish regulatory issue that overlaps with single lane traffic control and full closure. The road closure will not be adjusted

10/23/2018

36 Amendment 3 includes new plan sheets showing what appears to be some (not all) of the utilities recently installed by others. We understand from Amendment 3 that these are to be temporary to facilitate construction of the project, however, the location of these temporarily relocated utilities , is directly within, and below, the footprint of the foundation rock layer for the support and installation of the culvert footings. This newly installed location(s) of these utilities is now in direct conflict with the installation of any conventional driven sheet steel coffer dam system that is or may become necessary in order to construct the work as shown. Is the design intent to be able to construct the project without cofferdams and dewatering measures that appear to be inherent in the nature of the work given the soils information, the general saturated conditions of the area, the configuration of the existing streams and waterways and the environmental regulations the contractor must comply with as a means of not interrupting or damaging the newly installed utilities?

The NW Gas line is the only line bored under the project. The gas line is at least 5 feet into the basalt layer along edge of existing road which is 5+ feet below the bottom of footing excavation at Gee Creek.

The power and phone line are placed along the C/E on the surface and span over Gee Creek. Diversion is required and can be accomplished per the 157 via pumping, alternate culvert, or channel, the method selected to dam the channel is a contractor selection, for footing excavation de‐ watering if necessary is performed under 208.

A review of Amendment 3 indicates that all references to dewatering have been entirely removed from the Bid Documents. Is the intent of Amendment 3 to portray the needs for dewatering of the work area as now no longer required or necessary and that only diversion of the creeks/streams and removal of surface ponded water and any nuisance runoff are to be controlled by the contractor as a basis for bid or is dewatering still an incidental item of work that we are to account for in our pricing?

When the stream is diverted, the isolated water needs to cleared of aquatic life per

157. Once cleared, any de‐watering required for footing excavation is covered under 208. 107 provide direction on discharge requirements

In spite of the language and changes in Amendment 3, If dewatering measures are still considered to be a contractor responsibility and if a unique way is found to install a cofferdam system or similar shoring/excavation protection system without interrupting the newly installed utilities, Amendment 3 indicates that we are to simply discharge our water to a vegetated buffer more than 100 lf from the active waterways or water bodies. Because rotary drilling techniques were used to determine the soil properties (see the bore logs and soils report) there is no good evaluation in the documents of groundwater conditions or what a contractor can expect, except for their own assumption based on local conditions and any experience in the specific area where the work is to be performed. Our experience in the area would indicate groundwater at or near the surface in the months when this excavation needs to begin on order to meet the schedule requirements. Based on that experience and the information in the soils report/bore logs there is a potential for enough hydrostatic head in the bottom of the excavation to create the potential for a boiling sand/gravel condition. In order to combat this issue it may become necessary for a tremie slab as much as 9 feet

Per Section 208, seal concrete is only required if the excavation cannot be pumped reasonably free of water, the Contractor is responsible for the mix design per Subsection 552.03. FHWA does not believe there is a great enough risk in placing the footing to specifically callout using seal concrete as we believe there are construction methods and timing that can be utilized to mitigate the need for seal concrete. If the Contractor believes that using seal concrete is the only method to achieve our desired result, then their bid should reflect that method.