B12_Questions_Answers_1_Water_Control_Structures_0001.pdf

• Q1) You are requesting quite a few 5’ wide weirs and headwalls that have only 24” diameter pipe. These are very large heavy structures that are made for 36”-60” pipe. I just want to confirm that you want these structures and not the 4’ wide structures that the Merced NWR would normally purchase for this diameter of pipe.

• A1) We have been measuring outside to outside. Yes, those are big structures and we are replacing our bigger structures, so we will keep the size as listed. Merced does have many 3' structures and have done that size in the past, so thank you for confirming

• Q2) You are requesting several 4’ wide weirs and headwalls with 24” diameter pipe. Based on past usage, I am thinking that these should be the 3’ wide weirs.

• A2) Correct, 4 solid walls weirs

• Q3) You are requesting 168 – 2x6x 5 ½” weir boards. I am assuming this is a typo and you meant 55 ½” as a 5 1/2” boards would be way too small and nothing more than fire kindling and a 5.5’ weir board are still the incorrect size for the weirs. Please see below for weir board sizes based on the weir size.

• A3) A typo instead of 5'" it should be 55". Looking at the correct sizes for each width let's correct that to the following

• Sixty four 2x6x55 ½” board

• One hundred thirty two 2x6x68 3/8” board

• Q4) I am also a little confused on your headwalls. Can you please clarify? Sometimes you say “water control weir without stub solid wall (headwall design)” or “ concrete water control weir headwall”- I don’t see any design specs in this solicitation. I know what I have done in the past, which is a weir with pipe and two solid weirs, one on each side of the weir with pipe. Please confirm that this is the case and that they are not a true headwall which is a slanted front.

• A4) The solicitation corresponds to each wall connected or associated to the weir and their location.

• Q5) If you can please clarify the solicitation as the delivery to the red barn they call out weirs with pipes and headwalls individually and then the other half of the solicitation where the delivery is to the maintenance shop is says “pre-cast concrete water control weir with 5’ stub of 24” ASS Series 95 plain end polyethylene pipe without headwall” and “pre-cast concrete water control weir with 5’ stub of 24” ASS Series 95 plain end polyethylene pipe with headwall” Can you please make the solicitation consistent so it is clear exactly the quantity of weirs and quantity of headwalls and exactly what you are looking for?

• A5) This is for our crews to better understand when they install the Water Control Structures. Meaning that if a weir doesn't have a headwall, there is no headwall need to be installed with that weir. If there is, then a headwall needs to be installed. When it refers to with headwalls, that means there will be an individual headwall with the weir.

• Q6) You are requesting 40” ADS Plain end pipe, unfortunately this does not exist. Polyethylene pipe goes 36” and then jumps to 42”. When you go to the 42” you will only be able to get it in watertite, they do not make it in plain end. I don’t see any structures with 42” pipe, I am not sure if you are tying into an existing structure or not. You can purchase 42” split couplers and mar mac couplers though if they are needed. An existing structure however would most likely have the male or female end of pipe sticking out and you could tie directly into that without any couplers.

• A6) Yes, if we can do 42' weirs then let's do it along with the 42” pipe and mar mac couplers. Upon, the information you gave me I think it is best making and doing a weir rather than adding on to a mis-matched size for weir that we might as well replace.