Because they ' re 150 $<| sep |> I get the feeling they ' ll just look into adding external safety features like more runoffs , more protection from their suits , or yes , track modifications , before actually doing any major changes to the bikes though . Unless if sth really bad happens closely on more than one occasion that makes them realise that no , it isn ' t just a freak accident caused by that particularly odd lean angle and corner speed that happened that one time at that one turn on that one track , but god I hope it won ' t have to come to that . <| sep |> Hey there man , I will do my best to help you out here . I ' m a bit of a novice on these things because I ' ve only been in the industry for about 2 years . Anyhow . So starting from scratch , I am going to pretend this river is flowing straight in the direction as shown , without the dam of course . 1 . To begin I would just excavate a pathway around where the dam will be built , we ' ll call this the work area . The pathway will just be a trench deep enough to reroute the water around your work area , we will call this path a tail water bypass . 2 . There are a lot of factors to take into account when we talk about the total lengthduration of the project . To give a very quick brief time , off the top of my head , I would say give your crew 1 week to excavate the bypass and begin excavating for the dam , add 1 week to finish excavating the dam then begin building wooden forms for the dam . Side note wooden forms have to be built in order to pour concrete for the damn to build your wall I would then add 1 more week to finish formwork and then begin pouring concrete for each dam wall . Finally give an additional week for concrete to cure , remove formwork , remove bypassrecompact the trench and site clean up . So allinall I would say this project should be no more than 34 weeks , tops . I was being very conservative . With a very experienced crew this job should be done in half the time . 3 . There are even more factors to consider when estimating a job . You will need figure out how much heavy machinery equipment you will need backhoe ? excavator ? mini ex ? Do you own these pieces of equipment or will you have to rent ? How much will it cost to rent , how much to refuel , how much for the operators ? You will also need to add in cost for labor work and even for your own cost which would be management team project manager , project engineer , superintendent , foreman . You will have 1 of each of these . You will also need to account for materials tools , fuel for truck , dust control , safety equipment like hardhatsvestsPPE , concrete , special inspections for soilconcrete , rebar for concrete reinforcement if needed . The concrete will be priced on cubic yards , so in your image I would just guess the volume 2 m x ? m x ? m Call around to some concrete companies ask for a quote . There are many types of different concrete mix designs so you can be creative with that . This is pretty much all I can think of off the top of my head . Feel free to ask questions .