Setting a drainage elevation THROUGH a high hill

[DM22]

THANKS to EVERYONE above who has offered their input and advice! All points well taken. (except one point about using perforated pipe...not sure why that even came up???) Sorry i stepped away from this thread for a week or so, but I was actually back at the site preparing Lake Leaky for her repair!! Installing and pumping her out with a natural siphon, which is another whole interesting thread I would like to do. I have plenty of pictures!!

Concerning ALL of your advice, I was successfully in business for myself (Manufacturing/Wholesale to the Home Center industry) for 30 years and was very fortunate in my businesses early growth years to have had 2 very important older gentlemen in my life who mentored me for years and kept my business (and personal) decision making on the right track. One was my first building landlord, who I guess needed to make sure I could pay him each month!!! And the other was my father-in-law, who just wanted to make sure I was successful so I could provide for his daughter!!! But all joking aside, trust me when I say, I seek out and value experience and advice from those who have been there and done that!! Listening to smart and experienced people like all of you, is exactly why I am very fortunate to have a "Lake Leaky" and the "Big Boy Toys" to play with trying to fix it!!

As I said, I was back at the site all last week and in looking it over again, the "benching" of the trench in stages is definitely on the table now. In fact, it will not require that much benching, only on the crown of the hill, due to the gentleness of the uphill sloping. So basically, very little DEEP digging.

In answering some of the questions brought up, NO, it wont disrupt or be a problem "robbing" water from someone elses drainage downstream, as it all drains to the same place on my property, even after passing through Lake Leaky. The size pipe will be either 12" or 15". No need for a larger diameter, as our plan is to build a sufficient size dam in the source ravine at the intake so the water can just pool up and then drain out into the lake at whatever pace it wants to. Basically like a water retention pond which is now required in almost all developments here in the south.

RANDY88, thank you for your very valuable insight and information. But I would like to hear your reasoning or purpose for the 90 degree turn at the start of the intake drainage.

Thanks again to everyone and we will work safe and smart!! But first priority is making sure Lake Leaky becomes "Lake Tight as a Frogs Ass"!!!

 

[DM22]

FYI: My original post is also under GENERAL INDUSTRY QUESTIONS. That is where I was answering some questions, such as pipe diameter, and was I robbing water from someone downstream!! Sorry for any confusion.

 

[Randy88]

DM22, I have no real idea as to what direction your coming into the valley with your pipe, around here, we use intakes for allowing water into the tile or pipe whatever term you want to use for the line, the reason for my idea was this, we usually come up the hollow or ravine so to speak, and then set the intake 90 degrees to the line and then build a small berm or terrace and that way the water's no quite so likely to follow the line down the hill around the pipe, the water has to pool and literally change direction to follow the line, now if your going into the ravine from across the side of the hill and your line is already 90 degree's to the waters natural flow of the valley, then your fine, again I was just guessing by your description you gave.

Also when using intakes, your line is in the ground about 4 feet at the berm, so take that into account when figuring your elevation difference between the intake end and the outlet end of the line. I'm not sure by your post if your planning on using an intake or not, I'd recommend using one, and not just an open line coming into the berm for the water to go down, like some use as an intake on ponds, again this depends on how much depth the water will be in the berm for the intake.

I didn't catch the perf pipe thing, but I'd use solid tubing, never perf for this application, otherwise if for some reason you have a plugged outlet or extreme pressure in the line, it'll wash the dirt away from around the pipe when it actually pressurizes the line and forces the water out through the perforations and liquify the dirt around the pipe, I've seen them literally walk the pipe out of the ground and spit it out on top the ground as it blows the structure out with it.

I'm not sure what type of laser or measuring instrument your using, but if you don't have your question answered about the level laser and how to use it to do this job, let me know, I'll attempt to talk you through it, but be prepared, it gets complicated and using a slope laser is far easier and faster and less chance to make a mistake.

 

[DM22]

Randy88, yes, we are coming in at 90 degrees to the drainage valley. And as previously mentioned, a dam or berm of adequate size will be constructed ACROSS the ravine bottom to pool or hold all of the water until it discharges out (90 degrees) through the pipe. Our plan is to NOT make a fixed intake. The point at which the pipe will begin is relatively flat in the ravine bottom, and it is at that elevation the bottom of the pipe will be set. In other words the pipe bottom or opening is going to be resting on the ravine bottom and then be sloped accordingly as it is dug into the hill. We will take your very valuable advice and put in a plate or "anti-seep" collar about 25 feet or so into the hill or after we have at least 5 or 6 feet of fill over the pipe. Concerning the pipe opening, we already have plans to install a metal guard out in front of and over the top of the intake pipe to prevent critters from getting in AND to prevent debris from clogging it up. This is a dry valley and only gets water runoff in a significant rain. I have purposely went into the ravine during a very heavy extended rain period to see the flow rate through the valley. It had just a good steady flow of water that I believe a 12" or 15" pipe will handle easily.

The "Perforated" pipe comment was brought up in the General Industry's Questions section. I am still perplexed as to why it was brought up???? WHY would someone even entertain using perforated pipe in the first place for a water "redirecting" situation???? Hell, i'm looking for all the water i can get, not looking to lose some along the way!!!!

I will be using a laser level. It does not have the sloping feature. After reading everyone's comments about that subject, I think our best option using what we have will be to just keep positioning the lazer to where we can shoot each end of the pipe as it is put in place. Each section of pipe is 24 feet long. My goal is "approximately" 1/4" of slope per foot. But for ease of calculations on each shot, at every 24 feet, we just need to make sure each elevation shot is at least 6 inches LOWER than the previous shot. Does that make sense? Please keep in mind this is not a critical or inspection required project. As long as the slope has some downhill fall, we will be good.

HOWEVER, as I said earlier, I love experienced advice and I WILL SPEAK with you if this gets complicated. Thanks for the offer!!

 

[Oxbow]

As mentioned before DM22, if you can calculate the total fall between the inlet and outlet, then divide that by 24' you will know how much to drop each pipe joint. You should be steep enough to make fine adjustments as you come close to your final joint. Just make sure that you always have a bit of slope on each joint and never have a reverse slope or you will encounter an air lock.

Have fun and be safe!

 

[tuney443]

A bit off topic but I wonder how my Dad would perceive all this ''fancy'' stuff.He used to brag that with his $4K old David White he could pin point the balls on a gnat at 1,000' and he would bust my balls for not trying to be as ''accurate.''I never wanted to use or inherit[I do still have it and others after he passed] his transit so one time on a sewer main using my little $200 or so level,after I ran app. 300' of 8'' SDR,he comes over unannounced,does the 10 minute[chasing the regular level bubble plus the bullseye one around--fun]typical DW setup--tells me AND the city's engineer that I'm off.The engineer says ''by how much?'' My Dad--''he's off by 1/4'',if this was my job it would be perfect.'' Engineer walked away laughing and I could only shake my head.True story.Miss my Dad.

 

[Randy88]

DM22, sorry for the confusion on the pipe installation, I didn't know what direction you line was coming into the valley at. As for why some would do perf pipe, you'd be surprised what some do the first time till they find out what happens over time.

As for your laser level and having to use then a rod and receiver and do the math, we've done plenty of what your doing with nothing more than a hand level and my made up stick to check with, take a couple of straight boards, about 12 feet long, set them on edge, and the top one being level, and the lower one being on grade you set up,screw them together with some boards to keep them the right distance apart, just do the math as to how much lower one end needs to be than the other, and when your on grade, your hand level is level on the top board, using the bottom board to determine if your trench bottom is flat as you go,it'll look like a small wedge shape when done, just a suggestion to simplify the operation some, do as you please.

About your pipe inlet end, I've done them as you described, but quit them years back, not telling you what to do, just telling you why I quit doing them that way, so don't take it the wrong way. We prefer the intakes for several reasons, first the main line is in the ground at least 3-4 feet, allowing one to clean the berm out without worrying about hitting the main line, and also by having the line deeper than the open end starting at ground level, it seems to not wash the line out as badly over time, and also it gives the opportunity to stack intakes with smaller holes on the bottom and larger towards the top, to allow dirt to settle in the basin and not go directly into the line, as the dirt depth gets deeper you can add to the top, if with an open pipe, either you have a basin that's lower to hold some water before going into the pipe and is alway wet, or silted in or all dirt goes into the line, not allowing settle out. Also with an open line, if or when the water depth gets deeper than the line, or gets clogged up with debris, you have a smaller total surface area for water to go into the line, with an intake, the surface area is greater, around the entire line, times more depth of intake. If water would ever go over the line, it'll create a swirl affect to get into the line, along with air needed, the largest problem we've seen with just an open ended line is debris floating over the line plugging it up, the total surface area on an intake helps to solve some of this, whats the difference, to the contractor nothing, to the owner, a lot, meaning if it plugs with debris, it'll wash out the berm and cause line problems, causing the owner to have to redo the upper end of the project, keeping in mind your close in elevation to the anti seep collar when needing to redo the berm, rather than buried deeper with an intake. The other big problem we see is in order for the line to not crush, you need at least 3 feet of dirt over the line, on the outlet end its not a big deal, people tend to remember its shallow, that and its usually wet and they stay away form the outlet end it seems, but when working with any equipment on the intake end, someone always ends up forgetting its too shallow to carry any weight and ends up getting crushed by something, a tractor, dozer, excavator, skid steer or whatever. Again, do as you please.

 

[DM22]

Randy88, all good points and well taken. Dirt washing into the pipe is a factor to consider. Would you by any chance have pictures of the INTAKES you suggest?

Also, great idea on the 12' straight edge boards and a level. I totally get that and how it works. However, I do not want to put anyone at risk going into the ditch and risk cave ins. Even with the amount of benching I have to do, the ditch will still be to deep to risk going into. So I will do the extended stick and receiver. I just happen to have a very light weight 1 1/4" aluminum pipe 16" long. So I will attach it to my regular surveying stick with the receiver on it.

 

[Barry van Riel]

Hi there,
I came across this forum by chance.I have a small company in New Zealand ,and we specialise in civil and construction products which includes a range of laser and machine control instruments.An inexpensive solution may be as simple as a smart level with a laser pointer which will give you percentage and degrees as the distance isn't great.If you have Robotoolz in the states,they do a very simple manual grade laser which has vials for set up and would be suitable for short range of 3-400ft.These are rotating and come with reciever,and you can do a manual offset in 2 axis.The model is an RT3620-2.Either of these might give you a quick fix without too much cost.

 

[Oxbow]

A bit off topic but I wonder how my Dad would perceive all this ''fancy'' stuff.He used to brag that with his $4K old David White he could pin point the balls on a gnat at 1,000' and he would bust my balls for not trying to be as ''accurate.''I never wanted to use or inherit[I do still have it and others after he passed] his transit so one time on a sewer main using my little $200 or so level,after I ran app. 300' of 8'' SDR,he comes over unannounced,does the 10 minute[chasing the regular level bubble plus the bullseye one around--fun]typical DW setup--tells me AND the city's engineer that I'm off.The engineer says ''by how much?'' My Dad--''he's off by 1/4'',if this was my job it would be perfect.'' Engineer walked away laughing and I could only shake my head.True story.Miss my Dad.

There is nothing wrong with the old equipment, and accurate as can be. I have seen survey points in the forest that were put there in the days of older transits and chains that are dead on. Today gps is still non-functional in a forest, and a total station is very time consuming as you have to turn so many times and at the end of the day tying back into an original point many busts occur.

 

[Randy88]

DM22, just google or look up the website, hickenbottominc.com and you should get to their website, there are some others out there too, precision intakes is another, they come in three pieces, a t shaped bottom that hooks to the line, and a middle section that has smaller holes in it that's buried in the ground to the top of it, and the top which has larger holes in it that stands up above the ground. Now they can be sawed off at whatever height you want to really, hickenbottoms have a place to cut the sections in half, whereas precision intakes every six inches there's a place to cut them and they'll still fit together. Some others are out there too, I'd avoid the steel ones, only use those made of three pieces of plastic, that way when something snaps the top off, you can just put it back in, with the steel one's, they are one piece and when you or something else bends them or hits them, you have to dig the entire thing up to replace it or fix it.

The government only approved of the steel intakes in my area for decades for terracing projects, and every farmer everywhere hates the metal one's with a passion, replacing the metal one's with plastic three piece units have been job security for many years.

 

[Randy88]

DM22, I know its not my business, but curiosity is getting to me on this question, if your putting in that large of line in the first place, your at the bottom of the drainage area anyhow, why not just do the cut through the hill, use the fill from the cut to use as a ditch plug in the valley your diverting water from and forget the line completely.

 

[DM22]

Randy88, per you first post, I will go look at the INTAKE websites. Thanks for that info.

DM22, I know its not my business, but curiosity is getting to me on this question, if your putting in that large of line in the first place, your at the bottom of the drainage area anyhow, why not just do the cut through the hill, use the fill from the cut to use as a ditch plug in the valley your diverting water from and forget the line completely.

Hey........it is "your business", cause I am asking you to get involved!!! Beggars cant complain. No offense taken here at all!

Concerning just cutting a ditch, the "HILL" that we are ditching through is actually a large food plot that parallels the lake. So my deer would not be happy with me if I cut a permanent ditch through their dinner table!!! Plus, it also has an access road on top of it that is a main access to other parts of the property. So then I would have to build a bridge. And it would need to be able to handle my 160 Excavator on down.

Thanks for your input.

 

[Randy88]

DM22, Ok, I understand now, if there's anything else I can help you with, let me know.

 

[DM22]

Thanks Randy, you have been a great help already.

 

[watglen]

randy88, thanks for the tip on the precision inlets. I have long thought the hickenbottom design was a pain because the height was never right. Cutting every 4 or 6 inches too much sense.

If learning tips and tricks is your thing, this website is the place to be!

 

[DM22]

Sorry Randy88, one more question. Why do you suppose the available INTAKES you suggested are only limited to smaller diameter pipes? I looked at the sites you recommended, and I think I only saw one company with a diameter of up to 12" max. What is being used in larger diameter pipe situations? I am thinking of using a 15" pipe for my drainage project.