BajaOR, post: 347022, member: 9139 wrote: I took him to mean "feeling around" not with hands but with with a designated "stinky rod", used only for that purpose.
I've got to tell this story:
One of past employers utilized Chevy Suburbans for field vehicles. Most of the crews at that time had 4 butts. Hence, all the "long" gear was stowed in PVC tubes on top of the 'burban. Depending on the terrain, it could be a tippy-toe affair to reach up to the tubes.
Well...it happened. The "stinky rod" still had some residual "influent" in the bottom of the fiberglass level rod. When one of the guys tipped it up to shove it home in the tube on top of the truck, he was looking up his nose....with his mouth open...:-O
After we got him to stop dry heaving I had to convince him he really didn't need to go to the ER...AND in a technical sense, most sewage influent is really 99.5% water with a few suspended solids....
He didn't buy it. He thought he was dying for the next six months.
Iceman, post: 346980, member: 579 wrote: We have even used a scanner to scan the inside of a manhole.
Please tell me more, how well did this work out for you?
We typically don't pull grates such as the one shown. I would measure down for invert elevation if the pipes are visible.
In this case I would probably note the rim elevation and that the structure is full of water or debris. I wouldn't want my
crew feeling around and assuming pipe sizes and invert elevations.
I open them up and measure down if at all possible. This gives me the advantage of estimating the center of the structure and in some cases the direction to the next structure. However, if there is a bag in the CB, the type for temporary sediment control, I never pull the grate. Did that once and spent the next hour fishing it out of the bottom.
I require my crews to open every manhole they shoot along with all grates and cleanouts.
If the lid is bolted, locked, or otherwise rusted shut, I'll let them pass on opening it. But typically I'll contact the local agency (city/county) and let them know that we're surveying and would like to get invert information.
They are supposed to have a dedicated "poop rod" for measuring down to inverts. A flashlight and such is always helpful to get accurate pipe diameters as well. And my crew knows to take the proper precautions if they are opening any non-round grate to ensure it doesn't fall in. I've fished out exactly 2 in my life. The first was my fault (and was fortunately only 4' down). The second wasn't my fault, but the guy I was working with had seniority and so I fished that one out (about 6 feet down).
I figure that if I can go out and get inverts on a sanitary sewer manhole that is 20 feet deep, then the crews in the field, that are about 20 years younger than me, can do the same.
I've backed off from using too much force in smacking the lids with a sledge hammer. No lie, I had one break on me after hitting it with an 8 pound sledge. It must have had a hairline crack or something, because it split out a pie-shaped wedge that dropped into the manhole and the rest of the lid split and it hung wedged in the rim of the lid frame. I was shocked. And so was the City Public Works guy that came over to put a new lid on it! He called me The Hulk for at least 2 weeks after that.
Some municipalities will not allow you to pop the lids. Colorado Springs for example has designated people to get or provide the invert measure downs, sometimes the information is not as accurate as might be needed, but it is what it is.
About 20 years ago when I worked for a local city I pulled a big curb inlet grate. It got a little sideways and dropped down in the inlet box and almost took me with it. The box was full of water so I called the Public Works Vactor truck, they sucked the water out and pulled the grate back out. Got a good invert and flowline out after the water was out.
A couple of years ago I was doing monitoring wells at a fire station in Leggett. The stupid things had 12" round boxes with an iron lid that screws in and we didn't have the special tool to unscrew them. It's a real bear to unscrew a 12" lid with a little grit in it with two pieces of rebar. There was one behind the building that we couldn't budge without rotating the whole box because it wasn't constrained by parking lot pavement like the others. A muscular 20 year old 6-8 fire fighter said I'll get it open. He swung my 10lb sledge over his head and shattered the lid into several pizza pie pieces. It was open. They sealed them with concrete soon after so the missing lid wasn't as big a problem as it would be in the street.
I used to do a lot of town wide sewer mapping and Infiltration and Inflow inspections and I have broken quite a few manhole lids too. I worked robotic one man crew from the beginning of my career doing mostly engineering topo. It'snot fun crawling into a catch basin to fish out a grate in a high traffic area by yourself. I always wondered what the folks driven by thought when they saw a head rising out of the catch basin.
"...it split out a pie-shaped wedge that dropped into the manhole and the rest of the lid split and it hung wedged in the rim of the lid frame."
This is exactly why it baffles me that any agency would allow any Tom. Dick or Harry to come along and break into their facilities and leave who knows what behind. Makes little if any sense... They need to learn to be responsible for their faclilties themselves.
I have measured hundreds of inverts in my career, but have never, and will never, enter a manhole, inlet, or confined space. I am not trained to enter such space.
I have a Pipe-Mic for getting inverts. I have also used a digital carpenters level and 25' rod before I got the Pipe Mic. If a structure is full of water, I note it on my plan, and let the client arrange to get the structure cleaned out.
So, what's the deepest manhole you've ever encountered?
27ft or so.
[SARCASM]That's what "he" said.[/SARCASM]
Ron Lang, post: 346915, member: 6445 wrote: I'm not asking them to go into the structures, only open them to get a good view of whats going on down there. With the design of the these particular grate tops, it is extremely difficult to a view of the inverts. Not to metion the fact that they are full of water. I agree in that I'm not cleaning them, but I don't think taking the lid off is feeling around the sides for pipes is asking too much of a crew now days. And certainly if the information can be gathered without removing the top I'm fine with that. In fact I find that the issue only comes up when there is a problem and they can't determine whats going on down there from the topside.
If your employee could fall into the opening it will be considered a confined space, even if you do not intend to enter it.
foggyidea, post: 346870, member: 155 wrote: I think that they just need to be shown how one time. Add a shovel to the tools and you should be all set for most manholes.
I'm not sure what sort of information you would expect from the grate shown in the photo. If I was doing it I would note, on the plan, that the catch basin was full and inverts were not available.
Dtp
Which what I intially did, however engineer not happy with that and asked for more info. I thought if we could open the lid and feel around the sides and bottom with a level rod we might be able to give hime better info. But getting the top off seems to be the issue. Like I initially it was standard practice to remove lids back in my early days. With the tools we had and mus
BajaOR, post: 347022, member: 9139 wrote: I took him to mean "feeling around" not with hands but with with a designated "stinky rod", used only for that purpose.
Yeah i meant with a rod not there hands, lol. Come on guys. Lol
Just over 20' or so. Which is good because I always used a 25' fiberglass rod to measure inverts.
I think the worst part about all of this is opening the sanitary sewer manholes. And I've opened up some very, very, VERY "unpleasant" ones in my travels.
I've also had the misfortune of accidentally dropping things into them including flashlights, pencils, a small camera case (the camera was safely strapped to my wrist), and a clip board (with notes of the previous few manholes that had to be re-measured).
I don't advise my crews to open a manhole in the street unless they have a second crew-person to watch for traffic.
I once had the bottom section of a 25ft ROD with a pipe mic on it come off and sink to the bottom of a 30ft deep wet well which was about half full. Duct tape, and a manhole pic makes a nice fishin pole. It took me about an hour but I finally got it out.
Heh, when I accidentally kicked the camera case into a manhole, it was only about 7 feet deep. It was a terminating manhole, so it had virtually no flow (other than the two residential laterals that fed into it). The case landed high and dry on the side of the barrel. I tried for about 20 minutes to fish it out with various implements that I had in my work truck, but to no avail. I left it there for future investigators to find and speculate as to why it was down there.