Roadside Plastic Barrier Errosion Control?????

[OkeeDon]

But, look at what the city's utility department did, right outside the silt fences! This hole, and the one in the next post, are to bury a water line under the street. They dug them over a week ago, and then just left them.

 

[OkeeDon]

This is the matching hole across the street.

My driveway is just down to the left.

There is another construction site a few hundred feet up the road I wanted to get, because the building is nearly complete, and the silt fences are in complete disarray, falling down, and with dirt over them. But, the rain started falling a little harder, and made my bladder active, so I quit.

 

[OkeeDon]

Interestingly, it had been raining -- very hard -- for about 4 hours before I took these pictures, and there was not one ounce of silt or washout. These things may have value where there are slopes, but here, where it''s flat, they appear to just be a waste of the developer's money. We have had over 41,000 homes and commercial buildings constructed within the city in the last 30 years before these regulations came into effect, and I can't remember ever seeing any silt or clogging in the swales that wasn't caused by machinery driving through them.

 

[jinman]

I always referred to these fences as <font color="red"> dust </font> fences. I thought they were designed to stop most (80%?) of the blowing dirt/dust that is concentrated about 18" from the ground. I haven't seen any of them that are very effective for stopping flowing water-borne silt of any kind.

 

[keeney]

To be effective at controlling the water-borne silt, the fence has to cause the flow to slow down or stop. If the water ponds up behind the fence, the slit will settle out and not be carried along with the water.

Normally, there needs to be an over-flow in case the water flow is unusually high, and a slower seeping or leakage action to drain it down after it stops raining.

 

[Currmudgeon]

</font><font color="blue" class="small">( It is part of the building code in most municipalities. I think it might be in the model codes they all adopt. )</font>

Erosion control is also part of of the Federal water pollution control measures required in every state. Until last year, sites that disturb more than 5 acres needed an Erosion Control Plan. Now it's one acre. Many municipalities require it on all sites.

I like the stuff because it does a good job of defining the limits of disturbance, keeping the Contractor from extending his devastation into inappropriate ares. That's why you sometimes see it running along the uphill side of the site, where it does no good.

It doesn't work too badly, provided you maintain it, fix the holes, and don't let stuff back up behind the fence too high. The Contractor really needs to walk the fence every few days and after every rainstorm.

</font><font color="blue" class="small">( They do work. Down by the lake after a big storm, the silt fence was over-flowing. It was about 18" to 24" high. The stakes barely held the water. )</font>

That's a bad applicatioon for one. They tend to wash out when they back up that much, and you get stuck with a whopping fine. For areas where water is expected to pass, I'd rather put in a gravel check dam, to filter the water. That will stand a lot more load before it fails.

</font><font color="blue" class="small">( Later when the water drained down, I discovered that there was about 18" of silt that had collected behind the whole area of the fence. It took half a day of digging with my little 4100 to "empty" the silt fence just in time for it to start raining again.)</font>

Our standard spec calls for the silt to be removed, like you did, when it's half way up the fence. That can be a helluva lot of dirt.

</font><font color="blue" class="small">( The contractors who knew about silt fences because they have to deal with putting them up and maintaining them themselves were careful not to destroy the fences. Those who didn't know or care, seemed to delight in running over it with trucks, cranes, and Bobcats. )</font>

That just indicates a sloppy super. Once the silt cops write him up and he has to explain to his boss that his construction budget is now $40K slimmer, he usually gets religion.


</font><font color="blue" class="small">( Could be a nice business opportunity for somebody with a CUT and one of those attachments going around on bigger construction sites. )</font>

In the process, be able to take care of the other erosion control features, like catch basin dirt bags, gravel checks, and the rest. There may be money in it if you can market it. But you'll need to figure out how to manage the liability. One release and you could be liable for a lot of dirt.

 

[EddieWalker]

"I haven't seen any of them that are very effective for stopping flowing water-borne silt of any kind. "

I catch so much silt with my silt fences that I must clean them out after every big rain.

My soil is red clay. It packs hard as a rock, but after working it a little, it will take some time to pack down again. During this time when it rains, I can end up with 4 to six inches of silt build up along my fences.

 

[RonR]

I sure appreciate the inputs posted here. I've just started a part time business and plan to do rototilling and some FEL work. I won't be doing new construction sites, etc, but am now worried enough that I plan to do some reading about silt fences and maybe talk with our city engineer to see what I need to do/not do.

THANKS.

Ron

 

[Currmudgeon]

Your State EPA may have a manual on Erosion Control. Hopefully, it's even available on-line. In Illinois, it's the Illinois Urban Manual. These include a number of techniques, called Best Management Practices (BMPs) (e.g silt fence) that can be used to limit erosion.

A roll of silt fence and a roll of that orange mesh construction fence may be cheap insurance to carry in the back of your truck.

 

[RonR]

Thanks. I have looked a little online and found some information about them. I'm sure they aren't that expensive. But you'd need to know the why's and wherefore's to installing them.

The problem I'd have is WHERE to put them, or if I needed to. I'd look pretty silly setting one up just to rototill a garden, for example!

Thanks.
Ron

 

[keeney]

<font color="red"> That's a bad applicatioon for one. They tend to wash out when they back up that much, and you get stuck with a whopping fine. For areas where water is expected to pass, I'd rather put in a gravel check dam, to filter the water. That will stand a lot more load before it fails.
</font>

What I learned and applied when I eventually replaced that fence was that the fence belongs further down on the flat area of the downhill, not on the very toe of the hill. That leaves a lot more area to collect water before it backs up high enough to overflow or destroy the fence.

A gravel dam would have cost a lot more money. The fence was only about $50 in materials. Hauling in enough gravel would have been maybe $500.

( The contractors who knew about silt fences because they have to deal with putting them up and maintaining them themselves were careful not to destroy the fences. Those who didn't know or care, seemed to delight in running over it with trucks, cranes, and Bobcats. )

<font color="red"> That just indicates a sloppy super. Once the silt cops write him up and he has to explain to his boss that his construction budget is now $40K slimmer, he usually gets religion.
</font>

Unfortunately, we were self-contracting our own house, so it was my problem to deal with if there was a fine. Yes, I complained to the contractors who did the damage, and some of them even made half-hearted attempts to repair the fence. I held back $100 from one sub who didn't bother to come back and fix what they destroyed, but I didn't have a lot of leverage over supplier and freight company delivery trucks where there was no money to hold back.

So, I was the one personally out in the mud and dirt with a shovel, hammer, and staple-gun replacing and repairing the damaged sections.

That summer was one of the rainiest we have had around here in a long time, so runoff control was tested to its limit, but no significant amount of mud made it into the lake that I am aware of.

- Rick

 

[rambler]

The tree-huggers have required it in most all locations. So we get a lot of extra thrown-away plastic in the landfills (or it sits there looking ugly forever), and in 90% of the construction projects I see, it's totally pointless. Guess we can't have any laws that make sense - just cost money.

For example, here in Minnesota it was found that gravel is an enviornmental hazard, so now they put a lot of salt on the roads with very little gravel. Roads are _very_ slippery now with no gravel to anchor down on the roads, just a sheet of ice with melted salt water on the top. But I guess everyone is happy. Salt is fine, gravel is bad for the environment. Guess I'm just too dumb to understand.

--->Paul

 

[Currmudgeon]

</font><font color="blue" class="small">( A gravel dam would have cost a lot more money. The fence was only about $50 in materials. Hauling in enough gravel would have been maybe $500. )</font>

That's the sort of argument that justifies the $10,000 fine for releasing sediment. A silt fence is not an acceptable solution for filtering silt from a watercourse. They're generally not strong enough. You dodged a bullet on that one.

</font><font color="blue" class="small">( Unfortunately, we were self-contracting our own house, so it was my problem to deal with if there was a fine.)</font>

That's a major problem with self contracting. The subs all know thay'll never work for you again, so they think they can crap all over you. Every other job is more important. It can make juggling subs a nightmare.

In that situation, the best you can do is to sweat bullets and remember how much money you're saving by not paying a General.

</font><font color="blue" class="small">( That summer was one of the rainiest we have had around here in a long time, so runoff control was tested to its limit, but no significant amount of mud made it into the lake that I am aware of. )</font>

And that's the final test - the one every Contractor relies on. "It worked." Can't hardly argue with that. /forums/images/graemlins/cool.gif

 

[Currmudgeon]

</font><font color="blue" class="small">( in 90% of the construction projects I see, it's totally pointless.)</font>

This is generally a problem, wither with a dumb contractor, who doesn't know where to put it, or a dumb inspector who doesn't know where it's needed. Actually, there's a third reason - fear of lawyers. Silt fence is cheaper than lawyers.

The only place you actually need the stuff, according to every state where I've done projects, is where it can actually intercept silt.

</font><font color="blue" class="small">( here in Minnesota it was found that gravel is an enviornmental hazard, so now they put a lot of salt on the roads with very little gravel. )</font>

I thought it was the salt that caused theenvironmental hazard. <shrug> I guess we're all supposed to ride horses. Now THAT will make the roads nice and clean.

 

[Chechnya]

On the project im building, i was required to place silt fencing alot the bottom of two rention ponds i have and along side the whole street side. Luckily i was able to plant grass and got rid of the silt fencing. 100 foot with wood stakes is about 30 dollars.

 

[Chechnya]

For the people questioning the effectiveness of silt fencing, i have to question your experience with it. It does a fantastic job of what its supposed to be used for if installed correctly.