Sheetflow Erosion & Sediment Control Heavy Civil Construction

July 31, 2020

Catch Basin Covered-Infiltration

catch basin covered to allow infiltration of construction stormwater in hole cut in asphalt and filled with rock
Photo: David Jenkins

This is the first project we have cut asphalt to allow construction stormwater to infiltrate. The area is paved, flat. The sweeper runs constantly but the water is still too turbid to go down the drain. The fill soil under the asphalt is sandy. If we just covered the catch basin with 30 Mil PVC, the area would just flood, then drain to another catch basin. Solution? Cut out a section of asphalt full depth to the sandy soil, fill with 3 to 5 inch rock. This way the water infiltrates but vehicles can drive over the hole. This is working really well so we will be doing this on future container dock upgrade projects.

July 22, 2020

Covering Zinc-coated ends of the Steel Piles

Photo: David Jenkins

Need to keep the zinc out of the bay, need to cover the piles a little better.

March 30, 2020

Before and After

Photo: David Jenkins
Photo: David Jenkins

The contractor had to connect a new storm system from up the hill into an existing catch basin in the foreground. After they completed the connection but before paving, they covered the pipe run with plastic and sand bags to protect from dirty water entering the catch basin. Work was completed during dry summer weather. Paving took place a couple of months later.

September 17, 2019

Can’t Get Away From It

It doesn’t matter where I go, I always see some type of construction erosion issue. I went to visit relatives in Portland, Maine, flying in and out of Boston Logan International. In the terminal, waiting for my flight back home, I saw a construction project on the ramp; it had rained a few says before, hard. Obviously, the stockpile had not been covered before the storm and sediment washed off the pile into the drain.

I work at an airport that operates under strict turbidity effluent limits; here is how we do this kind of work:

(1) rarely do we allow stockpiles on the ramp because we rarely reuse the excavated material (it is either contaminated, unsuitable or doesn’t meet current FAA requirements); it is direct loaded into trucks and hauled off. When we do stockpile, we place dirt on plastic and cover it with plastic, using lots of sand bags to secure it from jet blast and wind.

(2) work areas are always isolated so there is no runoff from the site. Normally, we use four-inch extruded asphalt curbing along the base of the jersey barriers. Rolled hot mix asphalt (HMA) is used at the entrance point so water is contained but vehicles can access the site.  Water that builds up inside the curbing is pumped back into the excavation if clean, or a tank if contaminated.

I should have mentioned that we also have strict sediment trackout requirements: no visible sediment leaves the site at any time.  This is both because of the effluent limits and for safety reasons; dirt and debris that gets sucked up into a jet engine is damaging and possibly deadly.

Lastly, I am not casting aspersions on the folks at Logan; I don’t know their situation, permits, drainage system, or tolerance for risk.  Because of my situation, I have low risk tolerance for potential non-compliance with our permit and I notice when something would cause me grief at my airport.

October 2, 2010

Inspecting Plastic Cover

Powered by WordPress