Riversidean
Your situation suggests the hinge is to close to the shoulder and your last sentence suggests this would be a temporary setup. If so you may consider sacrificing shoulder width to set temporary (mechanically linked) concrete barrier backed by earth/gravel fill. A real solution is...
IRstuff
Thanks for the chuckles. Tomorrow can not come soon enough for me to discuss this fruit/vegetable subject with my fellow engineers at the orifice. Highway and drainage engineers have the best sense of humor.
