Survey
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* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Road Survey Why important: Soil erosion is the single largest pollutant (by volume) to our surface waters, and up to 85% of all erosion and sedimentation problems in lake watersheds originate from improper construction and maintenance of camp roads. Paved Roads: Generally state or town roads and not camp roads If a camp road is paved, it is a good indication that the houses along the road are year-round residences. Paved roads generally cut down on the amount of phosphorus loading because they are not comprised of loose dirt, but they still may serve as conduits for phosphorus-loading with the water carrying dust and pavement particles toward the lake Unpaved Roads: The majority of camp roads Generally made of gravel, hard packed dirt, or loose dirt A good camp road has: Proper crowning Gravel or hard dirt surface No mounds of sediment known as berms bordering the road and preventing water runoff Proper road ditching Correct placement and size of culverts Functioning water diversions Road Level Properly constructed roads are built above the natural ground. This is essential for effective surface drainage. Unfortunately, many older camp roads were built by pushing material away from the roadway, resulting in a road surface that was lower than the surrounding land. Crowning: Crowning of the road is very important because crowning serves to direct water off the road surface and into roadside ditches A good crown rises 0.5 inches for every foot of road width (a 12 ft. wide road should have a six inch crown) Indents (such as tire marks) in road are signs of erosion Ditching: Functions: o Collect road surface run-off and drain it away from the road. o Store large amounts of rainfall o With turnouts, prevent pollution from reaching sensitive water resources Ditches need to accommodate the highest possible level of storm water and seasonal runoff As a general rule, water in a ditch should never be higher than 1 foot below the top of the ditch Berms are a common problem for ditching. Winter sand and other debris gets pushed to either side of the road when it is plowed. This accumulates into long narrow piles which prevent water from getting into the ditches. Storm water runoff will eat away at the sides of the road instead of flowing off into the ditches and into a vegetated buffer. Placement: o Need to be situated along roadsides where proper crowning can direct water into them Possible Shapes: o U-Shaped o V-Shaped Best ditches: o U-shaped o Clear of debris o Lined with small stones (to slow the speed of the water) or vegetation (to absorb the water and slow it down) o Has several water diversions where flowing water can be channeled away from the lake and into a well-buffered area. Water diversions are usually at bends in the roads. V-shaped ditches are bad because the shape helps to increase the velocity of the water and increases erosion U-shaped ditch V-shaped ditch Water diversion into forested area Culverts: Used to convey water from one side of the road to the other Should be installed when: o A stream, brook, or seasonal runoff channel must be directed under the road. This keeps the road from disrupting the natural drainage system o Surface water flows reach volumes that are difficult to contain in a roadside ditch and need to be turned out on the opposite side of the road o A driveway crosses a road ditch Proper maintenance of culverts is critical to their function. Their internal frame should be complete and cleaned of debris and sediment A good culvert: o Adequate width for managing seasonal and storm-water runoff o Correct placement o Free of debris o Over a foot between the top of the culvert and the road surface Good Culvert Poor Culvert Drainage Alternatives: Water bars o A ridge (like a speed bump) that runs diagonally across the road, typically at a 30-degree angle. The ridge stops the water from running down the road and diverts it to the side o May be inappropriate for frequent (year-round) traffic Broad-based dip o Accomplishes same result as a water bar by using a shallower depression o More appropriate for year-round use but cannot be used on steep slopes Rubber bars o Can be used to divert water off sloping sections of a road o Protrudes above the ground surface high enough to intercept and collect water, while allowing traffic to pass over it o Generally used on seasonal roads or driveways because they are prone to snowplow damage Open-top culverts o Box-like structures that collect and divert road surface runoff away from the road o Prone to snowplow damage