Heavy rain damages city, county roads and park
Tuesday morning rains wreaked havoc on the county’s roads and on Washington’s Sunset Park. Washington County Engineer David Patterson said there was very little rain within the city of Washington itself, and that the bulk of it fell between Washington and Kalona.
“Kalona only had a half-inch of rain, Washington had a half-inch, but the middle of the county had 3.5 inches of rain,” said Patterson. “We had to close roads north of Keota, and a few roads along the English River south of Kalona. The rain fell hard for a short time and affected a small area, so the water came and went away pretty quickly. Last week (during the flood in Wellman), water drained through our area for several days. Tuesday wasn’t quite as severe.”
Patterson surveyed county roads Tuesday and found that the early morning downpour will cost the county about $20,000 in damages to the roads and another $20,000 in damages to structures such as culverts. He said the rain pushed gravel off the road, particularly in hilly areas, and that in some places the water washed ruts down the middle of the road.
The secondary roads department is in a constant struggle to maintain gravel roads that in some cases are more than a half-century old. Patterson said that when a gravel road is laid, it is made with a crown in the middle to allow water to run off to the side and into the ditch. Over time, the crown is worn down and eventually becomes level with the ends of the road. To prevent this, road crews periodically add new gravel to the road and blade it with a grader, pushing the rocks toward the crown.
Heavy farm equipment and semis wear down the crown and push the gravel to the outside, thereby widening the road. Patterson said the lack of a crown and the expanded width of the road combine to slow the rate at which water drains from the road to the ditch. This extends the length of time the road is saturated with water, which causes it to turn soft and muddy. Patterson said heavy rains can create gullies on flat roads, which he described as analogous to having a city gutter on the road itself.
Gravel roads are 26 feet wide when they are laid, but Patterson said that in some areas of the county they have ballooned to 50 feet. He said the roads need to be narrowed and that they need a rock base 10 inches deep consisting of 5 inches of macadam stone topped by 5 inches of small rocks. Most roadbeds in the county are no more than 2 to 4 inches deep.
For more, see our August 11 print edition.