When the problem first appeared on busy Battersby Avenue, it looked like a simple pothole, maybe a couple of feet in diameter.

But when authorities peered through the hole, they found a much bigger problem. Below the surface was a gaping chasm that was, as one engineer described it, as large as a sport utility vehicle.

The bottom line was a disruption in local traffic that began April 6 and wasn’t remedied until Friday afternoon.

Battersby is crossed by Watercress Creek, a small waterway that drains water from an agricultural area south of the road and flows north. A pair of long culverts channel the water under the road.

The problem arose when one of the rusty culverts collapsed under the north side of the road, allowing the stream to wash away soil directly below the pavement.

Responsible for fixing the problem was the King County Department of Transportation and, more specifically, its Road Maintenance Division.

Early last week, crews built a temporary dam south of Battersby Avenue and, by using pumps and large hoses, diverted water around the problem area. County biologists were on hand with nets, scooping up fish and other creatures, moving them out of harm’s way.

With water temporarily out of the picture, workers slipped a new culvert inside the failed area. Once the road surface received an asphalt patch, Battersby was again open to traffic.

Jon Cassidy, a county manager with Road Maintenance, said the work completed Friday is only a temporary solution. A long-term fix could be costly and would involve the city of Enumclaw, because Battersby’s southern lane is in the city limits. Adding to the potential mix is the state’s Department of Fish and Wildlife, because the small stream is home to spawning salmon.

Reach Kevin Hanson at khanson@courierherald.com or 360-802-8205.