Control on development safeguards groundwater

by Carrie Groves

SBJ Contributing Writer

Despite the unpredictable landscape beneath its feet, Springfield's continuing development is, for the most part, unhampered by groundwater problems. Federal Emergency Management Agency regulations and local building restrictions forbid construction in high-risk locations, successfully controlling flooding in newly developing areas.

The city has learned its lesson from past development problems.

Springfield sits atop limestone honeycombed with sinkholes, caverns and underground water channels. By the time the implications of building over this landscape were fully understood, the city had seen repeated and destructive flooding along most of the major creeks and at some of its larger sinkholes.

In older parts of town, wet basements and flooding are still common.Todd Wagner, a civil engineer who works for the city and specializes in water issues, said he "still hears about floodwater problems when residents call to report wet crawl spaces and basements."

Roadway flooding and pooling water in yards may also be cause for concern because the "parts of town that are extremely flat, such as the Battlefield Mall area and around Kickapoo High School, tend toward problems," Wagner said. "The groundwater table comes up quickly during heavy storms. In our shallow bedrock, water can't go anywhere very fast underground."

One solution has been to create large drainage areas for waterways like South Creek, Ward Branch and Wilson's Creek. A natural outcome of this floodplain protection is a series of streamside greenways.

FEMA guidelines specify that any new development in floodplains and around sinkholes shall be built no closer than one foot above the 100-year flood elevation, creating both a greater safety zone and permanent open space.

Sinkholes are a trickier problem. It is hard to predict how a sinkhole will fill or drain, because over time, sediment or debris can fill and alter its drainage system. The city discovered the uncertain nature of sinkholes the hard way in the early 1990s, when two major sinkholes in the south part of the city flooded so severely that 17 homes built around them had to be torn down or moved to new locations. Further development there is forbidden.

Loring Bullard, director of the Watershed Committee of the Ozarks, points out that the flood elevation in sinkholes is still, at best, an educated guess based on previous flooding, but said the regulation sets a reasonable limit for new development.

"Sinkholes are so common around here that they can't be totally avoided," Bullard said, "but by following the new guidelines established by Public Works and FEMA, we have been able to control damage."

Kent Morris, director of Planning and Zoning for Greene County, expressed a similar view. There are no areas, other than those protected by the guidelines, that can't be developed. But, Morris said, "There are a lot of sinkholes that we are aware of, and that knowledge affects how a piece of property is developed. We work with the restrictions. If someone buys a piece of property and then discovers it's a bunch of sinkholes, there's usually some frustration on the part of the owner. We work together to make the property usable. In general, the local development community understands the problems of the landscape involved."

A less easily solved groundwater issue is urban runoff. As a town covers more of its absorbent soil with concrete, less water soaks into the ground, causing more runoff. Urban runoff funneling into sinkholes pollutes groundwater that ultimately emerges as springs miles away.

Rural residential wells are now routinely sunk below the level of the water table where urban runoff emerges, but there is still the potential for long-term problems when polluted water is discharged into the surrounding water system.

Historically, Springfield has seen its share of water pollution. Railroad oil and stockyard spills have ended up in Wilson's Creek. Surface water has been contaminated by pipeline spills. Highway and railroad accidents have dumped petroleum products into local streams, and industrial products from older commercial and industrial areas of the city have tainted streams and sinkholes. Faulty sewage systems have also caused leaks and spills.

The city's groundwater future is dependent on developers' strict adherence to existing regulations. But most city and county officials agree that, if people continue to do their part, only a truly devastating act of Mother Nature can undo the progress that has been made.

[[In-content Ad]]