Highland Creek Stormwater Diversion
very time the southside of Indianapolis saw as little as one inch of rain, Frog Hollow, a small neighborhood of about 150 homes, would flood. Unfortunately there was no simple answer. Frog Hollow sits on low land with the White River to the west, Highland Creek to the east, and Germania Creek to the north. When heavy rains hit, the White River rises and both creeks experience backward flow.
The city asked Lochmueller Group (Lochgroup) to help find a sustainable solution. Lochgroup proposed an alternative that reduced costs significantly from initial estimates of $5 million or more to just $1.5 million. Lochgroup’s solution also avoided the relocation of existing fiber optic lines, and reduced the impact on the receiving stream by redirecting flow from Highland Creek to a nearby stormwater detention basin and a 1-acre constructed wetland. The design partially dammed Highland Creek to allow normal flow but divert stormwater to a box culvert then to a swale leading to the stormwater basin. The design redirects 75-95% of water away from the neighborhood during the majority of rain events, protecting the residential neighborhood from flooding.
The project not only reduced flooding but the wetland also filters pollutants from the runoff and provides a pleasant green space for the neighborhood.
“This fit our mission exactly. We were helping the residents of Frog Hollow, improving water quality, providing a sustainable green solution that incorporated wetlands and wildlife habitat considerations along with conserving taxpayer resources”
—Steve Nielsen, former Manager DPW’s Stormwater & Wastewater Programs