A big ask

Nearly $30 million would be required in Hartley to improve infrastructure and mitigate flooding problems during heavy rain events, according to an engineer's report.

The city council on Monday reviewed the final signed engineering report detailing flood mitigation infrastructure needs in town. Compiled by Bolton & Menk, it was the first part of a $100,000 Building Resilient Infrastructure and Communities (BRIC) Project Scoping grant that will cover engineering expenses related to the development of future flood mitigation strategies. The BRIC grant is administered through the Federal Emergency Management Agency (FEMA) and was originally awarded to Hartley in 2022.

The study evaluated existing storm sewer infrastructure capacity, recommended solutions and associated capital costs, and completed a cost/benefit analysis. Now that the report is on record, the city can use it as a planning document and evidence to apply for grants, cost-shares and low interest loans to complete drainage improvements that decrease flooding.

"The solutions, if constructed, will significantly reduce the flood-related challenges the City of Hartley currently faces while also reducing the amount of damage caused by all storm events," stated the report.

The recommendations included five projects within the northern watershed in town and four projects in the southern watershed. Each identified project is estimated to cost between $2 million and $5.5 million, with an overall price tag of $17 million in the north part of town and $12 million in the south.

To the north, Bolton & Menk engineers suggested converting the outlet pipe into a channel east of Second Street Northeast, upsizing the storm sewer along Second Street Northeast, and rerouting and upsizing pipe along Highway 18. Additionally, they recommended creating a detention basin north of First Avenue West and another north of Eighth Avenue West and Highway 18.

To the south, engineers suggested regrading and restoring the existing channels in the vicinity of the wastewater treatment plant. They also recommended upsizing pipes near the downtown area, creating a detention basin southwest of Neebel Park, and creating another detention basin northwest of Eighth Avenue West and Scale Road.

"This represents a significant investment in flood reduction for the City of Hartley," stated the report. "However, this does not need to be completed all at once. Individual projects can be progressively implemented over the next 30-plus years as opportunities arise and as funding allows."

Each proposed project has a benefit-cost ratio above one, meaning the benefit outweighs the cost to complete it. The projects have a combined benefit-cost ratio of between 6:1 and 8:1, depending on the expected project lifespan.

"This is especially strong within the north watershed along Second Street Northeast, where the projects have a benefit-cost ratio between 9:1 and 12:1," stated the report.

Potential funding sources like FEMA HMA, U.S. Army Corps of Engineers CAP, U.S. Army Corps of Engineers CWIFP, Iowa SRF and the establishment of drainage districts could be utilized to help pay for future improvements.

"This analysis strongly supports the eligibility for federal and state funding to help implement the recommended infrastructure improvement projects highlighted," the report stated.

Hartley officials have been discussing flooding issues for more than 10 years. When the area experiences heavy rainfall in a short amount of time, water inundates several portions of town. A particularly wet summer in 2018 led to extensive damage in Hartley homes due to flooding and sewer backups.

The city in 2022 was selected by Silver Jackets Program, which completed a survey of flooding issues in town this summer. Hartley also received a flood mitigation report in 2021 from the engineering firm Curry-Wille & Associates, of Ames.