Levee Options for Maximum Benefit

by Bill Beranek

Midtown neighborhoods have good options in front of them to lift property owners completely out of the 100-year flood plain as quickly as possible, to save the Central Canal, and to help as many neighbors as possible while hurting as few as possible.

Broad Ripple and Warfleigh neighborhoods now have a reduced flood risk due to a 300-year flood wall from above the Broad Ripple dam downstream to the Riviera Club. The reduction in risk is substantial for higher-elevation properties and less for the lower ones.

A 2013 study undertaken at the City’s expense identified some areas of Warfleigh and Broad Ripple that are protected by the current flood wall. The City has approached the Federal Emergency Management Administration (FEMA) about obtaining conditional certification under a program called Levee Analysis and Mapping Procedure (LAMP).

To remove properties protected by the existing levee from FEMA’s 100-year flood plain designation, the City must first undertake vegetation removal in Warfleigh and Broad Ripple. According to Mike Massonne, a Department of Public Works (DPW) project manager, the U.S. Army Corps of Engineers (USACE) insists on the vegetation removal. “LAMP is hinged on the permit [for vegetation removal],” he said. “The Corps has stated that if trees aren’t removed, they won’t certify.” Without certification, Massonne said, the City cannot proceed with the LAMP process.

To move forward, the City applied to the Indiana Department of Natural Resources (DNR) in September 2014 for a vegetation removal permit. Any modification to river banks requires DNR approval. To comply with the terms of the permitting process, DNR hosted a public hearing in December 2014. Citizen complaints about lack of sufficient notification led DNR to host another hearing in March to solicit public testimony about the proposed vegetation management area.

At the hearings, members of the public pointed out that DNR has an obligation to protect wildlife habitat and that this stretch of the White River corridor supports a diverse wildlife population, including bald eagles, Indiana bats, and assorted mammals and rodents. While not addressed by current statute, climate change and aesthetics were also considerations. Residents testified that they live in the area because of the dense tree canopy, which not only provides visual relief but also absorbs carbon dioxide. The dense vegetation also provides erosion control, according to testimony.

On June 11, DNR sided with the petitioners and issued a certificate of approval for construction in a floodway. The permit may be appealed by applying for administrative review within 18 days of the notification (June 29). It is highly likely an appeal will be filed.

In the meantime, work is proceeding on the southern section of the levee project, which currently terminates at the Riviera Club tennis courts. DPW has allocated funds for right-of-way acquisition. According to DPW’s Massonne, the City’s project agreement with the USACE makes DPW responsible for obtaining easements and conducting outreach meetings. “Currently, DPW has right-of-way acquisition contractors looking at the easement for a levee across the Riviera Club property that would extend south to a point that would not preclude any other consideration brought up for Rocky Ripple for a west Canal bank or Westfield Boulevard alignment.” He said the City hopes to engage the Riviera Club in discussions by the end of summer.

Regardless of the route south of the Riviera Club, it will likely take several years to plug the gap across the Riviera Club property. The City needs to obtain the property, determine the route (whether to go along the riverbank or inland around the club property), and to construct the segment.

By the time the Riviera Club section is addressed, alternatives to the USACE’s preferred alternative along Westfield Boulevard would be at the same state of approval for final execution as the West Bank option.

South of the Riviera Club, there are three potential options to allow FEMA to formally remove all neighborhoods east of Rocky Ripple from the 100-year flood plain for insurance purposes as long as the barrier is maintained.

The Westfield Boulevard Flood Wall Option

CLICK TO ENLARGE. A range of options for consideration. Adapted from DPW map.

The choice of the Corps of Engineers is a 300-year flood wall extending over the Canal at Capitol Avenue and south between Westfield Boulevard and the east bank of the Canal to Holcomb Gardens at Butler. The City has refused to participate in that project and the USACE must have agreement from the City to proceed. The City refused to support this option primarily because it does not protect the public drinking water supply. Additionally, neighborhoods were concerned that it splits the recreational towpath along the Canal, isolates Rocky Ripple with sand bag barriers prior to a big flood, and would require reinforcement of the west bank to prevent flooding from the Canal into Rocky Ripple if a flood wall were constructed along the river to protect the Rocky Ripple flood plain.

The Canal West Bank Option

The City has contracted with an engineering firm to study the feasibility of using the reinforced west bank of the Canal to complete the project. The reinforcement is almost entirely underground. This route would protect the water supply, would not require a flood gate and wall across the Canal, would not require sand bag barriers at 52nd and 53rd streets to protect Rocky Ripple during a flood event, and would not affect Holcomb Gardens.

This option does not protect the Butler University/Rocky Ripple flood plain from flooding but it is a step toward that protection, unlike the Westfield Wall that could actually enhance flooding there under certain circumstances. The West Bank option does require sophisticated engineering to minimize the impacts on several Rocky Ripple property owners along the Canal.

This option could be constructed to the USACE’s 300-year flood design standard or to the less expensive but still adequate FEMA 100-year flood design standard.

The City’s rigorous technical feasibility study, an effort the USACE did not undertake when it originally discounted this option, is scheduled to be completed by early autumn. If the USACE agrees with the technical feasibility study results and if the option would be less expensive than the Westfield Boulevard Flood Wall segment for greater risk reduction, the USACE could accept it as its preferred option with a new Record of Decision. That would require a new public hearing with a modestly revised Environmental Impact Statement. That process could be completed within two years. A decision to shift from the Westfield option as the final segment could be completed prior to start of construction of the Riviera Club segment.

The Butler University/Rocky Ripple Flood Risk Reduction Option

The original USACE proposal in 1996 was for the Town of Rocky Ripple to be encircled along with all the upriver neighborhoods by a flood barrier. In the 2013 Environmental Impact Statement, the USACE included an estimate for a single option using a 300-year flood standard circling the town. It said that its cost estimates exceeded the value of the property being protected and therefore it could not justify participation in that project.

A third option now would be to change the proposed enclosure to encircle both Rocky Ripple and a good portion of the Butler University property. This would require a reinforcement of the Canal berm at the 56th Street bend of the river between Capitol Avenue and high ground close to 54th Street. With that, the Canal would be protected from washout, and potential back-door flooding from the Canal into Rocky Ripple would be closed off. This could all be constructed to the FEMA 100-year flood standard instead of the USACE’s 300-year design used in upstream portions of the project.

Going around the Rocky Ripple flood plain would allow FEMA to remove neighborhoods from Broad Ripple through Rocky Ripple from 100-year flood plain without constructing either the West Bank or Westfield Boulevard Flood Wall options.

Two strategies to consider for the Rocky Ripple flood plain are:

  1. Undertake a more rigorous technical and economic feasibility study using the FEMA 100-year design standard and adding the Butler property, and request that the USACE reconsider its decision (for engineering reasons it could be significantly less than the USACE 2013 cost estimate). If the engineering study began immediately, the time frame for a USACE decision would be similar to that of the West Bank Option, and thus would not slow down the overall project completion schedule.
  2. If the USACE refuses to fund construction but approves the technical feasibility of the new design for flood risk reduction, assemble a coalition with a special conservancy district or other such local government mechanism to collect local commitment for the cost of the segment. That also could be accomplished in the same time frame so that the overall project completion would not be delayed.

Several factors now converge to determine when this project might be completed. A new City administration starts January 2016 and needs time to be brought up to speed in order to formulate its policy on how to fund the City’s share of the project. The continued unpredictable timing and availability of federal funds is a key factor because the USACE could pay for the majority of the flood barrier construction.

For FEMA to consider removing affected properties out of the 100-year flood plain, the USACE needs to certify the completed barrier. This requires removal of trees in Warfleigh and Broad Ripple (or the USACE to change its mind) and mitigation for forested wetlands destroyed as well as design and construction of the southern segment of the flood project. If all goes well, the total project completion time will likely be on order of 10 years regardless of option.

That time frame should not discourage neighbors, City officials and affected institutions from working together now to assure that the completed project benefits as many people as possible at a reasonable cost and with minimal harm to the greatest number of people.

Bill Beranek, an environmental mediator with a Ph.D. in chemistry, is a longtime northside resident. He has been actively engaged in analyses and discussions with all key government agencies and affected parties for three years to help find a reasonable solution to managing White River flooding. Additional reporting by Thomas P. Healy.

A version of this article appeared in the June/July 2015 issue of the magazine.