Rehabilitation

State of Ohio Required Action

The State of Ohio reclassified two dams as High-Hazard Class I dams requiring the dams to safely pass or store 100% of the Probable Maximum Flood. The two dams, although in good condition, have been reclassified due to downstream development and the potential for the loss of life if dam failure were to occur. The details of the alternatives for compliance are identified by NRCS in an assessment report, that can be viewed on this HCD/MCCD website.

Rehabilitation Fox Lake, Structure #6

NRCS 2009 report

In 1983 the State of Ohio reclassified Site #6, Fox Lake, as a Class I High-Hazard structure. The 2009 NRCS assessment report provided a number of alternatives to rehabilitate the dam that include:

   1.) Raise the elevation of the dam
   2.) Widen the emergency spillway
   3.) A combination of these two alternatives
   4.) Construct a roller compacted concrete (RCC) chute spillway through the dam to increase spillway capacity

Other options included:

   1.) Remove the downstream hazards and enact zoning restrictions within the breach inundation zone to prevent future development. This option is not considered viable due to the extent of development.

   2.) Remove or breach the structure to eliminate the capacity of the structure to retain floodwater. This would eliminate the potential for a breach of the structure during a storm event. Since the Operation and Maintenance agreement with NRCS has not expired, this option may require the sponsor to reimburse the Federal Government for any remaining benefits that the structure would provide over the remainder of the lifespan of the O&M agreement. This option is not considered viable due to the local reliance on the flood control benefits provided by the structure.

   3.) “No Action” alternative is not viable due to the potential for the loss of life in the downstream development.

Cost estimates for the rehabilitation alternatives at site #6 range from $1 million to $4 million depending on the option selected. No cost estimate was provided by NRCS for dam breach or to remove downstream hazards.

Enviromental Assessment and Watershed Supplemental

Plan 2020 Fox Lake 

An Environmental Assessment and Watershed Supplemental Plan was started in 2020 by NRCS with the assisstance of a third party and MCCD to determine the best alternatives available to rehabilitate Fox Lake dam. This is a very extensive study and as of 2022 still not approved. The options available include.

   1.) Decommissioning the dam.

         
         Decommissioning the dam would require the excavation of the embanment and restore the stream channel, remove and dispose the excavated soil from the dam and spillway. The conceptual cost estimate in 2021 to decommission the dam was $3,075,000.00.   

   2.) Structural rehabilitation with approved earth to elevate the dam crest.  

         Structural rehabilitation requires the dam to be elevated with approved earth, replacement of the toe drains, and line the auxillary spillway with articulated blocks. The use of a parapet wall is not feasible in this situation. The conceptual cost estimate to rehab the dam under this option would be $2,652,200.00.

   3.) A future without federal investment. 

         Afuture without federal investment means MCCD would not be eligible for federal funding to rehabilitate the dam and NRCS would no longer be involved with the project. However, we would still need to compy with State of Ohio regulations requiring MCCD to line the auxillary spillway with articulated blocks, install a training dike, and replace the toe drains. The conceptual cost estimate is $2,083,700.00 of which we would receive zero federal funding. 

These estimates were calculated on 2022 costs and may need to be adjusted once the option to rehabilitate the dam is determined.

Rehabilitation #1, Meeks Lake

Meeks Lake dam built in 1972 was originally designed as a “significant” hazard structure. It protected agricultural floodplain and had a county road about 0.6 miles downstream and two other railroad crossings within another 0.8 miles. No loss of life was envisioned if the dam were to fail. In 1990 the Ohio Department of Natural Resources reclassified Site #1, Meeks Lake, to a Class I High-Hazard structure. The 2010 NRCS assessment report provided a number of alternatives to rehabilitate the dam and are described below.

   1.) Decommissioning the dam.

         Decommissioning the dam would require the excavation of the embankment and restore the stream channel, remove and dispose of the excavated soil from the dam and the spillway. The conceptual cost estimate in 2021 to decommission the dam was $1,586,300.00.

   2.) Structural rehabilitation to raise the crest of the dam with the use of approved earth.

         Structural rehabilitation requires the dam to be elevated with approved earth, the replacement of the toe drains, and line the auxillary spillway with articulated blocks. The use of a parapet wall is not feasible in this situation. The conceptual cost estimate to rehab the dam under this option would be $3,488,000.00.

   3.) A future without federal investment.

         A future without federal investment means MCCD would not be eligible for federal funding to rehabilitate the dam and NCRS would no longer be involved with the project. However, we would still need to comply with Sate of Ohio regulations meaning we would have to line the auxillary spillway with articulated blocks and replace the toe drains. The conceptual cost estimate is $2,691,000.00 of which we would receive zero federal funding to rehab the site.  
        

Jim Rozelle with Storm Water Engineering a consultant for MCCD that estimated the cost of paying back the Federal Government and removing the two dams to be $350,000 more than the 20-year Maintenance Assessment. This is without factoring in the continued maintenance of the other two dams. In addition, the recreation benefits at Fox Lake would be diminished, as well as the loss of flood protection for structures, agricultural land and transportation facilities.

Structure #6 and #1 are eligible for assistance authorized under the Rehabilitation Provisions (PL 106-472) of the Small Watershed Program (PL-566), administered by NRCS. Funding for rehabilitation is based upon a priority ranking system, which considers the potential for dam failure and the potential consequences of dam failure. High hazard structures are given a higher ranking for funding than low hazard structures. The rehabilitation provisions of PL 106-472 can provide 65% of the total cost, but shall not exceed 100% of the actual construction costs incurred in the rehabilitation. The 65% Federal cost share would provide the majority of funds necessary for the rehabilitation of these two dams which reduces the local share to 35%. This 65% is a valuable source of funds that we cannot afford to lose if the Federal governement chooses to eliminate this program.

Rehabilitation NRCS 2010 Assessment Report Meeks Lake 

1.) Modify the dam and auxillary spillway to safely pass or contain the larger runoff from the probable maximum precipitation as required for design of a high harzard structure.

     a.) Raise the elevation of the dam with earth fill and widen the emergency spillway.

     b.) A parapet wall to raise the elevation of the dam and widening the emergency spillway. 

     c.) Construct a roller compacted concrete (RCC) chute spillway through the dam to increase spillway capacity.

     d.) Widen the auxillary spillway and adding a RCC spillway in the existing embankment.

     e.) "No action" alternative is not viable due to the potential for the loss of life in the downstream development.

2.) Ensure that appurtenant structures (riser, internal drains, etc.) meet curren NRCS and State Dam Safety criteria.

3.) Ensure that the sediment pool has a minimum sediment storage capacity that matches the rehabilitation evaluation life period.

Potential rehabilitation alternatives prove to be more limited due to a home on the right abutment of the emergency spillway and a county road on the left of the dam, which precludes adding a second auxillary spillway in the left adbutment. Raising the top-of-dam flood pool increases the depth of flooding on the two homes already in the existing top-of-dam flood pool and possibly brings two additional homes within the flood pool. It also increases the potential depth of flooding on two county roads and on state highway in the upstream flood pool.

The rehabilitation cost estimates range from $500,000 to $1.3 million. The cost for elevating the state highway (SR 681) was not included in the cost estimate. The least costly and detrimental rehabilitation will be the RCC chute at a cost of $770,000 to $890,000.

The costs for both Structure #1 and #6 are preliminary estimates only.

The combined estimated cost to rehabilitate Site #6 and #1 to pass 100% of the Probable Maximium Flood as required by the State of Ohio, is between $1.8 and $2.1 million. The local share o 35% could exceed $750,000.

Environmental Assessment and Watershed Supplemental Plan 2020 for Meeks Lake 

NRCS committed a great deal of time and money for a more detailed study called an Environmental Assessment and Watershed Supplemental Plan of these structures in 2020. This study will define the entire scope of the rehabilitation needs to bring them both into compliance with federal and state regulators.

An Environmental Assessment and Watershed Supplemental Plan was started in 2020 by NRCS with the assisstance of a third party and MCCD. This extensive study revealed the following options available. 

Before NRCS commits a great deal of time and money for a more detailed environmental study of these structures, assurance is required that the Subdistrict is committed to the rehabilitation of these two dams and can secure the funds necessary for the 35% local share. This study will define the entire scope of the rehabilitation needs.

Environmental Assessment 

Margaret Creek Conservancy District & NRCS welcome public comment for Margaret Creek Watershed Structures 1 & 6 (aka Meeks Lake & Fox Lake) for Enviromental Assessment.

1st meeting September 2, 2020 via 

https://parecorp.zoom.us/my/margaret.creek

2nd meeting April 8, 2021. To view the presentation and alternative evaluations visit: 

https://margaretcreekstructures1and6.ucraft.site/

Send questions of upcoming Environmental Assessments to MargaretCreek@parecorp.com