Utilizing Bathymetry to Budget for Future Repairs and Dredging

Written by Industry Expert, Kevin Tucker, Chief Executive Officer

If you live in a planned community governed by a Homeowners’ Association (HOA), are part of a lake association, own commercial developments, belong to a golf club, are a member of a recreational club, or you are a board member or manager for any of the above, you are likely familiar with the need to maintain a reserve and replacement budget. In many cases, it is a statutory requirement.

Reserve Studies are a great tool to help prepare stakeholders for significant future repair and replacement expenses. They often uncover items that might not have been top of mind if left unaddressed, but would pose a significant financial risk to the group. In most cases, the Reserve Specialist preparing the report is able to identify very accurate estimates for the expected life of your physical assets, as well as the corresponding costs for making significant repairs or replacing them as their expected life comes to an end.

As valuable as these studies can be for those whose responsibilities include managing a lake or pond, we find that they are typically missing one key piece of information…Dredging! In many cases, dredging will be the single largest expenditure a community or development will ever face and we want you to be prepared.

Most planned communities, commercial developments and golf courses have stormwater lakes or ponds incorporated into their overall development designs. These stormwater management facilities are designed to collect all stormwater flowing in from the community’s impervious surfaces such as roofs, sidewalks, and streets. In doing so, all of the sediment, grass clippings, leaves, fertilizer, other organic matter, and pollutants contained in this stormwater will be collected and settle to the bottom of the pond.

This is good news for our streams, rivers, bays, and oceans, as these lakes and ponds filter runoff water and help ensure that only clean water is discharged into our natural waterways. However, it creates what could ultimately be a costly maintenance headache. What do you do when your lake or pond has enough accumulated sediment and organic matter that it needs to be dredged in order to continue to function properly?

Although Reserve Studies do typically address the potential need for dredging, they are not necessarily accurate or specific to your particular site. Every waterbody is unique, and the demands put on each system will vary based on the size of the overall watershed, weather conditions, landscaping and fertilization practices, and level of ongoing annual lake and pond management activities.

If you want to accurately evaluate the current sediment accumulation in your lake or pond, and project forward to when it will need to be dredged, and how much it will cost to do so, there is only one choice…bathymetry.

Bathymetry is the process whereby the surface of the lake or pond is plotted using GPS lake mapping technology, and each of the GPS points recorded is correlated to the corresponding depth of the waterbody at that specific point. After collecting thousands of surface points with their associated depths, a three dimensional model of the bottom of the lake can be developed. With this information, the current maximum storage capacity (volume) of the waterbody can be quantified and compared to original design plans to determine how much of the original storage capacity has been displaced by the accumulation of sediment and organic matter. We can then determine the anticipated cost to dredge, or if dredging is not needed now, project forward to when it will be needed based on the sedimentation rate calculated from the information gathered.

All lakes and ponds will need to be dredged at some point… are you prepared?

Contact the experts at 888-480-5253 for all of your lake, pond and fisheries management needs. 

Kevin Tucker started SOLitude Lake Management to focus on the growing need for adequate management of lakes and stormwater retention ponds and the preservation of our natural resources.  He is an active member of many leading trade and professional organizations and remains on the cutting edge of technology, product, and service improvements in the aquatics industry.  Kevin has been a speaker at many trade and professional shows and conferences, and is a regularly published author for many industry related publications. Kevin is widely recognized as an expert in the management of lakes, ponds, and other freshwater systems, as well as the management of invasive aquatic plants. 

SOLitude Lake Management is committed to providing full service lake and pond management services that improve water quality, preserve natural resources, and reduce our environmental footprint. Lake, pond and fisheries management services, consulting, and aquatic products are available nationwide. Learn more about SOLitude Lake Management and purchase products at www.solitudelakemanagement.com.