As an addendum to our blog series on rapid, portable applications we wanted to experiment with a “thru-hull” mount of the 83/200 khz Lowrance HDS transducer on a kayak for mapping storm water retention ponds in an urban area of Minnesota (City of Maple Grove). Electrician putty (sold as “Duct Seal”) available for a few dollars at the neighborhood hardware store worked as a perfect medium for this application. Follow the series of pictures and captions to see how this worked!
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| Electrician putty or “Duct Seal” available at most hardware stores can be used for shoot “thru-hull’ applications on kayaks or canoes |
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| Figure 2. A 83/200 Lowrance skimmer transducer secured to the hull of a polyethylene kayak by duct seal putty. Care should be taken to remove all air bubbles from the mold before pressing in the transducer |
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| James Johnson from Freshwater Scientific Services LLC gets his Lowrance HDS-5 all set to log data. |
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| Tracks showing a concentric circle approach toward mapping ponds smaller than 10 acres. This one is 3 acres located in an urban area of Minnesota near Minneapolis (Maple Grove). Data took 30-min to collect |
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| Blue-scale bathymetric output created after 10-minutes of data processing time by BioBase servers after upload. Map was produced by 1,000 passively acquired GPS and bottom points. All map outputs (e.g., water volume or hardness – next picture) can be analyzed in your private BioBase online account or exported to GIS for more sophisticated data analyses and layering |
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| Bottom hardness automated output automatically created along with bathymetric and aquatic vegetation layers in BioBase. Areas that are maroon represent hard areas that remained from the original construction of the pond. Soft areas are represented by the lighter brown colors and represent sand deltas from parking lot runoff. Hardness and bathymetric outputs can be used to assess whether storm water retention ponds require maintenance and where specifically to focus efforts |