Title
Discuss and Provide Direction on Requiring Property Owners to Remove Sediment from On-Site Ponds and Lakes
Summary
COUNCIL GOAL: Enhance the quality of Life in McKinney
(5E. Develop sustainable quality of life improvements within the City of McKinney)
MEETING DATE: August 20, 2019
DEPARTMENT: Development Services / Engineering
CONTACT: Michael Hebert, PE, Assistant Director of Engineering
RECOMMENDED CITY COUNCIL ACTION:
• Discuss and provide recommendations for possible revisions to the Code of Ordinances to address excessive sediment in ponds and lakes
ITEM SUMMARY:
• Staff is seeking council input regarding adding provisions to require property owners to remove lake/pond sediment that is considered excessive
o Excessive sediment can create significant aquatic vegetation that can be considered a negative for health and aesthetic reasons
• Some residents have expressed concerns regarding excessive sediment buildup in area ponds and lakes, potentially limiting view corridors, decreasing property values, and creating potential health and safety risks
o Health and safety risks can include
• Undesirable animal habitat
• Modifications to upstream floodplains
• Upsetting the physical/chemical/biological components of the lake
• Most pond/lake property owners have plans in place to remove sediment or otherwise mitigate the aquatic vegetation concerns
• However, some property owners have been reluctant to address sediment concerns, primarily due to cost or the lack of importance to them.
• Staff interviewed several stakeholders to receive input on proposed ordinance changes that would address the concerns
• Possible amendments to the code of ordinances could include:
o Removal of sediment when 1/3 the depth of any one acre section of the water body contains sediment
• Requirement to study the removal of sediment will be apparent due to the presence of a significant stand of cattails
• The study would then be required to determine what exists in the water body and what will be necessary to remove the sediment (allow 1 year for study completion)
• Upon completion of the study, sediment must be removed (allow 5 years to accumulate funds and complete the project)
o Install aeration in water bodies where it is determined to be beneficial by an industry professional
• Water bodies less than 6 feet of depth may not receive a benefit
• These ordinances would apply to any portion of a non-NRCS lake where the normal water surface is within 200 feet of a residential property
• Feedback from contacted stakeholders was general agreement with the distance from the lake/pond and time frames for sediment removal with the exception of those who are currently adjacent to water bodies with a significant amount of sediment. Those owners desired to see a faster completion time.
BACKGROUND INFORMATION:
• Staff has had discussions with:
o Property owners
o HOA representatives
o Developers
o Industry professionals
• Sediment removal
• Pond maintenance
• Appraisers
• Of note is industry professionals contacted were not aware of other cities that require sediment removal from amenity lakes
• Some HOA’s have had debates where some members wanted sediment removed, but others appreciated the look of the vegetated wetlands and/or did not want to pay for the removal.
FINANCIAL SUMMARY:
• Costs for sediment removal can vary greatly from approximately $20 per cubic yard to over $100 per cubic yard.
BOARD OR COMMISSION RECOMMENDATION:
• N/A