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City of Miami Beach, 1700 Convention Center Drive, Miami Beach, Florida 33139, www.miamibeachfl.gov
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| | | | | | | | | | Item 2.
COMMITTEE MEMORANDUM | | | |
| | | | | | | | TO: Land Use and Sustainability Committee
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| FROM: Alina T. Hudak, City Manager
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| DATE: July 12, 2021
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| | | | | | | | | TITLE: | DISCUSS LITTER GETTING INTO THE CITY'S STORMWATER DRAINS WITH POTENTIAL ACTION IF DEEMED NECESSARY. |
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| | | | | | | | HISTORY:
| At its March 17, 2021 meeting, the City Commission approved a referral to the Land Use and Sustainability Committee (LUSC) to discuss litter getting into the City's stormwater drains with potential action if deemed necessary.
The referral originates from a Biscayne Bay Health seminar that took place on February 19, 2021. During this seminar, discussions identifying the need for Miami-Dade County and the cities of Aventura, Miami, and Miami Beach to take on a new set of goals were had, including the benefit of coordinating stormwater drains.
One of the main concerns raised at the seminar was the health of the Bay, and how it is believed to contain excessive nutrients, and how stormwater is a large conveyor of nutrients from natural debris that is composting in the stormwater systems. When it rains, the nutrients from the decomposed leaves and grass clippings flushes out to the Bay. Currently, the City of Aventura and Miami are implementing storm drain filters with expanded street sweeping, said to be effective in keeping debris out of the stormwater system, thus reducing maintenance costs and improving water quality. |
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| | | | | | | | ANALYSIS:
| The City of Miami Beach has tested stormwater grates in the past. During a pilot program, the City installed inlet grates along Ocean Drive, from 5th Street to 12th Street. However, the program was unsuccessful.
During rain events, the flowing debris would get caught in grates, causing the drains to clog. These clogs would then create flooding within the streets and sidewalk cafes. The flooding was predominantly present at the locations where the grates were installed. The City received numerous phone calls, service requests, and other complaints regarding the ineffectiveness of the grates during the time they were installed. Attempts were made to have the grates’ performance from the pilot program optimized by the vendor, however, the clogging and flooding persisted.
Since litter and debris would be caught within the stormwater system, prior to discharge by the existing water quality treatment devices (inlet sumps, bar screens, vortex units etc.), City staff determined it was best to have the grates removed in order to reduce flooding.
FISCAL IMPACT:
The fiscal impact of installing stormwater inlet grates would largely depend on the amount deployed. However, the capital expense, and recurring operation expense to clean the grates is not recommended. The existing stormwater system design delivers the same level of water quality benefits without additional operation or capital expenses. |
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| | | | | | | | CONCLUSION:
| It is important to note that the City’s existing pump stations include various stages of treatment that would capture litter and debris. Additionally the new generation stormwater treatment systems being implemented in projects such as West Avenue, also include wells to sequester contaminants.
Since previous experience using grates has resulted in additional flooding without significant benefits beyond what is already provided, the Administration recommends against using stormwater inlet grates and concluding this item. |
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| | | | | | | | Applicable Area
| | South Beach |
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| | | | | | | | | Is this a "Residents Right to Know" item, pursuant to City Code Section 2-14? | | Does this item utilize G.O. Bond Funds? | | | Yes | | No | |
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