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HomeMy WebLinkAboutSubmittal-Robert Weinreb-Virginia Key Boat Ramp AssessmentSubmitted into the public record for item(s) on 3 •24-.to _ City Clerk LEGEND: 1- Marine Stadium Basin rties oric Virginia Key Beach Park Site 3- North Point 4- old Landfill 5- Beach and Hammock 6- Shrimpers Lagoon and Treatment Plant 7- Critical Wildlife and Conservation Area 8- Miami -Dade County Property, Seaquanum and UM Rosentiel School Iln-Ualu3-SUbmittUl- Kau f- Vv2i�1r2b-v1tGiYlIG 1=e1 boa 1- 12UrY�V Ps she Ssrn2 n t- APPLIED TECHNOLQGY & MANAGEME1 T 400 5. AUSTRALIAN AVE . surTE ado WEST PALM BEACH. FL 33401-5045 (561) 559-0041 FAX 559-3133 NAM APPLIEDTM CAM MEMO To: Paul Kissinger (EDSA) Swati Khimesra (EDSA) From: Greg Kelahan RE: Virginia Key — Boat Ramp Location Assessment Date: July 2, 2008 cc: Mike Jenkins (ATM) Submitted into the public record for items) C A • 5 on 2 '2,4' ) L , City Clerk NDU On Wednesday, June 25, 2008, ATM representatives (Michael Jenkins, Ph.D., P.E., Greg Kelahan, E.I) visited the location proposed for a boat ramp on Virginia Key. City of Miami representatives Perla Gonzalez (Planning Department) and Robert Weinreb (Office of the City Manager) were also present. The site proposed for the boat ramp is located along the northeast side of Virginia Key, adjacent to the northeast corner of the existing wastewater treatment facility property, abutting Norris Cut. Site visit photos are included with this document, and site visit observations are as follows: Site Observations Shoreline Condition — The shoreline consists of fine sand dominated system that shows evidence of human impact. Assorted debris including construction materials, derelict dredge pipes, and evidence of spoil material placement were noted in the vicinity. Existing Depths — Water depths within Norris Cut generally range from 2 to 6 feet. However, depths of 8 to 12 feet can be found in the channel adjacent to the boat ramp site, in between Virginia Key and Fisher Island (to the north), and adjacent to Fisher Island. The nearshore slope is approximately 1V:201-1. Thus, approximately 200 feet of excavation would be required from the shoreline to reach channel depths. Seagrasses — Seagrass was observed in the nearshore region adjacent to the boat ramp site. Seagrasses in this area are also evident in readily available aerial photos. Observations were consistent with those reported by Gary Milano (BERM) in an email to Enrique Nunez (Planning Department), dated April 15, 2008, which noted the presence of Shoal grass (Halodule beaudettel), Turtle grass (Thallassia testudinum), and Manatee grass (Syringoduim filiforme). Spoil Material — Spoil material (likely from a nearby environmental restoration project on Virginia Key) was recently placed on the upland between the existing wastewater treatment facility and the proposed boat ramp location. This material was observed during the site visit (6/25) and is visible in the aerial photo (5113) below. The material is poor quality for placement on a beach, has a large amount of vegetative debris. and appears to have high silt content. Evidence of uncontrolled runoff into the open water was observed from this material. Environmental & Coastal Engineers, Scientists & Management Consultants Memorandum To: EDSA Date: July 2, 2008 Page 2 of 7 Submitted into the public _ record, j for item(s) j({} On e. 4 ) 4f'f City Clerk Site Access — The majority of the existing roadway on Virginia Key leading from the Rickenbacker Causeway to the proposed boat ramp site is in fair -to -good condition and would pose no access issues for vehicles with boat traders. Coastal Processes — Sediment transport along this shoreline appears to be low and the ramp location is at the boundary of the littoral cell. This implies that the facility could be constructed with minimal impact to the coastal sediment transport system. Miscellaneous Notes/Observations • No manatees were observed in the area during the site visit. • No evidence of sea turtle nesting was observed during the site visit. • The shoreline has relatively low energy waves and limited sediment transport. • The site has been previously impacted. • The site is located near Jimbo's, which has existing boat moorings and infrastructure. • Discussions with City of Miami Police Marine Patrol officers indicate the area is heavily used by boat traffic. • Adjacent upland area (next to wastewater treatment facility) is well -suited for parking. ■ Existing upland vegetation in the vicinity consists largely of exotic species; limited upland mangroves are adjacent to the proposed ramp site. Site Comments Based on a review of the draft boat ramp area plan and considering site observations, the following comments are provided: • The ramp would result in direct impacts to seagrass species, with a magnitude of direct impact on the order of 0.5 to 1 acres. • The ramp will result in potential secondary impacts to seagrasses. • The ramp may result in potential impacts to sea turtles. • The ramp may result in potential impacts to manatees. • The proposed ramp site does offer opportunities for avoidance and minimization of impacts exist given detailed siting efforts. Given the existing condition of the area, there are a number of potential mitigative actions, including: • Regulated navigation channel (channel markers, slow speed zones, and enforcement) that may reduce potential impacts to seagrass and manatees. • Debris removal. • Upland exotic vegetation removal and replacement with native vegetation. • Establishment of natural beach/dune system conducive to sea turtle nesting. • Removal of non -compatible beach material. Environmental & Coastal Engineers, Scientists & Management Consultants Submitted into the public record for item(s) - - ,-- Memorandum on City Clerk To: EDSA Date: July 2, 2008 Page 3 of 7 • Site erosion stabilization to reduce runoff, providing a net benefit to nearshore water quality. Alt of these mitigative actions are compatible with implementation of a boat ramp in this location. Site Assessment Permitting of any new facility in the coastal zone is always a challenge. This site is not free of potential issues that would be considered during the regulatory review- Major issues that would need to be satisfactorily addressed include: Seagrasses • Direct impacts and the need for mitigation. • Necessity of an accurate and detailed seagrass assessment. • Establishment of a navigation channel as mitigation, though additional mitigation may be required. • Detailed seagrass survey will likely be required, and the exact location of the boat ramp should be adjusted within the general area discussed herein, in order to minimize impacts to seagrasses. • Argument can be made that constructing the proposed boat ramp in conjunction with the loss of the existing boat ramp near Coconut Grove could result in lower transit density within seagrasslmanatee zones in Biscayne Bay, potentially decreasing opportunities for impacts to seagrasses. • Further coordination with regulatory agencies will be required to fully assess the issue. Sea Turtles • Subject site has been referenced as sea turtle nesting habitat (G. Milano, DERM). • ATM is not aware of nesting density or nesting success rates, but site observations raise multiple concerns relative to the nesting quality of this beach. • Clear opportunities exist to significantly enhance the potential nesting quality of this beach. • Facility lighting should consider potential nesting activities. • seagrass is also a secondary sea turtle issue. Manatees • Area is presently high -use by boaters and adjacent areas are noted for manatee use. • Site is adjacent to a manatee protection area. • Coastal construction at the project site is not precluded within the Miami -Dade County Manatee Protection Plan (MPP). • Site is located within an area considered "Essential Manatee Habitat" by the MPP. • Argument can be made that constructing the proposed boat ramp in conjunction with the loss of the existing boat ramp near Coconut Grove could result in tower transit density Environmental & Coastal Engineers, Scientists & Management Consultants Submitted into the public reef) dpr items) C •5 Memorandum on { �I,�. City +ler To. EDSA Date. July 2, 2008 Page 4 of 7 within manatee zones in Biscayne Bay, potentially decreasing opportunities for impacts to manatees. • Regulated channel and enforcement would help address potential impacts. • Seagrass is a secondary manatee issue. Project Need — When assessing project need, the regulatory agencies will note that Crandon Park is located about 3 miles away by road. Crandon Park has ample parking and the existing capacity to launch/recover 15 boats at the same time. There is also a small boat ramp within Shrimper's Lagoon adjacent to Jimbo's, as shown in the photo below. Conclusions While this site is not free of environmental concerns, opportunities exist to construct a boat ramp facility in this area in conjunction with a comprehensive management and restoration effort. Such an effort would require considerable coordination with a range of State and Federal regulatory agencies. It is also worth noting that no assurance of regulatory approval can be provided. However, a review of the site and draft master plan suggests that there is no obvious "fatal flaw" to the approval process. This being said, given the issues associated with this site, it is reasonable to assume that any permitting effort would require an involved and likely lengthy process. Photo Reconnaissance Aerial of proposed boat ramp location area (5113/08) Environmental & Coastal Engineers, Scientists & Management Consultants Memorandum To: EDSA Date: July 2, 2008 Page 5 of 7 Submitted into the public record for item(s) C R .6 on 1.74. , Citl�l{i�- General location of proposed boat ramp. Note Casuarina vegetation and cleared area. Beach area for proposed boat ramp (looking south). Environmental & Coastal Engineers, Scientists & Management Consultants Memorandum To: EDSA Date: July 2, 2008 Page 6 of 7 Recently placed spoil material. Submitted into the public reco d for item(s) CA 5. on 3 • Li * 1 ii,p . City Clerk Close-up of recently place spoil material - note poor beach quality & debris. Environmental & Coastal Engineers, Scientists & Mcanngeinent Consultants Memorandum To: EDSA Date: July 2, 2008 Page 7 of 7 Submitted into the public record for item s) on City Clerk Ruts indicating runoff from spoil material into open water. Existing boat ramp in nearby Shrimper's Lagoon (at Jimbo's). Environmental & Coastal Engineers, Scientists & Management Consultants Page 1 of 3 Nunez, Enrique Submitted into the public recur for item(s) ( A • 57 on 'Z4� l to . City Clerk From: Milano, Gary (DERM) (MilanG@miamidade.gov] Sent: Tuesday, April 15, 2008 9:48 AM To: Nunez, Enrique Cc: Basu, Subrata (DP&Z); Grossenbacher, Craig (DERM) Subject: RE: Boat Launching Facility At Virginia Key (File minimized to accommodate e-mail capacities) Attachments: Boat Ramp Site Plan.pdf; Virginia Key Map as word file.doc Good Morning Enrique, As a follow-up to our meeting on March 3, 2008, thank you for this opportunity to offer the following information and observations for the proposed boat launching facility located north of the entrance channel to Jimbos' boat basin on Virginia Key: The shoreline at the proposed facility site (see attached site plan) consists ofa continuous sandy beach which provides a suitable substrate for marine sea turtle nesting. NOAA's National Marine Fisheries Service turtle survey datum indicates that 10-15 percent of the observed nesting on Virginia Key occurs within this portion of the island. (Wendy Teas, NOAA) The following criteria are from the Manatee Protection Plan: In order for boat ramp sites to be considered suitable for development the following criteria must be met: • Minimize boat Jmanatee overlap; • Do not cause destruction of submerged aquatic vegetation fed upon by manatees; Boat Ramps are not permitted in areas supporting dense sea grass beds. Since the manatee protection plan was mandated, proposed new boat ramps for powerboat use are not permitted by DERM, unless the applicant can prove that the proposed facility and the boats using the facility will not endanger the manatee. 3. Seagrass Observations: The following in -water observations were made on March 3 12008 at the proposed boat launching facility on northeastern end of Virginia Key: • Shoal grass (Halodule beaudettei) was observed within 25 feet of the mean high water line (MHWL) along the proposed site. The water depth is approximately 0 feet (NGVD) 25 feet offshore the MHWL. • The shoal grass transitioned to various dense mixtures of Turtle grass (Thatlassia testudinunr), Manatee grass (Syringodium filifbrrne), and Shoal grass (Haloclule beaudetteij. Please see the attached photo. The water depth 60 feet offshore the MHWL is approximately -1 feet (NGVD). • A continuous dense bed of seagrass was observed to extend offshore beyond the surveyed area (approximately 150 feet offshore the MHWL). • A than -made depression (approximately 30' X 80') was observed approximately 30 feet offshore within the northeastern quadrant of the surveyed area. This depression was most probably the result ofa previous impact associated with a boat grounding and/or unauthorized prop dredging. • The attached Virginia Key word file snap and Miami -Dade County aerial files indicate shallow dense seagrass beds throughout Norris Cut. As discussed, Norris Cut is too shallow for powerboats to directly access the ocean at low tide from the proposed site. • The Bill Sadowski Preserve and associated marine flora and fauna would be vulnerable to irresponsible boaters taking short cuts to navigate to the Rickenhacker Bridge. To navigate responsibly, boaters will have to detour through Fisherman's Channel (located 7/14/2008 Page 2 of 3 parallel to the Seaport) to access the bay and the ocean. Overall, the natural water depths are very shallow in and around the proposed site, and shallow dense seagrass beds were observed in and around the proposed site. 4. I would recommend that the consultant andlor City contact the Miami -Dade County Planning Department to receive additional comments on traffic issues, etc, associated with this proposal. In addition, please check the existing Miami -Dade County and the City of Miami Comp Plan policies associated with this proposal. FYI, there is usually a general policy not to build government infrastructure in the coastal high hazard area, at least not at elevations below flood criteria and FEMA requirements. Summary: The proposed project will directly impact protected seagrass resources and indirectly impact two endangered species. As a result of the Endangered Species Act and the Protected Resources Rules, the regulatory process will he challenging and if permitted, will most probably require mitigation. The practicality of the site is also a concern. This is a public beach. Do we really want to pour concrete along a beach? In addition, the distance from the Rickenbacker Causeway to the proposed site along Arthur Lamb Road (two lane road) is approximately 2-miles. The roadway has many large speed bumps to restrict speeding. Vehicles and boat trailers would probably have to come to a complete stop to eliminate damaging the boat and trailer. As stated, please contact the Miami -Dade Planning Department Interim Director (Subrata Basu) for additional comments. In addition. I would recommend that the City's Consultant contact the following regulatory agencies for comments on the proposed boat ramp: U.S. Army Corps of Engineers, FDEP, and the DERM Regulatory Division. As discussed, DERM has recommended that this area of beach be enhanced to complement the sea turtle nesting and provide additional public beach. As you are aware, DERM has initiated the enhancement of this portion of beach. In consultation with NOAA, we would like to propose further enhancement of this area of beach through the placement of additional sea turtle nesting sands (approximately WO cubic yards), in the very near future. Please let me know if this would be acceptable with City staff. To assist the Virginia Key master planning process, I would recommend a field trip with County and City master planning staff members and County/City administrators, to further discuss planning recommendations for this portion of beach along Virginia Key. Should you desire additional information, please feel free to contact me at 305.372.6$5 Regards Gary Milano DERfv1 Submitted into the public, record for item(s) _CA .'ID on . 2.4.1 . City Clerk 7/14/2008 Page 3 of 3 Submitted into the public record for item s) CA .5. on ' 2City Clerk From: Nunez, Enrique [mailto:ENunezci.miamifl,us] Sent: Tuesday, March 04, 2008 5:00 PM To: Milano, Gary (DERM) Cc: Gelabert-Sanchez, Ana; Biilberry, Laura; Sanchez, Carmen; Valdes, Madeline; Gonzalez, Perla S.; Weinreb, Robert Subject: Boat Launching Facility At Virginia Key Gary: First of all, thank you for providing us with an update and sharing photos of your marsh restoration work underway. Furthermore, based on our discussion and review of the conceptual boat launching facility design at Virginia Key, please provide us with your observations of the proposed boat ramp site (existing conditions, environmental and biological resources, existing navigation channels) and if you foresee any adverse impacts to the area. Do you have any bathymetrics of the immediate area or delineation of any ocean bottom. resources, grasses, etc.? Please provide us with any information you have as soon as possible so that we may forward it to the team of consultants. Thank you for your assistance. Best regards, Enrique D. Nunez, RLA Chief of Urban Design City of Miami Planning Department (305)416-1419 office (305)416-2156 fax 7/14/2008