Miami-Dade County High Point Trip Report

Date: December 23, 2000
Author: Mike Schwartz

The true natural high point of this county is still unknown. I had convinced myself that the 35+ ft. elevation at the northwest tip of Virginia Key might be natural, but I no longer think so. Here's a rundown of my explorations:

one small area in Section 21-52S-42E, possibly manmade (35+ ft)

See Fred Lobdell's report. His directions work fine, except that FL 826 in the vicinity of US 1 is not Golden Glades Drive, but rather Miami Beach Blvd/163rd St. I first checked out the small 20+ ft. area just south of 151st St., which forms the northern border of this area. 151st St. is the access road to the Florida International University campus from US 1. Signs on 151st St. warn of unstable ground and hidden objects in the woods to the south. I entered the woods in two different places, and although the land does slope uphill toward a closed 20' contour, the whole area is a jumble of land fill debris. There's fairly mature vegetation covering the debris, so the landfill must have occurred several years ago. This area need not be visited.

The 25+ ft area under the "1" in the section "21" number on the topo and the tiny 35+ ft area nearby are a mess. Following Fred's lead, I parked in the rear of the Costco store on the east side of US 1, and entered the unposted woods from the north end of the lot. Besides dog waste and assorted trash, the first thing I saw in the woods was a homeless gentleman living in a tent, no more than 50' in from the lot. I bushwhacked east and soon intercepted one of the track roads Fred mentioned, which led past one of the bodies of water visible on the topo, which now has water in it. The partially overgrown track road led slightly uphill to a T-intersection with a north-south trending track road, and I felt after all the wandering that this T-junction was the highest ground I found. I wandered several other track roads, but found no higher ground.

Returning to the car, I decided to look for an eastern approach from the FIU campus. Driving north on US 1 from Costco, I turned right onto 151st St., which becomes Bay Vista Blvd., as it curves south toward the FIU campus. About 150 yards south of the main entrance to the campus, look for an obscure track road on the right, barred by a chain link fence about 30 feet in from the main road. This road is not posted, and you can walk around the fence. The road, which looks to be very lightly traveled, is on a pine needle covered embankment that meanders through a very dark mangrove swamp. I flushed a large egret and a great blue heron at close range on this stretch. The road eventually leaves the swamp and climbs gradually through mixed woods. After about 1/2 mile, reach an open area with what looks like a berm and several well caps or drains. From here, take the dirt road that goes most directly uphill and keep working uphill for maybe another 1/3 mile, marking the route of return at the several look-alike junctions. Finally reach the largest clearing by far, at one edge of which there are some obviously long-established manmade fill piles that could well mark the tiny 35+ ft. areas shown on the topo. This area is definitely close to US 1, as the road noise and loudspeaker announcements can be heard clearly, as they can be from the track roads behind Costco. I did not choose to bushwhack all the way to Costco, but it was close.

The big question is whether any of this area in Sec. 21 is natural. I suspect that the original base was no higher than 10-15 feet, and that the rest is fill. Everywhere I looked on both the east and west approaches, there was extensive disturbance, and every so often a large clunky block of obvious fill would still be visible sticking above ground. In my opinion, the area cannot in good conscience be declared clearly higher than any other 20+ ft. areas in Miami-Dade.

one area 1/4 mile north of Sewage Disposal, possibly manmade (35+ ft)

From I-95 take the Rickenbacker Causeway ($1.00 toll eastbound) toward Key Biscayne. After passing Miami Marine Stadium, go left at a large sign for Virginia Key. This is a Miami city park, and the entrance fee for non-residents is $5. I handed the toll taker my pass from my earlier visit to Greynolds Park, a county park, and since it was Christmas, he honored it.

From the Rickenbacker Causeway, drive 0.5 miles to the fork shown on the topo, bear right, and reach the entrance to the sewage plant at 1.4 miles. Go right, pass some windsurfer shacks, and reach a no trespassing sign at 1.6 miles. The walk from here is a short one, but the area seemed very quiet on this Saturday, so I drove through. The pavement ends at 1.9 miles, and you can drive another 100 yards or so to a chain link fence, where on this day a Cadillac was parked, with no sign of the owner. The fence, marked as county landfill, runs east-west along the northern edge of the sewage disposal area shown on the topo. At the east end it runs several feet into the water to make walking around it difficult, but some kind soul has cut a large hole about twenty feet above the beach. Once inside the fence, follow it back west to a road that parallels the fence line and leads to the large depression contours southeast of the 35+ ft. area. When the depressions come into view, head straight across them to the skyline to the NW, aiming for huge concrete blocks piled on top. Two roughly parallel dirt roads run over the top and the length of the highest ground. The whole area is composed of coral rock, and is being mined away, rather than being piled up. The road on top the hill nearest to the water runs through a five foot deep cut, exposing the rock. My initial opinion was that the rock looked undisturbed, but after sleeping on it overnight, I suspect the rock is what was excavated from the sewage disposal area to make the holding basins. It's now being mined away, and someday the island may regain its original contours. There is no sign of any dune deposits, which could have been natural. One of our geologists living in Florida needs to check out the road cut on top the hill to be sure.

Virginia Key, possibly manmade (30+ ft)

At the fork 0.5 miles in from Rickenbacker Causeway, bear left and drive another 1/3 mile to the large transmission tower. A driveable dirt road goes along the south side of the tower toward the 30+ ft. area. Southeast of the tower another dirt road leads through a tree line into an open field, which seemed to contain the highest ground. I checked out the woods at the edge of the large clearing, but the ground did not go uphill significantly. This area shows obvious signs of landfill, and its status as a natural feature is questionable. The large septic plant just to the north may also be the origin of its raised elevation.

Greynolds Park in Section 9-52S-42E (20+ ft) [not listed in "County Highpoints"]

See Fred Lobdell's report. It is correct, except that the fee is now $3, and the man-made mound was not built for children, but rather as a means to separate gullible highpointers from their money. Save your money, but if you do go, save the parking stub, which is good for the day in all county parks.

Amelia Earhart Park in Section 29-52S-40E (30+ ft) [not listed in "County Highpoints"]

Thanks to John Mitchler for a complete list of all areas in Miami-Dade at least 20 ft. in elevation. I had time for one more stop today, so I opted to visit the highest point left, the 30' bump in Amelia Earhart Park. The entrance is just north of the junction of Gratigny Drive(65th St.) and E 4th Avenue, south of Opa-Locka Airport. The 30' knob is obviously manmade, no doubt with the fill from the excavation of the two ponds nearby. Save your $3.

Unless a Florida-based geologist can declare either of the Virginia Key areas to be natural, there are some 22 other probably natural 20+ ft areas in Miami-Dade that John Mitchler has identified. Visiting them will be a long day's work.