During our cleanup on Saturday 10.8.11, the SLDogPAC installed a mesh fabric barrier along the west side of the Grant Bark Park. The fencing fabric is intended to address a problem that is common to poorly designed pea gravel areas in the dog ‘friendly’ areas around Chicago – that is, pea gravel is going to spread out wherever it can!
And, if it’s not contained properly, it’s going to end up distributed all over the place. So, in the case of GBP, large amounts of our pea gravel ended up on the Metra roadway below!
How to do it right?
There are good ways to design pea-gravel relief areas, and we’ve posted an example of a properly excavated space at a local condominium complex before. That area is fairly small, was extensively excavated, and was bounded by landscape ties. It experiences very little gravel loss or gravel dispersion.
We can’t re-excavate the GBP or CPDR gravel areas, so we’ve had to come up with another approach.
At CPDR we’ve implemented a preliminary, labor intensive, and not completely satisfactory fix by installing short segments of screening along some fence areas. These were off the shelf materials from our local home supply store, secured using cable ties.
What did we decide to do?
Our approach at GBP was to purchase and install a continuous fabric mesh along the chainlink fence on the west side of the park. The material is like the construction fencing you sometimes see at construction sites. The mesh was manufactured with metal grommets installed every two feet, facilitating installation. The bottom edge was secured by laying it out so that it could be held down by the gravel layer itself.
The material we used is 60%’ Knitted Shade Cloth by DeWitt, which we obtained from CatalogClearance.com. John and Mike at Catalog Clearance were extremely helpful in putting together this order, sending us samples of different mesh densities to evaluate beforehand, and arranging for it to be prepared to our specifications. The distributer is in Libertyville, IL, so once we placed the order it arrived quickly. The material is lightweight – 175 linear feet of 6′ mesh weighs only about 30 pounds.
We requested the 6′ cloth be cut in half, to 3′ wide, hemmed on both long sides, with brass grommets inserted every two feet along one edge of the material (and at the ends). The total cost including shipping was less than $450.
The installation was straightforward – 6″ segments of vinyl covered wire were preinstalled in each grommet. After clearing away the gravel adjacent to the fence, it was then a simple matter of laying out the mesh alongside, and then walking along and securing it to the chainlink with the wire loops. We extended the fabric about 2 feet up the fence, leaving about a 1 foot extension at the bottom. The job was finished by shoveling gravel over the extended fabric to secure it.
It only took a couple of hours to finish up ~225 feet of fencing mesh. We’ll be out to the park to finish up the north and south ends of the gravel area later this Fall. (We still need to figure out a strategy to secure the mesh to the vertical fence posts there.)
We expect that the mesh will secure the pea gravel area, and that it will allow us to begin power-washing the gravel area on a more regular basis. Previously, any attempt to wash the gravel was going to cause a lot of gravel to be blown out of the park. So the installation means a cleaner and safer park for our dogs.
It’s an important step, one that should have been taken at the beginning.
How bad can it get?
For the uber-example of gravel containment ‘issues’ at a Chicago DFA, take a look at some pictures from the recently developed Montgomery Ward Dog Park in River North.
This park is unique in that the surface is entirely pea gravel and the park is surrounded only by a chain link fence. Unfortunately for the design team at the Chicago Park District, it really is true that chain-link fencing will not retain pea-sized gravel!
Where does the gravel go? Heh. The DFA is surrounded by a halo of escaped gravel:
To DFA Support Committees – it’s important that you contact your Park Supervisor to let them know about an installation like this, and to get their approval. You don’t want a CPD maintenance crew pulling it down because they aren’t aware of the installation!
And yes, we will be passing on this information to the Chicago Park District, in the hope that their future pea gravel ‘design’ efforts can be more carefully thought out in light of the real world experience of those of us who try to maintain these spaces.