National Diversified Systems (NDS), a plastic trench drain manufacturer based in California, has a dazzling display of trench drain systems that appeal to homeowners and contractors alike. This 3 inch wide channel system comes in 6 foot long, easy to install sections. This product is popular because of its simple construction and inexpensive price. However, a large portion of its allure also comes from the variety of grating styles it has available.

The most common grate for the Mini Channel is the standard 3 foot long gray plastic grate (shown on the right). NDS also offers a plastic grate in 5 other colors (white, green, black, red, and sand). For those with a more discriminating taste, NDS offers two simple brass options (shown on the left). The one foot long brass grates are slotted and come in a satin or polished finish. Besides being simple, shiny, and elegant, they contain chamfered holes for optional screw placement which help to keep them fastened to the channel.

Decorative, cast iron products have recently become available for Mini Channel customers.  The cast iron grating product lines offer a beautiful side to what may otherwise be only functional. Currently, three styles of cast iron grates work with NDS’ Mini Channel: the Interlaken, Carbochon and the Minione. These products are not ordinary slotted grates. The Interlaken is an intricate geometrical pattern while the Minione has a flowing design.  Meanwhile, the Carbochon has a bold presence that only accentuates its open area.

 

 There are a few basic differences between the three Mini Channel grates. Style aside, the grate’s channel fit is the next most noteworthy difference. A comparison of the three grates illustrates this difference.

 The Minione is a thinner grate than the Interlaken. It does not rest in the channel with the same depth that Interlaken and Carbochon do. One gets the feeling that the Minione sits on top of the drain, rather than in it.

This could mean that the Minione grate is more susceptible to become dislodged than the other. The Minione grate is designed with two dimples that are the locations for optional screw holes (they do not come pre-drilled). If used with screws, the Minnione becomes as reliable as any other grate in its class. Another small difference between the grates is the length. The Interlaken (11″ long) is about an inch shorter than the Minione (12″ long), and the Carbochon (14” long) outdoes both grates by inches.

 

Cast iron is the standard material used to make these decorative grates. Cast brass, bronze and aluminum products can be manufactured for an additional cost. We should note that cast iron grates are uncoated and will form a rust coating. In some cases, the rusted look can be endearing.

If your situation doesn’t support this view, though, consider painting with an epoxy or powder coating.  I had two samples of the Mini Channel grating painted because I was curious to see exactly how the process would affect the grates’ performance and appearance over time.

The results, if I may say, are charming.  The powder coating process smoothed out the natural texture of the cast iron grates, giving them a softer, less metallic look.  You can really feel the difference between the painted and baked on oil finishes; the process encased these grates in paint rather than changing their outer layers.  One particularly interesting fact to note:  the grates shown to the left have been painted neutral colors – black and dark brown, but with a purchase over 60 LF a wide variety of colors can be chosen from.  Wowzer!

 

 

Let me just demonstrate the difference between the two available finishes in another way.  Look at the Interlaken grates shown below:  in terms of color, they are very similar.  But, if you look closer you can see the different shine, the thickly coated surface of the grate on the right.  It’s been powder coated.  The grate on the left, though, has a baked on oil finish.   I’ll leave you to decide which one you like better.

 

Cost is all in a person’s perspective, especially when talking about trench drain products. A simple plastic grate that comes in six basic colors is available for a very low price per foot. NDS’ brass grate, a beautiful, no-hassle solution for those still worried about rust or decor, is the most expensive. The cast iron grates, which add style and variety, come for the more moderate price that falls somewhere in between and have beautiful finish options. They are the true extra mile, the art to efficiency, and are the balance if a cost-efficient and stylish grate is desired.

 

Trench Drain in the Amazon Region

If you want to evacuate a large amount of surface water in a short period of time, trench drain is the best way to do it. And, where is one of the best places in the world to find an abundance of surface water? The rain forest in northern Brazil.

I went to Brazil’s northern states of Amazon and Para’ to see first hand how trench drain is used to help in surface water drainage. First, I visited Manaus, the capital of Amazonas state which has about 3,000,000 inhabitants. Thereafter, I flew to a small mining community of Porto de Trombetas, in Para’ state. Though only 7000 live here, Trombetas has the largest metallurgical grade bauxite mine in the world and is the first ISO 14000 city in the western hemisphere. Besides being in the heart of the rain forest, they are ground zero for big daily rainfalls and surface water evacuation.

Trenches without Grates

Maybe the best trench for water evacuation is one without a grate. Creeks, streams and rivers don’t have grates, why should trench drain? Of course, in urban areas, we have safety issues that force us to use grates so we can walk and drive over the trench. Grates also help separate large debris from entering the water ways.

However, all grates can constrict flow; either by design or by collecting trash which further constricts flow.

In rural areas, like Trombetas, grate-less trenches seem to be common.  They are used around the yard to collect water from the roofs.

 They are used at the carport and at the driveway entrances. I guess, if you make the trench narrow enough, you minimize the risk of having someone hurt themselves from stepping in the trench.

 

I suspect, the folks in the rain forest are more concerned over living with water than they are living by lawsuits.   Near the city square in Manaus, I found this 8” wide trench drain that looked as if it once had a cover of some sort.  With the cover gone, it is easier for trash to collect in the trench, thus making water quality more difficult to maintain.

Trenches with Concrete Covers

Concrete is an inexpensive and “low tech” material. Concrete commonly finds itself as a trench covering material in regions of the world where metal products are precious or where labor rates are low. (Has anyone counted missing manhole covers in Detroit, lately?) However, I was impressed how large surface drainage was accomplished without the obvious use of metal grates.

In most cases, the areas that used concrete drainage covers were predominantly for foot or light vehicle traffic (Class A or B). Though the drainage trench may have been covered by a low open surface area concrete cover (sometimes 0% openings), grate sections existed that accepted larger flows.

One exception to this observation was found at the Airport at Manaus. The trench covering was made of individual concrete “plates” which stood on end, packed together as if on a book shelf. The individual concrete sections made up the veins of the grate which supported aircraft traffic over the trench drain. I was sufficiently impressed.

Crude Metal Trench Coverings

If you need a trench covering in a high traffic area where bulky concrete grates will not work, an inexpensive metal covering is the next option. Sometimes, you need to just keep people from stepping in the animal drippings off the butcher’s table or make the entrance to your store a little smoother. A simple flat metal or rebar grate may be all you need.

 

However, if you need a trench grate that needs to be stronger for high foot or automobile traffic, bar grates are a good option. Just make certain that the bars are thick enough to support the load that is being supported.

Solid metal trench coverings were found in automobile traffic areas.

The best covers seemed to be made with thick plate and with a reinforced edge . However, a poor frame design may cause premature failure leading to the drain covering to dismount.

Engineered Metal Grates

Lastly, I was able to find engineer bar grates…ones that had cross supporting metal bars. These are usually more difficult to manufacture and show a little more sophistication than a simple bar grate. These products were found only in the mining town of Trombetas. Examples of this grate type were found at the swimming pool, at the bauxite processing plant and at the mine’s green house.

In this final photo from this trip you see me (author) at the tree farm that the mine owns. I am standing on an engineered metal grate made of aluminum (this is a metallurgical grade bauxite plant). I am wearing traditional Gringo attire — camo shorts and a flowered shirt.

A wonderful point to make about this photo is the purpose of the tree farm. Prior to the mining of the rain forest, an inventory of the vegetation is made. After mining (and the return of the original top soil), trees are again replanted with the species and in the proportions that were taken from the original forest. This is an integral part of the mining operations at Trombetas and a testimony to Brazil’s respect for the world’s last great wilderness which they hold.

Summary

Trench drain is alive and well in the rain forest. The drain channel bodies are cast-in-place concrete. The trench coverings, if they exist, are made from concrete and bar stock steel. No cast iron grates were seen in this region during my visit. To the best of my knowledge, no preformed or pre-engineered trench drain systems are available.

My daughter, Ligia, was in from Brazil to visit in March. We took one weekend and went to Washinton DC to see some sights. The weather was sunny, but cool. (I think I got sun burn and wind burn at the same time.)

While checking out the monuments (and getting a little sentimental), I was able to look at some trench drain. Let me show you two that were interesting to me.

Trench Drain at the Lincoln Memorial Steps – These drains must have looked beautiful when they were originally installed at the base of the granite steps leading up to the Lincoln Memorial. Now they sport a handsome green oxidation coat, which means the original finish must have been a brilliant bronze or brass. These 4″ wide drains are filled with dirt and sediment, an indication that they probably are not pre-sloped. (Maybe, also, an indication of the maintenance budget.) I’m not certain they are really needed here, anyway.

The monument would probably look nicer if these drains were put into service again. Any volunteers to help clean these out?

Trench Drain at the Native American Museum – If you like Native American culture and artifacts, this museum has something for you. I was impressed with a number of aspects of the building’s architecture. The granite trench drain grates running through the courtyard and water sculpture areas, in particular, caught my eye.

These grates are probably the most expensive pedestrian grates I’ve ever seen. Let’s not even talk about the percent open space for efficient water drainage…… You can see they are ADA approved, but I’m not certain if they are heel proof. Are those holes 3/8″ diameter or smaller ???

No matter, the weekend was beautiful and educational. Maybe you have a unusual trench drain system or grate you want to share. Let me know. Thanks……………….  Michael