Published September 2007
Tough to Reach
By Jim Aanderud (page 78)
The right equipment and a little creativity can help work crews perform high-quality inspections in the most challenging places.
In a perfect world, sewer and storm drain manholes would always be in easy-to-reach locations. CCTV inspection vans and maintenance vehicles would then be able to drive right up to a manhole, and crews could inspect with little difficulty.
But anyone who has been in the industry for any length of time knows that is not always the case. This is not a perfect world, and often manholes are located in very challenging places. Sometimes, a manhole location seems to make no sense at all — one gets the impression the system was designed to make access as difficult as possible.
The fact is that many pipelines in service today were installed long before the roads or buildings were built above them. Just getting to these out-of-the-way manholes can be a chore. But carrying a 25- to 200-pound camera and crawler to the site can seem daunting. And of course, the inspection must be carried out successfully as well.
Unfortunately, most agencies have areas that are difficult to reach, whether in back yards, forests, swamps or canyons. At some point, every CCTV inspection crew will be faced with a challenging access point. Successfully inspecting the pipeline will require common sense, a lot of creativity and the will to get it done. And a lot of sweat, too.
Close to the road
Most manholes in easement areas are found only a few feet from the roadway. In these cases, the inspection van can stay on the roadway while a cable is strung to the manhole. In other cases, the inspection van needs to navigate over sidewalks and fields to reach a favorable spot close enough to the manhole so that the cable can be strung to it.
These are simple setups that don’t require much more effort than a standard inspection. They are accomplished by using a top-hole-roller and a down-hole-roller. Once the cable is set, the camera can roll, and the inspection will run just as easily as if the van were parked right over the manhole.
Then there are cases where the inspection van cannot come any closer than a hundred feet or more from the access point. There may be walls, fences, trees, or even streams preventing closer access. This does not mean the inspection can’t be done. It just means it will take a little more effort and a lot more ingenuity.
For the most part, long-range access inspections can be completed with a standard inspection van. However, more personnel are required. The van should be backed in and situated at a point that has the most direct line of sight to the manhole. The cable can then be strung to the manhole.
It is a good idea to remove the cable from the crawler and carry these parts in separately. Most of the time, the cable can be carried to the manhole. However, if there are obstacles such as cliffs, wide streams or heavily vegetated gullies, it may be necessary to throw the cable over the obstacle. In such cases, take care to protect the connector assembly, as it may strike a hard object and become damaged. A protective wrapping should be placed around the unit.
Slowly and carefully
Getting the camera and crawler to the manhole can be very dangerous both to the person carrying it and to the equipment. The key is to transport it slowly and carefully.
Once the cable has been strung out to the manhole, the camera and crawler can be attached. For small-diameter lines, the camera can be lowered into the manhole by hand. However, for the larger crawlers, a tripod should be used as the lowering device. Unfortunately, this adds another piece of equipment to be carried in.
Once the camera is in the line, take all slack out of the cable. Protect the cable with block-and-tackle wherever it makes a turn and will rub against an object. Again, use a top-hole roller and a down-hole roller to protect the cable to reduce drag.
Before the inspection begins, position a crew member at the rear of the van and another at the manhole. Because of the excess cable and multiple turns through the trees, the crawler will experience greater resistance. Therefore, each crew member should assist the crawler by steadily pulling on the cable. Their job is to ensure that the footage counter is accurate by keeping the cable taut.
Use a two-way radio to ensure communication and make sure the crew member at the manhole knows when the crawler is moving and when it is stopped. Without this knowledge, extra cable could be fed into the line, making the footage counter inaccurate.
Off-road vehicles
The mark of a successful off-road inspection is that the final video appears the same as in an inspection performed under normal conditions. The crawler should travel at the same rate, and the footage counter should operate normally. The footage counter should not be running while the camera is stationary, nor should it be stationary while the crawler is traveling. A video like this can be very confusing, and such a defect can be grounds for rejection.
It isn’t always possible to string a cable to a manhole. Whether the reason is long distance or impenetrable obstacles, alternative methods are available. Portable equipment is the ideal solution. This equipment allows you to conduct an inspection without being tethered to the van. The equipment can be carried anywhere and can be used with your existing camera and crawler.
Portable equipment consists of a control unit containing a processing system and a power supply, a monitor, a laptop computer, a portable reel and cable, the tractor and crawler and, of course, a portable generator. The drawback is that the combined weight of this equipment can exceed a few hundred pounds.
Custom wheels
Many front-line CCTV equipment manufacturers sell portable equipment. The key is to find equipment that works with your existing cameras and crawlers.
Because getting to the manhole may require traversing narrow pathways, rocky stream beds, steep inclines or heavily vegetated areas, some operators choose to use extra transport equipment.
Most CCTV inspection equipment manufacturers offer services to customize vehicles for transporting remote-access equipment. Tom Rebozo, regional sales manager with CUES Inc., explains, “The customers select the type of vehicle they would like to use, and we can customize it to accommodate our remote inspection equipment.”
These vehicles range from 4-wheel-drive trucks to specially outfitted ATVs. The John Deere Gator heavy-duty utility vehicle series is widely used for this purpose; so are various ATVs from Argo.
Richard Lindner, president of Envirosight LLC, observes, “Our remote inspection equipment is designed to easily integrate into any type of vehicle, from handcarts to pickup trucks. We will sit down with the customer and come up with a design that we can fabricate to their specifications.”
Expert choreography
A small utility wagon can be pulled by hand or by an ATV, but many times only brute force and endurance will get the job done. In especially tight areas, a stretcher-like carrying platform can be used to distribute the weight of the equipment between two crew members. Whatever the situation, there is no substitute for planning. Everything must be choreographed down to the smallest detail. Nothing should be left to chance.
For example, since finding manholes in the open brush is a big challenge, perform a reconnaissance of the area before carrying any equipment in. Locate and mark the manholes and identify the best approach to each one.
Also, thoroughly test all equipment before carrying it in to ensure that it is working properly. You can waste time, money and energy lugging a piece of equipment half a mile, only to find out that it’s not working.
Some remote inspections require you to work during low-flow conditions, which means working at night. In these circum-stances, the inspection crew should get familiar with the area during daylight.
A reconnaissance should determine the best pathways, the manhole locations, and any hazards. Markings should be made for easy identification at night. With narrow paths, steep inclines, overhanging vegetation and water hazards, reaching a manhole during daylight hours is difficult enough. At night, the difficulty increases tenfold.
A night inspection is much simpler if you move and properly secure the equipment during the day. If that is not possible, take every precaution when transporting the equipment over hazardous terrain. Plan on using extra help.
Living hazards
Besides challenges in the terrain, there are other hazards to consider during remote inspections. Poisonous plants and snakes are a consideration. Tell crews about these hazards and train them in identification and treatment for exposure.
Areas with poison ivy and poison oak infestation should be clearly marked during daylight hours, and crews should wear long-sleeved shirts and gloves. They should wear high ankle boots, leggings or hip waders as a precaution against snake bites.
You can minimize movement of equipment by setting up at manholes where you can inspect both upstream and downstream. The downstream inspections will dictate where the next setup needs to be. Running through multiple manholes is the most advantageous, and it maximizes production. Unfortunately, there will be times when you need to set up at every manhole.
The bad news is that with many major municipalities aiming to inspect 100 percent of their sewer infrastructures in the near future, off-road inspections will surely increase. The good news is that a properly motivated CCTV crew, given the right equipment, training and a desire to succeed, should be able to rival the speed, accuracy and quality of crews doing standard inspections.
Jim Aanderud is owner of Innerline Engineering, a video pipeline inspection company based in San Diego, Calif.
