We discovered that some manholes were so overloaded (probably by stormwater infiltration into the system) that sewage was flowing out of the holes in the lids meant for the pick handles used to open them. Other lids were slightly lifted allowing raw sewage to flow out all around the rim. In sump conditions the same holes were taking on water that overflowed the manhole. Those that were properly functioning were recorded too. For some malfunctions, like a leaky roof and a leaky sanitary system, you need to check them while it’s raining.
Many states now combine knowledge and proficiency in stormwater management and the related calculations in their professional surveying license requirements. In some states there may also be testing for the design of sanitary pipe runs, roadways and erosion and sedimentation plans.
If you know you are experiencing a 100-year storm and your own house is safe, you might take a drive and see how some finished detention basins are operating. If the water is flowing right in and out of the basin with no visible detention, then it was over designed and made for too large a drainage area. Such a basin never slows water to reduce post construction flows to pre-construction flows. If water is flowing over the emergency spillway, then something has gone wrong. It should not have water run over it except in emergency situations. So was the basin poorly designed? Perhaps the outlet structure is clogged with debris. After the storm, see how well the spillway held up under stress.
Curb inlets can be interesting to observe and watch how the water flows into the inlet, or actually does not. You can witness water flowing past an inlet or possible right over it. On construction sites note what is happening when there are temporary hay bales, rock filters or silt fence over the grate. With flow limited, what is the water doing? Where is the water going?
Hydroplaning is very dangerous so you might notice pavement where the water is too deep. Do you see roads that do not seem to be draining properly? Is water flowing over the curbs? Are streams flowing over the road? Can you see possibilities where things could have been done better and those situations avoided? Can you understand why it is very important that those individuals that design roads, stormwater management and such are not only skilled and knowledgeable but also have the practical experience to see where and why the designs failed?
We use some fantastic computer programs to design stormwater facilities. They produce some impressive reports and charts. We need to field inspect post construction to know if our designs worked.
Some years ago, while I was staking out sanitary sewers in a new subdivision, I had a hunch the sanitary sewers were going to collide with the stormwater lines that were already installed. I brought this immediately to the attention of the designer who had a PhD in engineering. He reviewed his design and saw there may be a problem. My crew met with him in the field to get asbuilt measurements on the pipes and to discuss the situation with the piping foreman who would connect the existing sewer run from the house to the existing sanitary sewer line. I doubt the engineer had ever physically seen the pipes he was designing to be installed. With a ruler he measured the thickness of the reinforced concrete stormwater pipe, the soil line to the house, the dimensions of the bell of the pipe connections and the location and elevation of the home under construction. Although there would not be optimum clearance between the pipes, the run would work.
It was then I understood that the brains in the office had fewer real-world experience than I thought. I am not trying to diminish that man’s ability to design in any way as I think it’s fairly typical. Licensed or not, we are all practicing in our work, and in doing so, learning every day. I have seen these sorts of problems in other areas, too, where items like lift rings and special tops had to be installed to make things work. You may not know when the really good contractors look at your designs and shake their heads and just do it the right way.
If you have the opportunity to watch and listen to engineers and surveyors trying to figure out how to fix a problem, you should listen up. It is easy when things work as planned. Real talents can shine when things fail and practical solutions come about. I’ve always appreciated hearing skilled designers talk out the problems and explain their remedies.
For the apprentice surveyors in training, I suggest that on rainy days you take an hour or more to visit the sites they have staked out to see how the stormwater facilities are functioning. If you are someone paid on a salary basis then it’s a worthwhile mission that will keep you busy and learning while also being out of the critical eye of office personnel. If you are not paid for rain days it is an even better investment of your time because it will help you on the way to licensure, promotion and higher income.
Getting back to our flooded roads and fields, you want to know what stormwater management features look like while they are doing their job. We are part of a team that protects the environment and public safety. Knowledge of functioning and non-functioning systems helps make you a better surveyor.
So next rainy day, give yourself and your crews a rain check. It’s a great investment and an excellent learning opportunity.