My job here is a Civil Designer and a Junior Engineer/Engineer-in-Training. I work under registered Professional Engineers, who typically manage different projects and then pass tasks on their projects down to me. No day here seems to be the same, but the majority of the time, I am drafting plans on AutoCAD Civil 3D, performing Stormwater BMP Inspections, Infiltration Testing in the field, preparing Inspection Reports, or doing a variety of calculations. Throughout this newsletter, I have some pictures that describe my experience here so far.
Lot 24 Wrights Lane Stormwater System Inspection – In this case, I was looking for any obstructions or excessive sedimentation in the Terra-Kleen system, which is part of the Stormwater Management network and serves the purpose of removing pollutants before the water is discharged or infiltrated.
In four months, I think I have learned more than I did in four years of engineering school. The same principles of success still apply here, like respecting the people you work with, being dependable and communicating, but actually taking engineering concepts and applying them to the real-world projects provides a much deeper understanding than just talking about it in a classroom.
Tri-M Group Sketch Plan – The Tri-M Group is a long-standing business in East Marlborough Township, Chester County, Pennsylvania that services the tri-state area as an electrical contractor. The Tri-M Group provides our community with approximately 500 jobs and is continuing to grow, and this preliminary sketch is for a building addition at their headquarters that will serve as a new safety training area. This site is currently in the process of being surveyed and the next step will be land development plans.
There have been some situations I’ve been put in here that I wasn’t exactly comfortable, like talking to three attorneys on the phone at one time, but that is how you learn and grow. There have been times that I have really enjoyed here as well, my favorite being operating the excavator for infiltration testing.
Chester Community Charter School Infiltration Testing – View from the back of the International Commercial Towing Truck that is used to transport the mini-excavator. The truck weighs approximately 25,000 Pounds without the excavator loaded.
On a typical day that we are going to perform infiltration testing, I would meet Dave DiCecco, DL Howell’s Environmental Specialist, around 7:30 AM to head out with the equipment (Yanmar ViO 35 Mini-Excavator and an International Commercial Towing Truck) to do some digging. During two days on site at the Smith Property, a 19.4 Acre Site in Kennett Square, Dave and I completed ten infiltration tests in different areas of the property that are of interest for stormwater management.
The Smith Property Infiltration Testing– View from the cockpit of the excavator. In this case, we first dug until we met groundwater and to record the soils, which was to a depth of about six feet. Then, we dug out a smaller area to do our infiltration testing at a depth of about two feet. Typically, the infiltration testing would be done around four and a half feet, but, because the groundwater level was high, we decided to do our testing a bit shallower.
The Smith Property Infiltration Testing – Side view of the excavator in another area of the property. The excavator weighs approximately 7900 pounds and has a maximum digging depth of 11.25 Feet.
While digging for infiltration testing looks like fun and games, it serves as an important part of the stormwater management system design process. When you are building something, there is going to be impervious that creates runoff, and a certain amount of this runoff (dependent upon the township your project is in) has to be infiltrated into the ground on site.
The Smith Property Infiltration Testing – At this infiltration testing site, the groundwater level was about nine feet, so we were able to do our testing at about six feet.
To infiltrate your runoff on site, there are typically two main tools used, one of them being an infiltration basin and another being an infiltration bed. Basins are often used in developments where there is more open space, while beds are used where there is less open space, like in an urban area under a parking lot. By doing infiltration tests, the rate at which the water will seep into the ground can be determined (hydraulic conductivity is the fancy name), this is important to know when sizing your basin or bed to dewater within the required 72-Hour PADEP period.
Manfredi Cold Storage Infiltration Bed Inspection – At this location, an underground infiltration bed is being constructed. After this infiltration bed is completed, a parking lot will be constructed above it. G & A Clanton, Inc., out of Avondale, Pennsylvania was the contractor on this job. My main purpose for going out to inspect this bed was to ensure that it was being built to the specifications noted on the proposed plan.
Above, an infiltration bed can be seen. In this case, the infiltration basin was chosen to mitigate stormwater runoff due to space limitations. Below, an infiltration basin and detention basin can be seen. Infiltration basins are meant to infiltrate runoff while detention basins are meant to slow down and control the flow of runoff. Detention basins are often used to protect floodplains and creek beds from unhealthy increases in flow and sediment.
Oakcrest Stormwater Management Inspection – This is an infiltration basin; there is an inlet structure on the right side of the basin that allows water collected by the inlets along the street to flow into the basin. There is an outlet structure, without an orifice, that allows the water to flow out of the basin in the case of a massive storm event when the basin is completely full.
Sage Hill Stormwater Management Inspection – This is a detention basin, there is an inlet structure on the right-hand side of it that again allows water collected by the inlets along the street to flow into the basin. The main difference in a detention basin when compared to an infiltration basin is that the outlet structure contains an orifice that allows water to flow out of the basin in a controlled manner during smaller storm events. In this case, there is a creek over the berm at the other end of the basin, so this basin was most likely put in place to protect it. There are some maintenance issues with this basin that are currently in the process of being remediated.
Camphill Village Kimberton Hills – An AutoCAD Civil 3D sketch of a proposed 6210 SF building with 26 parking spaces, the two closest to the building will be handicapped spaces, which is required by the West Vincent Township Ordinance. The green dashed line surrounding the building and parking is the limit of disturbance, while the solid yellow line is the drainage area that will be used for stormwater management calculations.
Because I have been out in the field so much during my time here so far, I have learned that it is important to listen to the construction workers/contractors and be humble when doing so. They are the ones out there everyday building what has been designed, so they may have some input that you did not necessarily anticipate during the design process. Sometimes, builders will look to you for answers to their questions, and because there is so much to learn in this industry, you won’t always know the answer at first, but you can almost always work to figure it out. For all of these reasons, civil/environmental engineering is a pretty tough industry to enter, especially when you are a younger person just coming out of school, but I look forward to the future and think it will be worth it in the long run.