Older:
Flood Studies while at Rettew Associates (mainly for bridge replacements):
Storm Water runoff troubleshooting
ONTELAUNEE DAM BREACH ANALYSIS
Ontelaunee Dam in Berks County, Pa. impounds Maiden Creek to form the 1,082 acre Lake Ontelaunee. Envalue Engineering recently worked with Spotts, Stevens, and McCoy (SSM Group) to update the breach analysis for the dam. Also included was determination of the inundation zone for the 3 mile long portion of Maiden Creek located downstream. This project was part of the Emergency Action Plan update for the dam, which must be approved by the Pa. Department of Environmental Protection (Pa DEP).
The project involved an Unsteady Flow analysis in HEC-RAS using a combination of eight new cross sections immediately downstream of the dam, plus a 1985 DAMBRK analysis prepared by a previous Engineer. After developing a working Unsteady Flow model, Envalue Engineering was able to satisfy Pa DEP standards, and prepared a report indicating that the inundation zone from the previous Emergency Action Plan was still valid. Pa DEP agreed and on January 5, 2018, granted approval of the Overtopping and Breach Report, satisfying that portion of the Emergency Action Plan update.
Other Recent Projects:
Bio-Detention Basin
In 2001, Lancaster County constructed a skateboard park within Lancaster County Central Park. In the same area of the park an existing parking lot and compacted baseball fields created a runoff problem. In order to address the runoff problem and meet Lancaster City storm water runoff requirements, Andy (in his capacity as an Assistant County Engineer) designed a bio-retention basin. The photos shown here depict the changes in the basin over time as native vegetation took over the area, and wildlife began moving in.
Copyright © Envalue Engineering. All rights reserved.
Sometimes the solution to a runoff complaint is as simple as pulling a recycling bin out of the storm pipe it was stuck in. Unfortunately the solution isn't always as obvious as this, but experience is definitely an asset when tracking down the source of the problem.
This is also a good example of hydraulics and the power of moving water, even on a small scale.
Disassembly of a covered bridge for County of Lancaster
Rettew Mill covered bridge near Akron, Pennsylvania was located at a tight curve and was frequently hit by cars and trucks. It was replaced by a concrete bridge just upstream. The covered bridge was carefully disassembled and stored for several years until it could be reconstructed in a better location nearby. As part of the project Andy drew a three dimensional model of the bridge (viewable here).