Sioux Falls, South Dakota
In 2001 we opened our branch office in Sioux Falls, South Dakota. Nicholas J. Johannsen is president of the Sioux Falls, South Dakota operation of Ehrhart Griffin & Associates, Inc. and is the principal land surveyor and civil engineer.
The Sioux Falls' civil engineering department has a diversified range of experience including:
- Site development
- Site grading
- Street and roadway layout
- Design, parking arrangements for on-grade and structural configurations
- Storm and sanitary sewer analysis and design
- Storm water drainage studies
- Detention facilities
- Soil erosion control installations
- Trail networks
- Recreational facilities
- HEC2 analysis for river flow and bridge design
- Potable water system design
- Elevated potable water storage tank design
- Miscellaneous utility relocations.
- Boundary surveys
- Topographic surveys
- Improvement Location Certificates
- Property subdivision surveys
- Global Positioning System (GPS) surveys
- Aerial photography control surveys
- Construction layout services.