ANSONIA DERBY LEVEES
LOCATION: DERBY, CT
CLIENT: MUNICIPALITIES OF DERBY & ANSONIA
MARKET SECTOR: PUBLIC
PS&S performed field and laboratory testing study and geotechnical engineering analysis consisting of seepage evaluation for the internal erosion of embankment and foundation material, embankment and foundation stability analysis and settlement analysis for about 1.6 mile long flood control levee along Housatonic and Naugatuck River.
Evaluation was performed in conformance with National Flood Insurance Program (NFIP) requirements of Title 44, Chapter 1, Section 65.10 of Code of Federal Regulations, in order for the levees to be recognized as providing one-percent-annual-chance level of flood protection. In order to achieve this, PS&S performed seven test borings, performed aquifer permeability tests and detailed engineering evaluation consisting of deep seated stability and internal seepage analysis. Laboratory program was conducted to confirm design soil parameters.
PS&S analysis concluded that the seepage flow through the levee was not detrimental to the stability of the levee via internal erosion and seepage forces. PS&S also evaluated long term creep related settlement of the levee due to deep seated soft compressible organic soil deposits.