County Rt 37 Flood Study update

I wanted to provide an update to the CR 37 Flood & Drainage Study:

Project Start (B&L Authorization):  June 2024

Study Objectives:

  • Assess risk and vulnerability of the community, including residential areas vulnerable to ongoing localized flooding, based on updated hydrologic & hydraulic assessments;
  • Integrating the information and goals outlined in the 2020 Oswego County Multi-Jurisdictional Hazard Mitigation Plan and associated Town Plans related to disaster recovery and mitigation of recurring localized flooding;
  • Evaluating necessary amendments to existing ordinances, or adoption of new ordinances, which promote reduction of flooding risk and increased resiliency in future development.

Tasks:

Site Reconnaissance and Desktop Record Review will include a detailed review of the contributing drainage area through a combination of desktop review and in-person field assessments.  This review will evaluate land use changes over the last two decades to develop an understanding of how development within the study area may have altered hydrology.  A field survey will be conducted of existing drainage conveyances and structures, including types, materials, and sizes, to assist the development of hydrologic and hydraulic models of the study area, as well as an inventory of any potentially deficient areas of the drainage system and stormwater infrastructure. 

Hydrologic and Hydraulic Analysis – Baseline hydrologic and hydraulic models, focusing on stormwater infrastructure within the study area particularly within flood prone areas within the study area’s downstream extent, will be developed. The baseline models will be used to identify runoff volumes and discharge rates for study area and to identify deficiencies in the drainage system (i.e. undersized culverts, lack of stormwater detention, etc.).  The models will develop and graphically document flood profiles, elevations, lateral flood extents and inundation widths within the project area. Following development of the baseline HydroCAD model, historical models will be developed in an effort to identify changes in runoff volumes and discharge rates throughout the last two decades as a function of increased upstream development within the study area.

Local Flood Hazard Analysis Report will document initial coordination efforts, chronology of the work, desktop review and field reconnaissance findings, and the process of formulating existing condition and alternative hydrologic and hydraulic models of the study area.  Additionally, the report will include the following major components in-line with the Town of Hastings’ flood hazard mitigation objectives:

  • Summary of hydrologic analysis methods and flood-frequency discharges for the unnamed tributary of Oneida Lake to be studied;
  • Discussion of hydraulic engineering methods, HEC-RAS profiles and model results;
  • Flood inundation mapping and graphic representations of flood elevations over aerial imagery and topography;
  • Assessment of impacts to residential properties where increasingly frequent instances of localized flooding have occurred;
  • Identification of impacts on critical facilities and services;
  • Assessment of impacts on environmental, cultural, and historic resources;
  • Identification of the most likely causes of increased instances of localized flooding;
  • Identification of the extent of localized flooding for multiple flood frequencies;

At the conclusion of this task B&L will present the findings at a Public Meeting.  B&L will incorporate public comments into the final report.

Project Schedule
TaskAnticipated Start DateEstimated Completion Date
Project Kick-OffJune 2024Complete
Site Reconnaissance and Desktop Record ReviewJune 2024Complete
Hydrologic Analysis (HydroCAD)August 2024November 2024
2D Hydraulic Modeling (HEC-RAS)September 2024December 2024
Draft Local Flood Hazard Analysis Report & Public PresentationJanuary 2025April 2025
Final Local Flood Hazard Analysis ReportMay 2025July 2025

Please let me know of any questions or if I can provide additional information.

Thank you,


David R. Hanny, CPESC, CPSWQ, LEED AP
Vice President
Environmental

Barton&Loguidice

Gateway to Oswego County