MS4 Illicit Discharge Investigation Using Thermal Imaging UAVs

Research and Development, Village of Laurel Hollow, New York Walden, Harkin Aerial, and the Friends of the Bay (Oyster Bay) applied for and received a grant from the Nassau County Soil and Water Conservation District to use drones to help the client improve water quality in the Laurel Hollow Subwatershed by mapping water infrastructure, detecting… Read More

MS4 Illicit Discharge Investigation Using Thermal Imaging UAVs–Mill Neck Creek

Research and Development, Village of Bayville, New York (Mill Neck Creek) On this project, Walden and Harkin Aerial used drones to help the client improve water quality in the Mill Neck Creek Subwatershed by better mapping water infrastructure, detecting and locating possible illicit discharges in stormwater systems (MS4) and identifying other areas that could be… Read More

MS4 Annual Reporting and Training

Walden conducts Municipal Separate Storm Sewer System (MS4) annual refresher training for several municipal clients, where we discuss the importance of eliminating illicit discharges and meeting the minimum control measures to protect local surface waters. The purpose of the training is to ensure that the Villages deploy trained staff to enforce the permit and MS4… Read More

MS4 Supplemental Environmental Project (SEP)

Walden implemented a Supplemental Environmental Project (SEP) to address a violation observed during USEPA’s MS4 inspection at a Highway Yard. At the time of this inspection, the Contractor installing underground storage tanks at the site discharged unfiltered turbid water into the storm drain, in violation of NPDES regulations. When USEPA notified the Town of the… Read More

MS4 Inspections and Compliance

The USEPA and NYSDEC conducted comprehensive Municipal Separate Storm Sewer System (MS4) inspections at vehicle maintenance, salt storage, petroleum, and chemical storage facilities in March 2013. In preparation for the scheduled USEPA/NYSDEC inspections, Walden completed MS4 compliance evaluations at the Town’s facilities to identify compliance issues and recommend actions to comply with MS4 requirements and… Read More

Wastewater Treatment Plant Design, Defense Facility, Suffolk County, New York 

Walden’s Principal designed a tertiary domestic wastewater treatment facility designed to handle daily sanitary wastewater flow from 4,800 employees at this defense plant.  Process equipment included a screening system, aerated flow equalization tank, extended aeration treatment tank, secondary clarifier, nitrification filters, chlorine contact chamber, subsurface leaching facilities, aerated sludge holding tank, influent pumping station, equipment… Read More

Wastewater Treatment Plant Upgrade and Repairs, Suffolk County, New York

Walden evaluated the condition of this tertiary wastewater treatment plant which discharged treated wastewater to groundwater and featured denitrification filters. The plant was in poor condition but continued to meet its State Pollutant Discharge Elimination System (SPDES) effluent permit limits. Walden prepared a detailed report along with a prioritized list of upgrade/replacement recommendations.  This list… Read More

Walden Develops a Tank Coating Renewal and Improvement Prioritization Program

Working for a mid western U.S.A Investor-Owned Utility company, Walden developed a renewal and improvement prioritization program for tank coatings.  The utility provides drinking water to over 650,000 people in 46 cities and towns. With more than 125 tanks spread throughout the separate distribution systems, and limited funds for improvements, the need for a prioritization… Read More