Consultants Provide Analysis of Village's 100 Year-Old Water Distribution System: Rob Cole to Serve as Interim Village Manager

How does Scarsdale address and manage its aging infrastructure? How does the town decide which improvements to make and how to keep up with the demands of residents?

These are among the questions the Board of Trustees sought to answer when it commissioned the firm Woodard & Curran to create a Water Demand Study and examine the needs of the village’s water infrastructure system.

After reviewing 12 applications and interviewing five firms, the Board decided in September 2020 that Woodard & Curran was the most suitable choice to conduct this analysis. During the Board’s Work Session on Tuesday, May 26, 2021, three representatives from Woodard & Curran presented their draft report to the community.

The Scarsdale water system consists of 98 miles of pipe, two pumping stations, and two water tanks. The focus of the report was the water distribution system. The firm compiled and digitized existing maps, created an updated system map, reviewed the system’s maintenance history, developed a new hydraulic model, and created a capital plan for the water distribution system.

To update the current mapping system, the firm reviewed over 500 paper maps, sketches, and notes and updated historic mapping information. They used this new mapping as the foundation for the hydraulic model. Using the model, they simulated and analyzed the flow of water through the system, evaluated fire flow availability, and gauged how the system responds to issues. The model accounts for friction from areas of older pipes and factors in where water is used most frequently.

The standard recommended system pressure is 35 pounds per square inch (PSI), and Scarsdale’s system achieves this figure except for a few spots in higher elevation areas. Pipe velocity was up to code throughout the system, and water pressure loss was worst in areas with unlined cast-iron pipes. In terms of fire protection, most of the system has greater than 1000 gallons per minute of protection, with a few higher elevation areas having less than 500.

When reviewing the system’s maintenance history, the firm found several issue areas that consisted of older and unlined pipes. There were around 200 water main breaks and pipe failures between 2008-2020, which the representatives identified as a high number of issues, but said the figure was not unexpected.

In developing an improvement plan, Woodard & Curran prioritized the areas of highest maintenance needs and ranked remaining pipe segments on the likelihood and consequences of failure. In total, 76 pipe rehabilitation projects were identified for an estimated total of $103 million. The firm identified the top three priority projects:
1. Crossway: A section of unlined universal joint segment that is corroded. The proposed solution is the replacement of three-quarters of a mile of pipe along Crossway.
2. Garden Road / Mamaroneck Road: This is one of the areas of lowest pressure and lower fire flow availability. The proposed solution is a combination of lining and replacement for two miles of piping.
3. Griffin Avenue: Another area of concern that the firm suggests focusing on.

Woodard & Curran and now in the phase of conducting a Rate Study to review the current rate structure and revenue. This study will include a cost-of-service assessment, a revenue and benchmarking assessment, and a rate model development and review. The firm’s presentation also included information and resources for various government grants and funding sources that could be potential sources of revenue for the project.

After the presentation, Board members and staff had a chance to ask the representatives questions about the report and make suggestions for future work. Trustee Crandall inquired about putting some of the electric and cable lines underground while this construction work is happening to make the village more storm resilient. In a similar vein, Deputy Village Manager Rob Cole asked if it would be possible to tie in a high-capacity data line into Post Road and bring it to the Village Center to support business development. The representatives noted that different types of projects can be joined together while the pipes are already being worked on, and these are all considerations the Board will want to consider while making project decisions.Robert Cole will serve as Interim Village Manager

Ms. Crandall also asked about the issues the town of Greenburgh had when they replaced their pipes, and if the firm has done any studies on the toxicity of these pipes. The firm responded that Greenburgh’s issue was not related to toxicity but instead had to do with conventional cement lining, which will not be an issue for Scarsdale if they choose a more modern construction material.

Trustee Ahuja asked when the firm was choosing the projects for the water system, how much of the decision was based on subjective judgment versus scientific fact. The representative replied that there is a need for both when designing a plan. Engineers must evaluate where the areas of concern are based on their experience and look where the data on past pipe maintenance supports project work. He added that to develop a sensible project, subjective judgment must be applied to frame the construction in the most cost-efficient manner and to cluster groups of pipes together based on similarities and economic feasibility.

Mayor Veron, as well as other trustees, also spoke about the sustainability practices that could potentially be incorporated into the project. Village Manager Papalardo added that once funding is secured, it will be unlikely the village can accomplish more than one project every two years. He added that coordinating between the water department and the sewage department could make the whole project more effective. The Board eagerly awaits the results from Woodard & Curran’s Rate Study and looks forward to the next phase of this massive infrastructure project.

Village Manager

At the Village Board meeting following the work session, Mayor Jane Veron announced that Village Manager Steve Pappalardo will leave on July 9, 2021 and that 54 applications were received for the position.  The Board plans to interview some of these candidates throughout the summer. In the interim, Deputy Village Manager Rob Cole will become Interim Village Manager of Scarsdale. He has served here for six year and worked in Oak Park, Illinois for 19 years.