Tag Archives: reservoir releases

Ashokan releases fluctuating during valve repairs

NYCDEP announced that perform critical and necessary repairs on the flow control valves for the Ashokan Release Channel from July 22 through July 31. During this time, flows in the release channel and points downstream will increase and fluctuate for brief intervals. The maximum release flows anticipated will be 600 MGD (930 cfs), and the minimum release flow will be maintained at 15 MGD (23 cfs) during the entire period. NYSDEC has approved the varying flow conditions and use of an alternate release point. Release Channel operations will otherwise continue in accordance with the Interim Release Protocol. 

Anglers and recreational users are advised to check local USGS gaging stations at Lomontville or Mt Marion and be aware of rapidly changing conditions. Stream level changes of 2.0 to 2.5 feet at both Lomontville and Mount Marion are expected from current conditions. The changes propagate along the creek from upstream to downstream and approximately 18 to 30 hours to travel from the Ashokan Reservoir to Mount Marion.  

Big news for the Lower Esopus

NYSDEC and NYCDEP issued a press release announcing turbidity limits and flood protections for the Esopus Creek downstream from the Ashokan Reservoir, as follows:

DEC and DEP Announce Plan to Help Safeguard Ashokan Reservoir Water Quality and Enhance Flood Protections for Lower Esopus Creek

Revised Release Protocol Protects New York City Water Supply and Addresses Lower Esopus Community Concerns about Muddy Water

DEC Adds Lower Esopus Creek to Resilient NY Program to Aid Flood Protection Measures in High-Priority Areas

State Senator Michelle Hinchey and DEP Commissioner Aggarwala Collaborate To Deliver A New Solution To Better Protect Downstream Communities

New York State Department of Environmental Conservation (DEC) Interim Commissioner Sean Mahar and New York City Department of Environmental Protection (DEP) Commissioner Rohit T. Aggarwala, and State Senator Michelle Hinchey today announced actions to limit muddy water releases, AKA ‘turbidity,’ from the Ashokan Reservoir into the Lower Esopus Creek. In addition, DEC announced the addition of the Lower Esopus Creek to the State’s Resilient NY program that identifies strategies to reduce flooding and ice jam formations in high-priority, flood-prone watersheds throughout the state.

“The newly revised protocol for the Ashokan Reservoir is intended to balance our commitment to protecting New York City’s water supply while addressing the concerns of the residents and businesses along Lower Esopus Creek,” Interim Commissioner Mahar said. “The updated policy will minimize the impacts of turbidity in the Lower Esopus and ensure the area remains a healthy and thriving environment for public enjoyment.” 

“Today’s historic shift in the Ashokan’s operations emphasizes DEP’s commitment to working closely with all stakeholders to continue our mission of providing the highest quality drinking water possible to half the state’s population,” DEP Commissioner Aggarwala said. “DEP is dedicated to using the gold standard in science to protect and enhance the watershed while working hand in hand with stakeholders helping to improve the quality of life for all residents throughout the region. I want to thank Senator Hinchey for her advocacy, DEC Interim Commissioner Mahar for his partnership, and all local leadership throughout this community for championing this issue. I look forward to continuing our collaboration on the important work that still lies ahead.”

Under newly implemented release protocols, DEP will limit downstream releases of Ashokan Reservoir water when it appears highly turbid, or muddy brown, and expand releases from both the east and west basins rather than restricting releases to only the west basin, which is often more turbid. These actions are formalized in the newly revised Interim Release Protocol (IRP), a set of standards for DEP’s release of water from the Ashokan Reservoir to the Lower Esopus Creek through the reservoir’s release channel. 

Since the reservoir’s construction, water releases from the Ashokan have resulted in turbidity in the Lower Esopus Creek, impacting recreation and aesthetics. Based on public input and community concerns about turbidity, the revised IRP limits muddy water releases from the Ashokan unless specifically requested by DEC to support the aquatic habitat. 

After conversations with State Senator Michelle Hinchey regarding DEP’s history of turbid discharges into the lower Esopus Creek and the communities’ hopes for improvements, DEP commissioned computerized modeling scenarios to develop potential alternative reservoir operations that would limit muddy discharges.  

Senator Hinchey said, “Our Watershed Communities bear the profound responsibility of stewarding the country’s largest unfiltered water system—a duty we embrace with pride, yet one that has impacted our quality of life and created an imbalance in the well-being of our region for nearly a century. Today, in a historic collaboration with my office, DEP, DEC, Ulster County and our municipalities, we make history by delivering a new solution created specifically to protect our downstream communities from turbid releases and enhance flood resiliency against extreme weather. For decades, we’ve known this moment to be possible, that greater equity could be established to do right by our downstream communities. I thank DEP Commissioner Aggarwala for being an action-oriented partner, DEC, and local residents and advocacy groups for working with us to finally reach a mitigating solution.”

The Ashokan Reservoir supplies about 40 percent of New York City’s drinking water each day. DEP utilizes water discharges from the Release Channel to the Lower Esopus Creek as an alternative to reliance on the use of chemical treatment within the water supply, specifically the use of aluminum sulfate, during episodic turbidity events. 

Turbidity is typically caused throughout the eastern Catskills by severe weather eroding reddish clay glacial sediment within stream channels and stream banks that is ultimately transported and flows into the Ashokan Reservoir. The Ashokan Reservoir was built with two basins more than 100 years ago to help alleviate turbidity, enabling suspended particles to settle in the west basin before water passes into the east basin. 

Ulster County Executive Jen Metzger said, “Today’s announcements by the NYC Department of Environmental Protection and NYS Department of Environmental Conservation represent important steps forward in protecting the water quality of the Lower Esopus and strengthening the resilience of downstream communities to climate change and the impacts of the flooding. I have long advocated for a collaborative approach to decision-making on the management strategy for the Lower Esopus, for a better overall protocol, and for more detailed and more accurate flood studies, and I greatly welcome the significant progress announced today. I want to thank Senator Michelle Hinchey, DEC Interim Commissioner Mahar, DEP Commissioner Aggarwala, Riverkeeper, the Ashokan Reservoir Working Group, our municipal leaders and community stakeholders, and local DEP and DEC teams for all your contributions to these efforts.” 

Town of Saugerties Supervisor Fred Costello said, “It’s exciting to be part of this transformative change and I want to thank the DEP and DEC commissioners for this fresh approach to a longstanding problem and thank Senator Hinchey for her leadership on this issue. I also want to thank my neighboring municipal government colleagues past and present for their dedication to this important issue and I think this a celebratory moment for all.” 

Village of Saugerties Mayor William Murphy said, “These actions are clearly a win-win and represent a tremendous comprise benefitting all communities along the Lower Esopus Creek. It all comes from an historic cooperative effort between our communities, DEP, DEC, and Senator Hinchey showing what can be done when people work together.”

Town of Ulster Supervisor James Quigley said, “As a government leader with an extensive history working with DEP, seeing an operational change solely meant to benefit communities downstream from the Ashokan is a tremendous step forward and I commend Commissioner Aggarwala for taking this initiative and the local DEP team for their open and ongoing communications. The lower Esopus Creek is a critical and complicated component of our community and I am pleased with this operational adjustment and DEC’s new commitment to improve the creek and help alleviate flooding issues.” 

Kingston Mayor Steve Noble said, “I commend the actions NYC Department of Environmental Protection and the NYS Department of Environmental Conservation have taken today, which will help improve the water quality of the lower Esopus Creek. By limiting the amount of turbid, muddy water that would be released from the reservoir and creating a more resilient and healthier lower Esopus Creek, I consider that a significant win for all of the stakeholders. I appreciate the work that all of our partners at the state and local level have done to reach this collective decision.”

Marbletown Town Supervisor Rich Parete said, “I appreciate DEP and DEC working with Senator Hinchey and downstream communities to better regulate releases and insure that all of our concerns are addressed.  It couldn’t have been accomplished without DEP and Senator Hinchey’s leadership.  It’s been a team effort.”  

Town of Hurley Supervisor Mike Boms said, “I am very pleased that the Town of Hurley is kept in the loop when it comes to decision making with lower Esopus Creek. Since becoming supervisor I’ve found DEP to be a cooperating partner and responsive to our downstream communities’ concerns. This historic shift in operations is extraordinarily refreshing and beneficial to the Town of Hurley. Thank you, DEP.”

Riverkeeper’s Dan Shapley, Senior Director of Advocacy, Policy and Planning, said, “We’re pleased to reach this milestone to better protect the Esopus Creek, an important Hudson River tributary that has been called the ‘jewel of the Catskills.’ Riverkeeper is proud to have been part of a coalition effort that has worked for years to find solutions that will prevent excessively muddy water from damaging fish, habitat, and communities along the creek. By committing to releasing cleaner water from the Ashokan Reservoir, New York City has taken an important step toward addressing a core and longstanding concern about water quality in the Lower Esopus Creek.Riverkeeper will continue to work with our partners to ensure that water released from the reservoir is managed to promote ecological health and to mitigate flood risks. The groups, agencies, and elected representatives who have worked with the Ashokan Release Working Group toward this milestone deserve our thanks.”

Resilient NY 

DEC also announced the addition of the Lower Esopus Creek to DEC’s Resilient NY Program, with the goal to improve community resiliency to extreme weather events that result in flooding and ice jam formation. Expert consultants retained by New York State are undertaking the state-of-the-art Resilient NY studies at no cost to local municipalities. These studies give communities a blueprint or path forward to abate the worst effects of future flooding.

The Lower Esopus joins 60 other watersheds across New York State already participating in the Resilient NY Program. To date, 43 studies have been completed through Resilient NY; 10 flood studies are underway and seven additional studies will be launched later this year and early in 2025.

More information on Resilient NY is available on DEC’s website.  

About the NYC Department of Environmental Protection

DEP manages New York City’s water supply, providing more than 1 billion gallons of high-quality drinking water each day to nearly half of the State’s population, including more than 8 million in New York City and a million more throughout the Hudson Valley. The water is delivered from a watershed that extends more than 125 miles from the city, comprising 19 reservoirs and three controlled lakes. Approximately 7,000 miles of water mains, tunnels and aqueducts bring water to homes and businesses throughout the five boroughs, and 7,500 miles of sewer lines and 96 pump stations take wastewater to 14 in-city treatment plants. DEP has a robust capital program, with a planned $29 billion in investments over the next 10 years that will create up to 3,000 construction-related jobs per year.

Ashokan release returns to minimum flow

NYCDEP announced additional decreases to the flow in the Ashokan Release Channel today from 200 MGD (309 cfs) to 10 MGD (15 cfs). The decrease started at 8:00 AM today (April 25th) in a series of steps until 2:00 PM.

Ashokan Reservoir storage is at 98.7 %. The CSSO for April 25th is 98.9%. Turbidity of the water in the release channel is 3.9 NTU.

Note: on May 1, the community release minimum shifts to 10 MGD and from May 1-June 30 no CSSO is in effect in accordance with the Intermim Release Protocol (IRP). NYCDEP monitor conditions and makes adjustments to releases pursuant to the IRP.

Ashokan release decreased

NYCDEP announced that it is decreasing the flow in the Ashokan Release Channel today (April 24) from 450 MGD (696 cfs) to 200 MGD (309 cfs). Additional decreases are expected as Ashokan storage approaches the Conditional Seasonal Storage Objective (CSSO).

Ashokan Reservoir storage combined is at 99.0% today, with the west basin at 96.6% and east basin at 100.3% with a slight spill at a rate of 51 MGD (79 cfs). The CSSO for April 24 is 98.7%, and the 30-year historical average is 100%. Turbidity of the water in the release channel is 4.1 NTU.

NYC DEP will continue to monitor conditions and make additional adjustments pursuant to the Interim Release Protocol (IRP.) Note: on May 1 the community release minimum shifts to 10 MGD, and from May 1-June 30 no CSSO is in effect in accordance with the IRP.  

Ashokan release adjustment

NYCDEP announced another increase in flow from 300 MGD (557 cfs) to 450 MGD (696 cfs) in a series of steps today (April 19, 2024) in accordance with the Interim Release Protocol (IRP).  The Ashokan spill and release combined will be maintained below 1000 MGD (1547 cfs).

As of April 19th, the Ashokan Reservoir storage is at 100.8 %, today’s CSSO is 97.7 %, the turbidity of the release is 5.0 NTU, and the Catskill Aqueduct is online diverting 310 MGD for water supply.

Ashokan release increased

Today, April 18th, NYCDEP announced an increase in release flow from 200 MGD (309 cfs) to 300 MGD (557 cfs) in three steps in accordance with the Interim Release Protocol(IRP).  The Ashokan spill and release combined will be maintained below 1000 MGD (1547 cfs).

Ashokan Reservoir storage is currently at 101.0 %. Today’s Conditional Seasonal Storage Objective (CSSO) is 97.4%. The turbidity of the release is 5.4 NTU. The Catskill Aqueduct is online diverting 310 MGD for water supply. 

Ashokan Release Channel Reactivated, April 17, 2024

NYCDEP announced that the Ashokan Release Channel was reactivated today and flow will be gradually increased to 200 MGD (309 cfs).  The combined flow of the Ashokan spillway and release channel will be maintained below 1000 MGD (1547 cfs) as stipulated by the Interim Release Protocol (IRP).

Ashokan Reservoir storage is currently at 101.2 %. Today’s Conditinal Seasonal Storage Objective (CSSO) is 97.2 %. The turbidity of the release is 4.0 NTU. The Catskill Aqueduct is online diverting 310 MGD for water supply. NYCDEP will continue to monitor conditions and make additional adjustments pursuant to the IRP. 

Ashokan Release Channel Shutdown

According to NYCDEP, the Ashokan Release Channel was shutdown at around mid-day on Friday, April 12th in accordance with the Interim Release Protocol (IRP) in response to rising creek levels and the National Weather Service forecast for the Mt Marion stream gauge .

NYCDEP is monitoring the stream gauge. Also, the Ashokan Reservoir is forecasted to spill beginning tomorrow morning and continuing through the weekend. The release channel will be re-activated once the streamflow and spill stabilizes. According to the IRP, operations can commence once Mt Marion falls below action stage so long as the combined spill and release flow rate remains below the 1000 MGD.   

As of April 12th, the Ashokan Reservoir storage was at 99.2% and the Combined Seasonal Storage Objective was at 96.0%. The turbidity of the release at shutdown was 2.2 NTU. The Catskill Aqueduct remains online diverting 400 MGD for water supply. 

Ashokan Release Adjustments

NYCDEP reported closure of the Ashokan Release Channel for a 10-hour period on Sunday, March 24th from around midnight to 10:00 AM, prompted by the Esopus Creek at Mt. Marion stream gage exceeding the “Action Stage” of 18ft. Afterwards, the Ashokan Release Channel was gradually reactivated to a flow of 440 MGD (681 CFS). As of Monday, March 25th, the release turbidity is 2.7 NTU, Ashokan Reservoir storage is at 98.3%, above the Conditional Seasonal Storage Objective (CSSO) of 92.3%. The Catskill Aqueduct is online and diverting 375 MGD (580 CFS) for water supply. NYCDEP will continue to monitor conditions and make additional release adjustments pursuant to the Interim Release Protocol (IRP).

Ashokan Release Adjustments

The Ashokan Release Channel was shut down over the weekend in response to the rising Esopus Creek water level at the Mt Marion gauge. With the Mt Marion dropping below Action Stage, the Ashokan Release Channel was reactivated on Monday, March 11th, increasing from 0 MGD to 420 MGD in a series of steps. NYSDEP will continue to monitor conditions and make additional adjustments pursuant to the Interim Release Protocol.

As of March 11, the current release turbidity is 5.3 NTU, Ashokan Reservoir storage is 97.7%, and the Catskill Aqueduct is online diverting 310 MGD for water supply.