Posts Tagged ‘Catskill Streams’

Monday’s Bankfull Flows

Posted on: December 4th, 2020 by Tim Koch

Monday November 30th, 2020 was a rainy day in the Ashokan watershed. A home rain gauge in Boiceville measured approximately 4 inches over the course of the day.

In response to the significant precipitation the Beaver Kill, Little Beaver Kill, Bushkill, and Esopus Creek at Cold Brook reached bankfull discharge. Bankfull discharge is the stream flow that completely fills the channel in a geomorphically stable stream. Any flow that exceeds bankfull will put water onto the adjacent floodplain.

Cross section of a geomorphically stable stream where the entire channel is filled during a bankfull flow.

Streams that have berms or levees, are incised, or otherwise unstable do not have such a clear relationship between bankfull discharge and channel geometry.

In the Northeast, a bankfull or greater flow happens once every 1.5 years, on average. However, “on average” means that some years see multiple bankfull events while others have none. Monday’s event was the second time in 2020 that the Little Beaver Kill has equaled or exceeded its bankfull discharge of 909 cubic feet per second (cfs).

2020 Hydrograph of the Little Beaver Kill. From USGS.

Bankfull flow events are important because over time, these flows move more sediment than any other discharge, larger or smaller. This is because bankfull flows happen regularly, every 1.5 years on average, as opposed to big floods that move a lot of sediment but are more infrequent.

Due to the geomorphic importance of bankfull discharge events, the AWSMP regularly visits stream restoration sites, culvert replacement projects, and other stream reaches following bankfull events to take photographs and monitor any changes observed in the channel.

AWSMP staff from the Ulster County Soil & Water Conservation District inspect a restoration site on Woodland Creek following a bankfull flow in November 2019. Photo by Tim Koch.

What is a Stream Feature Inventory (SFI)?

Posted on: July 7th, 2020 by Tim Koch

Hold on tight for a bit of reverse engineering:

The Ashokan Watershed Stream Management Program (AWSMP) is a collaboration between Cornell Cooperative Extension of Ulster County, the Ulster County Soil & Water Conservation District, and the New York City Department of Environmental Protection.

All of the AWSMP’s stream management activities are undertaken in coordination with a local Stakeholder Council. The Stakeholder Council uses recommendations from Stream Management Plans to guide their decision making. Management plans contain a comprehensive review of stream characteristics, data, maps, and recommended management strategies.

The large amount of data and observations required to write a management plan for a stream come from a Stream Feature Inventory (SFI). This is where the rubber meets the road, or, where the wading boots meet the stream bed.

During a SFI, AWSMP staff from the Ulster County Soil & Water Conservation District walk a stream from top to bottom, collecting data on eroding stream banks, logjams, and infrastructure. These data are then analyzed and ultimately used to write a stream management plan.

Join AWSMP Stream Educator Tim Koch as he joins the assessment crew on a SFI of the Elk Bushkill Creek in the Town of Shandaken. This SFI is part of a larger effort by AWSMP to assess multiple headwater tributaries of the Esopus Creek, including McKinley Hollow Creek and Little Peck Hollow Creek. These tributaries may be contributing excessive sediment loads to the upper Esopus  Creek in the Oliverea valley. Excess sediment supply leads to aggradation, or sediment “filling in” the stream, which can subsequently trigger bank erosion and raise flood elevations.  SFI’s of the Esopus Creek headwaters may help to locate and prioritize restoration project sites aimed at reducing the sediment supply reaching the valley.

Stay tuned in the coming months for a SFI report on the Esopus Creek Headwaters and for a new stream management plan for the Little Beaver Kill in the Town of Woodstock.


New Video on Stream Channel Stability

Posted on: May 6th, 2020 by Tim Koch

The AWSMP office might be physically closed, but our education staff have been hard at work generating online stream based content for both youth and adults.

AWSMP Educators Matt Savatgy, Brent, Gotsch, Tim Koch, and Amanda Cabanillas.

AWSMP Educators (from left to right) Matt Savatgy, Brent Gotsch, Tim Koch, and Amanda Cabanillas during a snowshoe stream walk in 2019.


AWSMP Stream Educator Tim Koch has just released a new video on stream channel stability: what it is, and why it is important to maintain and improve the stability of our rivers and streams. This 9-minute video is meant for landowners, municipal officials, conservation advisory council members, and anyone else interested in or involved in stream management.


This video can also be viewed directly from AWSMP’s YouTube Channel.

AWSMP Watershed Youth Educator Matt Savatgy and Program Assistant Amanda Cabanillas are currently producing a series of educational videos and at-home activities for students. Follow along at home as they discuss different types of rocks, assess a culvert, and investigate stream features in a channel cross-section.


Screenshot of CCE Ulster Youth Education Video Series Website

Screenshot of CCE Ulster Youth Science Education Video Series Website


The online science series can be found at the Cornell Cooperative Extension of Ulster County website and on the AWSMP website under Videos.

Check back with us in the coming weeks, especially if you are a streamside landowner or own property in the Special Flood Hazard Area as Resource Educator Brent Gotsch will be producing a series of short videos on floodplains, floodproofing, and all things flood insurance. In these upcoming videos, Brent will teach viewers how to read a flood insurance rate map (FIRM) and the workings of the National Flood Insurance Program (NFIP) among other flood related topics.

As always, our education and technical staff are available to answer any stream, floodplain, or riparian buffer related questions! Call the AWSMP office main line at (845) 688-3047 for assistance or email

National Invasive Species Awareness Week 2018 – Japanese Knotweed

Posted on: February 26th, 2018 by Leslie_Zucker

February 26th marks the beginning of National Invasive Species Awareness Week! Throughout this week, until March 2nd, we will be exploring different invasive species present within our watershed. To start off this week, we must first ask ourselves, “What is an invasive species?”. An invasive species is a species that is non-native to an ecosystem and has the potential to cause environmental harm to an area. Invasive species often out-compete native species, giving native species little chance for survival; this includes both terrestrial and aquatic plants and animals.

Japanese Knotweed within the Watershed

Japanese Knotweed within the Watershed

The first invasive species we’ll look at is Japanese Knotweed. This monster of a plant came to the U.S. as an ornamental plant in the 1800’s from Eastern Asia. Knotweed is identified by its large heart-shaped leaves, hollow bamboo-like stalks, and clusters of white or cream colored flowers. It is often found near streams or rivers and it can withstand low-light, high temperatures, drought, and poor soil quality, making this invasive resilient to many different types of environments. Knotweed can grow up to 15 feet tall, with deep rhizomes (roots) extending into the ground, making it very difficult and timely to eradicate.

Photo of Japanese Knotweed leaves & flowers courtesy of

Photo of Japanese Knotweed leaves & flowers courtesy of

Collaboration and coordination from as many people and organizations as possible is the best way to tackle Japanese Knotweed. In order to control it, one must be diligent. The Catskill Regional Invasive Species Partnership (CRISP) recommends continuous manual removal of Knotweed approximately 2-3 times each year for at least 3 years, or until it is eradicated. According to New York Invasive Species Information (NYIS), mowing or cutting of Japanese Knotweed will actually spread the plant, rather than contain it. For those who would like to use herbicides on large volumes of Knotweed, call your local CCE or Soil and Water Conservation District office to get more information on chemical regulations and safety precautions in your region.


Videos regarding Invasive Species in New York State:

Prevent the Spread of Invasive Species

Get to Know Invasive Plants


Follow us this week as we uncover more invasive species in our Ashokan Watershed! FacebookTwitterInstagram




New Interns Hit the Field

Posted on: June 20th, 2017 by Leslie_Zucker

Samantha Kahl, AWSMP’s Temporary Watershed Educator reports on training for this year’s seasonal stream technicians. The technicians, and occasionally Sam, will be in the field surveying Ashokan Reservoir streams this summer. In Sam’s words….

I just spent five days with seven Watershed Corps (WCC) interns training under the supervision of Mark Vian, Emily Polinsky, and Danyelle Davis of the NYC DEP Stream Management Program.

The first three days of the Stream Management training was conducted in a classroom at Ulster County Community College (UCCC).  Mark and Emily provided us a solid (and fun) academic background detailing watershed history, the importance of stream monitoring, and various tools and techniques used in the field. They are fountains of information regarding the NYC Watershed, making the academic portion both interesting and exciting.

WCCC Training 2017_Credit Emily Polinsky

From Left to Right: Justin Alecca (Brown hat, purple shirt), Samantha Kahl, Brendan Keating, Aaron DePetris, Amanda Cabanillas (crew leader), Bridget Bromm (UCCC), Erica DePalma (SCA), Mark Vian, Travis Ferry (RNSMP), Courtney Brill, Emily Polinsky, Aimee Hartwig, Winston Gedicks.

Due to inclement weather, we lost one of our field training days, but our fearless leaders made the most of our remaining two days out in the field. We traveled to the Frost Valley YMCA where we accessed the West Branch of the Neversink River for our second round of training. Mark, Emily, and Danyelle, as well as seasoned WCC intern Amanda Cabanillas, reinforced our academic education by getting us in the stream for visual assessments and conducting stream cross-sections using laser levels and stadia rods. We also trained on specific computer software (RiverMorph) that produces a graph of the cross-section data collected; the software provides a visual representation of how the streambed looks if you were to cut the stream in half.

Provisional Data XS1 FVMF

A stream channel cross-section.

The entire group is comprised of intelligent and dedicated students from all backgrounds; each of them contributing to the training in their own amazing way. A friend from the Roundout Neversink Stream Program shared with us the benefits of Chaga mushrooms and where to find them; a UCCC student shared his fly tying stories with us; while others shared experiences from their lives and their reasons for entering the environmental field. It was great to be in the field and work with students and professionals learning about geomorphology, all of whom respected each other and genuinely cared about stream management practices. In my opinion, we all came out of the training with the knowledge and field experience necessary to be successful in our desired fields.

Stream Research: Learning the science of streams

Posted on: June 4th, 2015 by Leslie_Zucker

I spent the last two days standing in a stream. Was it cold? Yes. Was I fishing? Nope.  Instead of wading into the cold mountain waters (in waders, don’t worry!) of a pristine Catskill stream to fish, I was learning stream science and collecting data. Scientists from NYC DEP are beginning their field research season, and with the help of interns from a SUNY Ulster internship program, they are conducting hands-on field research to measure, monitor, and protect streams in the Catskills. With a clipboard in hand for recording data, I observed my coworkers teaching, orchestrating field equipment, and demonstrating hands-on survey procedures of stream assessment. We were learning how to measure the features of the stream to determine its erosion potential and impacts to water quality, which involves collecting a substantial amount of data. We carefully arranged field equipment along the length and width of the stream, and measured details about the stream channel’s dimensions and structure, including riffles and pools, slope, channel depth, floodplain, and looked for evidence of how the stream changes over time, and why.


West Branch Neversink River

West Branch Neversink River

Most people don’t realize how much is actually happening in a stream ecosystem. Streams are absolutely buzzing with the life of flora and fauna, and they are also in constant motion, trying to reach energy equilibrium. The old adage that “You never step in the same river twice”, rings true as streams are constantly changing and adjusting their sediment materials, plant materials, water flow and channel path.

Caddisfly Larvae Casings on a Rock in the Neversink River

Caddisfly Larvae Casings on a Rock in the Neversink River

As an educator, I tend to look at stream ecosystems as a whole system of many parts, much like a puzzle that makes up a whole picture. I want to explore how the ecosystem works and why we conduct research to help others understand the use and importance of this work. The research and training we conduct helps managers better understand stream channel structures, stability and potential for erosion that may impact human infrastructure, and water quality down river. Stream research also helps scientists and engineers to recognize how healthy and stable streams work so that they can utilize that information and data to stabilize and restore streams with structure and erosion problems in other places.

Neversink River - Cross Section Survey

Neversink River – Cross Section Survey

Everything we do in and around streams has an impact on them. For this reason, we strive to understand how they work and change so that we can reduce negative impacts when our lives and work, and their movement converge. Wading across the rocks of a rushing stream while trying to take measurements for stream data can teach a person a lot of respect for the power of moving water.  Trees that fall into the stream also impact its structure, flow, stability, and provide critically important habitat for aquatic life such as fish and insects. The stream I was standing in wasn’t very wide, but its geomorphic structure was incredible with a wall of bedrock on one side of the stream, and a mound of small rocks on the other side. It was a stunning place to spend a couple days learning and collecting data that will be useful for research and restoration projects in the future.

Neversink River - Bedrock wall

Neversink River – Bedrock wall