Puget Sound Nutrient Watch: Algal Blooms

Welcome to our fourth installment of “Puget Sound Nutrient Watch,” an ongoing series of blogs that will focus on the problem of excess nutrients in Puget Sound.

Noctiluca scintillans bloom at Saltwater State Park in Des Moines June 4, 2018. Photo by Laura Hermanson.

During the first week of June, Laura Hermanson from the Department of Ecology BEACH Program noticed a red algae – Noctiluca – bloom during regular weekly bacteria monitoring at Saltwater State Park in Des Moines. 

Other blooms were also recently reported to Ecology. There was one reported to us at Seattle’s Alki Beach on June 2. And staff from our marine monitoring program, Eyes Over Puget Sound, also found presence of Noctiluca blooms present at Budd Inlet, Central Basin and Whidbey Basin during their regular fly overs of Puget Sound.

So what is this tomato soup looking stuff near our shorelines? What causes it? Is it harmful? 

Is this part of a natural cycle or abnormal?

We learned in our third installment of “Puget Sound Nutrient Watch: What is the Problem with Nutrients?” that excess nutrients can cause an explosion of algae growth called algal blooms. This rapid growth of algae can starve the aquatic environment of light and dissolved oxygen, compromising its ability to support aquatic life.

What causes these spring and summer blooms?

Each spring, Puget Sound receives an influx of fresh water from melting snow fueling our rivers. This less dense fresh water flows into the Puget Sound mixes with salt water to create a warm, nutrient-rich, surface layer that supports growing plankton populations. Spring and summer in the Pacific Northwest are marked by long days, warmer temperatures, and few storms. All of these factors contribute to slow circulation of water and an increase in layering within the water, called stratification.

Extra nitrogen and other nutrients that enters Puget Sound from human and natural sources, help feed these plankton populations until their populations grow to a bloom. Eventually the plankton bloom will use all the nutrients in the surface waters, their growth will slow until they die and sink deeper and some to the ocean floor to decay.

Budd Inlet taken from an Eyes over Puget Sound flight June, 2018.

Is this harmful?

An increase in the abundance of Noctiluca is an indication of an unbalanced system, and while the plankton is not toxic itself, their presence creates a cascade of effects in the marine food web. 

Please visit the National Oceanic and Atmospheric Administration website if you are interested or have concerns about Harmful Algal Blooms or other Marine Biotoxins.

What is it?

Noctiluca is a single-celled organism, in a group called dinoflagellates, that eats smaller phytoplankton and planktonic larvae that make up the base of a healthy marine food chain. Noctiluca contains high concentrations of ammonia which make them unappetizing prey in the food chain. Studies have shown this ammonia has a negative impact on juvenile fish within the population.

An Ecology study conducted from 2011-2015 explored the conditions in the Puget Sound that led to Noctiluca blooms by affixing sensors to ferry vessels to continuously measure plankton populations between Seattle and Victoria B.C.. When large blooms of Noctiluca exist in Puget Sound, their ravenous feeding patterns lead to a boom-and-bust of the plankton populations. 

While Noctiluca are naturally occurring and blooms have been observed and recorded in Puget Sound since the 1940’s, there is growing concern that human-caused nutrient over-enrichment is increasing the intensity, changing the timing, and increasing the spatial distribution of Noctiluca blooms.

What is being done?

Eyes over Puget Sound takes to the air once a month to obtain high-resolution aerial photographs, record observations, and gather water quality data at 37 remote marine monitoring stations to track and record how weather and climate are shaping Puget Sound water quality. Their June monitoring showed Noctiluca blooms present in Budd Inlet, Central Basin and Whidbey Basin. This recording and communication of large scale influence and impacts has helped inform Ecology’s nutrient reduction work.

The Puget Sound Nutrient Reduction Project aims to use science and collaboration to develop a plan to restore and protect Puget Sound water quality from local human sources of nutrient over-enrichment which feed algae growth. The Puget Sound Nutrient Forum is a collaborative stakeholder process that is actively seeking additional community involvement. To learn more and sign up for updates regarding the Puget Sound Nutrient Forum, visit our website. 

To learn more about Noctiluca and eutrophication, read “Dead plankton leave clues to a food-web mystery” by Christopher Dunagan at the Encyclopedia of Puget Sound.

By: Samantha Russell, Water Quality Program

Ecology denies petition to begin rulemaking to establish nutrient wasteload allocations for a Puget Sound TMDL

Puget Sound

On Oct. 10, 2017, Ecology received a rule petition from Northwest Environmental Advocates for us to engage in rulemaking to place wasteload allocations in a rule for a Puget Sound nitrogen Total Maximum Daily Load (TMDL) – or official water cleanup plan.

Some important things to know to understand this petition

Washington state law (RCW 34.05.330) provides a pathway for any person to petition an agency to request the adoption, amendment, or repeal of any rule.

A wasteload allocation is a TMDL term that refers to numeric limits placed on point source discharges of pollution. Point source pollution most commonly refers to the permitted discharge of polluted water out of the end of a pipe.

Denying the petition

We denied the petition in a letter responding to Northwest Environmental Advocates on Dec. 8, 2017. We decided to deny the petition on the grounds that we are not immediately ready to develop a Puget Sound TMDL, and adopting a wasteload allocation into a rule is not necessary to implement a TMDL.

We agree with the petitioner that Puget Sound is impaired by nutrient pollution and that a TMDL may be necessary to address this impairment. However, we do not agree with NWEA's statement that we have all the data and analysis necessary to immediately and effectively develop a TMDL for nutrients in a system as complex and vast as Puget Sound. A TMDL can be a useful tool for water quality improvement, but it isn’t the only tool in our toolbox.

Using sound science to shape our actions

We began the technical work to understand the dissolved oxygen issue in South and Central Puget Sound back in 2008. That work included a water quality model for South and Central Puget Sound, however, scientists and decision-makers learned from that work that human impacts need to be evaluated on the larger scale of the Salish Sea.

This is when scientists expanded our scientific model to the Strait of Juan de Fuca and Canadian waters to develop the Salish Sea Model. A circulation and water quality model of this size and complexity takes time to build correctly. It has been through extensive peer review by other scientists and engineers to make sure it gives us accurate results. We and Pacific Northwest National Labs have worked hard to build the technical tool to grapple with and understand the nutrient issue in Puget Sound.

Working to address the nutrient problem in Puget Sound

We finished several pieces of the Salish Sea Model in 2017. These pieces improve the model’s skill and predictive power. We also spent the year communicating what we know and understand about the nutrient problem from current data analysis using the Salish Sea model.

We have scoped the issues by talking with stakeholders, scientists, and the regulated community. We are looking at nutrient management examples from around the country, and have begun building a project implementation framework to reach our water quality goals and help Puget Sound.

Tackling nutrients in 2018

As we continue technical analyses in the coming year, we will begin developing a strategy that can be implemented to address nutrients in marine water quality.

Washington state and the U.S. Environmental Protection Agency (EPA) have invested nearly a decade of time and money developing the Salish Sea Model to give us the power to answer one big question:

What impacts are humans having on dissolved oxygen and water quality in the Salish Sea?

We are now ready to apply that model to figure out what actions are needed to reduce nutrients and improve Puget Sound water quality.

Denying the petition but still addressing the problem

While we are denying this petition to put wasteload allocations from a Puget Sound Nutrient TMDL into rule, we will continue to:

• Use the Salish Sea model to determine where treatment technologies that remove nutrients will have the greatest impact on reducing nutrient inputs to Puget Sound.
• Use the Salish Sea model to determine which nutrient reductions are necessary to avoid impaired water quality.
• Evaluate where reducing nutrient inputs from the watersheds that contribute to Puget Sound are necessary.
• Continue our work to reduce non-point sources of nutrient pollution.
• Continue working with agricultural communities to reduce nutrient runoff from farms that can adversely impact shellfish harvest areas.

Our work to reduce nutrients in Puget Sound

Follow this Puget Sound Nutrient Watch blog series to stay current and learn about our work to reduce nutrients in Puget Sound.

Earlier blogs:

• Salish Sea Computer Model
• Puget Sound's Growing Nutrient Problem

Visit our website and join our email list to get up-to-date information on the nutrient problem in Puget Sound.

We want this to be a collaborative effort that brings all of the technical work that is happening on Puget Sound nutrients together. We need all hands on deck to find the best solutions for meeting water quality goals for Puget Sound.

Contact information

Dustin Bilhimer

Puget Sound Nutrient Source Reduction Project Manager

dustin.bilhimer@ecy.wa.gov

360-407-7143

Puget Sound Nutrient Watch: The Salish Sea Computer Model

Welcome to our second installment of Puget Sound Nutrient Watch, an ongoing blog series that will focus on the excess nutrient problem in Puget Sound.

In this post we will be focusing on the Salish Sea Model and how scientific computer models help us better understand the world around us.

So...what is a scientific model?

Puget Sound Model built in the 1950's at the University
of Washington School of Oceanography as a research tool
for understanding Puget Sound circulation patterns.

Many children like to play with models — like doll houses, model cars or model airplanes. These toys are simplified versions of things we find in the world around us. These models might seem like they are just amusing toys on the surface, but they actually help you learn how the world works!

Similarly, scientists also use models. Scientists often rely on developing models to establish new science. Models are ideas that scientists use to explain patterns they observe in the world.

A computer model replicates some part of the environment in a way that helps us understand and predict potential changes. This allows scientists to ask the model questions like, "If the water temperature goes up three degrees, what happens to everything else?" If you were to change something in the model, it should tell you how changing the same thing in the environment would play out in nature.

Weather forecasting — for example — relies on computer models. Models are built to explain how aspects of the real world work and consist of ideas and concepts. Scientists use models to investigate the secrets of nature!

Characteristics of scientific models

Good scientific models should be:

• Grounded in scientific principles.
• Compared to a mechanism that is well understood.
• Calibrated to actual data so we can have confidence in the outputs.
• Be able to test if hypotheses are true or false.

New models are more likely to succeed if they dovetail or merge with existing scientific models. In fact — successful models often reveal that phenomena we once thought to be isolated are really connected incidents. Modern models use high-powered computers to compute millions of calculations!

It’s important to remember that a model is not the same as the real thing; they are similar in some respects, but not in all. A model becomes more refined and complex after many, many rounds of testing. Over time, the model looks less like the original simple model, and looks more like the real environment it is simulating.

We have confidence in a model's ability to simulate real life when it produces the same results that we find in actual data. If the model can accurately represent a known condition, we can use it to predict future conditions.

Why are models needed?

The most important advantage of computer modeling is that it gives us the ability to ask “what if?” questions about complex aspects of the world we can’t easily test in reality. Often, the focus of science is too small to be observed directly, or may be inaccessible for a direct visual study. For example, we may not be able to access the center of the earth to study it, but a computer model can give us a pretty good idea of what's happening!

Tidal motion in Salish Sea Model - 72-hour animation of April 2006 conditions.
Image courtesy of Pacific Northwest National Laboratory.

New scientific discoveries depend upon scientists developing scientific models and interacting with them. Each hypothesis tested, simulation ran, and calibration made helps scientists better understand nature. After all, science is an attempt to explain our natural environment and make predictions about it.

What is the Salish Sea Model?

First of all, this model covers a huge area! The Salish Sea includes the Puget Sound, the Strait of Georgia, and the Strait of Juan de Fuca.

Our Environmental Assessment Program and staff from Pacific Northwest National Laboratory (PNNL) developed the Salish Sea water quality circulation model — called the Salish Sea Model for short — as a tool to broaden our understanding of how nutrients travel and ultimately affect water quality throughout Puget Sound.

We are using the Salish Sea Model to evaluate how current and potential future inputs of nutrients effect dissolved oxygen levels in the Salish Sea.

The Salish Sea model helps us understand questions like:

• Are human sources of nutrients in and around the Salish Sea significantly impacting water quality now? How bad might it get in the future?
• Where are the areas that are most sensitive to human impacts? When are those effects the most harmful?
• How much do we need to reduce human sources of nutrients to protect water quality in the Salish Sea?

Domain of Salish Sea Model.

We will be using the model to test the effects of short- and long-term actions to reduce anthropogenic — or human caused — sources of nutrients. We are aim to use this information to increase Puget Sound’s resilience to the effects of climate change and population growth. These model findings will help decision-makers use resources wisely and guide where additional study or action is necessary.

How have we used the model so far? Check out these publications:

• Puget Sound and the Straits Dissolved Oxygen Assessment: Impacts of Current and Future Human Nitrogen Sources and Climate Change through 2070
• Salish Sea Model: Sediment Diagenesis Module
• Salish Sea Model: Ocean Acidification Module and the Response to Regional Anthropogenic Nutrient Sources

Ask an engineer

We’ve asked one of our Salish Sea modeling engineers — Greg Pelletier — to participate in a Q&A about the Salish Sea Model, learn more from our interview!

What have we begun to learn from the Salish Sea Model?
We are starting to learn about the effect of regional anthropogenic sources of nutrients on changes in dissolved oxygen and acidification of the Salish Sea. We are finding that there are extensive areas of the Salish Sea that do not meet the water quality standards for dissolved oxygen. There are also areas where regional human-caused sources of nutrients appear to decrease dissolved oxygen to levels that do not meet the water quality standards.

How does this model help us understand ocean acidification?
The model allows us to look at how much impact is caused by regional anthropogenic sources and compared them with global sources. For example, in waters at the bottom of Puget Sound, the model predicts that the regional nutrient sources caused by humans has the highest impact when compared with estimates of combined global anthropogenic and nutrient impacts.

The model allows us to look at how much improvement would result from efforts to reduce nutrients to different levels. Also, the model allows us to look at the relationship between hypoxia (low dissolved oxygen) and acidification.

Greg Pelletier presenting at the Puget Sound Nutrient Dialogue, July 2017

How long does does it take for us to run a scenario in the model?
The model uses a very powerful “cluster” computer at Battelle’s Pacific Northwest National Laboratory. It takes a couple of days for the computer to run all of the calculations for a single year for the original version of the model, and up to three days are required for our latest expanded version of the model.

We call each model run a scenario because it represents a particular set of assumptions. For example, one scenario is the existing conditions as they are in a particular year while another scenario is what we call “reference conditions” with human sources of nutrients removed.

In addition to the computer time, it takes time to make the input files for the model scenario – and to review the input files to assure their quality, which can vary depending on the complexity of a scenario. This step alone can take multiple people and several months.

After the model run is completed, time is required to convert the model output files into visualizations such as maps or animations of the predicted water quality, interpret what they are telling us, and discuss it with project team.

What do you like most about working with models?
The best part about working with models in my job is working with all of the great people we have on our modeling team. Our modeling team from Ecology includes Anise Ahmed, Cristiana Figueroa-Kaminsky, Sheelagh McCarthy, and Teizeen Mohamedali. We also collaborate with several great people from Battelle’s Pacific Northwest National Lab. It takes a team of people to do this work.

Different people do different parts of the model analysis. For example, some people work mainly in preparing model input information, while others work more on running the model or preparing the output visualizations. The entire modeling team works together to look at and discuss the model input files and the interpret the output visualizations. It is very rewarding to find out what the model runs tell us about the relationships between nutrient loading sources and changes in water quality throughout the Salish Sea.

Another amazing thing about working with models is its ability to predict water quality in areas where we have no monitoring data. We are confident of these predictions because the model performs well to replicate observed data when we compare it to areas where we have actual water quality measurements. Sometimes the results show us where we need to collect more data.

Puget Sound, Marine Park

Our work to reduce nutrients in Puget Sound

Follow this Puget Sound Nutrient Watch blog series to stay current and learn about our work to reduce nutrients in Puget Sound.

Earlier blogs:

• Puget Sound's Growing Nutrient Problem

Visit our website and join our email list to get up-to-date information on the nutrient problem in Puget Sound. We want this to be a collaborative effort that brings all of the technical work that is happening on Puget Sound nutrients together. We need all hands on deck to find the best solutions for meeting water quality goals for Puget Sound.

By: Jenny Robertson, Ecology Environmental Specialist

Puget Sound Nutrient Watch: A new blog series

Welcome to our first installment of “Puget Sound Nutrient Watch,” an ongoing series of blogs that will focus on the excess nutrient problem in Puget Sound.

A healthy Puget Sound is an integral part of our cultural history and future. Are nutrients causing it to change?

In this post we will be going over why we care about excess nutrients and how they are affecting Puget Sound. Read on to learn about:

• Our recent Puget Sound Nutrient Dialogue that brought together scientists from across Puget Sound region to discuss the latest science on nutrients.
• Why you should care. Understand what happens to a water body that is overly rich with nutrients. 
• Two brand-new publications on nutrients in Puget Sound. These review new modules that have been added to the robust Salish Sea computer model. 
• The report on the Sediment Diagenesis Module describes how the model incorporates the dynamic interaction of nutrients within the sediment and water column. 
• The report on the Ocean Acidification Module reveals on how the new ocean acidification module can help us pinpoint areas in Puget Sound that are influenced the most by regional sources of nutrients.
• How can nutrients be bad? Impacts that excess nutrients cause to the health of the Sound.
• What to expect in this blog series.

Puget Sound Nutrient Dialogue

We would like to thank everyone that came out to the Puget Sound Nutrient Dialogue in Auburn last month, it was a great success! We had around 120 people show up ready to participate in the conversation surrounding the science of excess nutrients in Puget Sound.

Puget Sound Nutrient Dialogue participants eager to save the Sound.

If you missed out and would like to participate in future events, please sign up for email notifications through our Listserv. We welcome the opportunity to collaborate with others who value the Puget Sound and want to protect it from excess nutrients.

Presentation slides, a summary of the event, pictures, videos, and more from the Puget Sound Nutrient Dialogue will be posted on the project webpage.

Why should we care? 

Nutrients such as nitrogen, phosphorus, and organic carbon are an important part of a healthy and productive marine ecosystem. Excess nutrients, however, can be problematic for marine water quality – most often nitrogen. Just as you need nutrients to keep your body healthy, too much of anything throws the system out of balance. 

We're working to understand nutrient problems in Puget Sound
so we can keep it the beautiful natural resource that it is today. 

When it enters marine waters in excessive amounts, nitrogen causes what is called eutrophication. Eutrophication is the term for what happens when a water body becomes over-enriched with nutrients. This over-abundance of nutrients will cause dense growth of algae and plant life and the death of animal life from lack of oxygen.

Nitrogen acts like a fertilizer causing algae to grow. Too much nitrogen results in excessive algae growth, which puts the health of Puget Sound off balance. When algae die and decompose, it consumes oxygen out of the water column (especially at depth). In some shallow inlets and bays around the Sound, this will deplete oxygen to low levels which stresses fish and the other critters that live in important nearshore habitats.

Thinking about our future

Our science today tells us we have a nutrient over-enrichment problem in Puget Sound. We are in the beginning phase of a long-term project that will ultimately help us address this overabundance of nutrients. Our goal is to ensure the Puget Sound we know and love remains resilient to stresses from nutrient problems caused by our growing population and exacerbated by climate change.

Latest science – understanding the problem

Salish Sea graphic of nutrient-rich zones
from the Salish Sea Model.

One of the most important tools for understanding the effects of nutrients in Puget Sound is the Salish Sea Model. The model was developed by Pacific Northwest National Labs in collaboration with Ecology scientists and with grant funding from EPA.

This robust computer model helps us better identify human sources of nutrients that are negatively impacting the health of Puget Sound by simulating the natural environment. It models complex water circulation and water quality dynamics in all of Puget Sound, the Strait of Juan de Fuca, and the Strait of Georgia.

Our two latest publications - released July 2017 - help predict impacts that are influencing Puget Sound's health.

The Sediment Diagenesis Module added the capability to the Salish Sea Model to simulate sediment-water exchanges. This module simulates the way organic matter decomposes, which allows the model to more accurately reflect actual conditions in Puget Sound. As organic matter decays both within the water column and bottom sediment layers, nutrients are released back to the water and consume oxygen in the process.

The Ocean Acidification Module calculates the impacts of regional nutrient sources on acidification. Results from this effort indicate that human-related sources of nitrogen and organic carbon can influence Puget Sound's carbonate system balance.

Toxic algae blooms - like this one that happened at
Deception Pass - can be caused by eutrophication.

Blogging on how this issue impacts Puget Sound’s health

Throughout this series we will dive into the specific impacts caused by excessive nutrients in Puget Sound that have damaging effects on water quality.

These impacts potentially include:

• Harming nearshore habitat and benthic invertebrates
• Intensifying ocean acidification at some locations
• Facilitating the break-down of the marine food web
• Increasing the number of algae blooms

Stay tuned as upcoming blog features dig into each of these issues, highlight new reports, and share new information as it becomes available.

Tackling the Puget Sound nutrient problem

The Puget Sound Nutrient Source Reduction Project is using best available science to understand the nutrient problems in the Sound and develop a plan to reduce human impacts so that we can protect the health and resiliency of Puget Sound.

The Salish Sea Model is a state-of-the-art computer modeling tool that allows scientists, engineers, and planners to understand the complex physical, chemical, and biological patterns in circulation and water quality. We will be using the model to compare Puget Sound to marine water quality standards, understand how bad water quality will be if we continue with the status quo, and evaluate nutrient reduction options for improving and restoring the Sound to meet our water quality goals.

Visit our website and join our listserv to get up-to-date information concerning the nutrient problem in Puget Sound. You can also this full blog series by searching "Puget Sound Nutrient Watch". We want this to be a collaborative effort that brings all of the technical work that is happening on Puget Sound nutrients together. We need all hands on deck to find the best solutions for meeting water quality goals for Puget Sound.

By: Jenny Robertson, Ecology Environmental Specialist