Why go water sampling?

It seems that many of my blog posts are not only the result of my experiences at the Charles River Watershed Association (CRWA), but also conversations with my friends about my internship at CRWA. While my first friend-inspired post resulted in five fun facts about the Charles River, this post focuses on the water sampling project that Cait, Bruce, and I will be working on throughout the summer. Our aim is to collect data that will help CRWA understand how invasive water chestnuts are affecting the river.

After trying to explain to my friend, Will, what my work entails I realized that I was doing to him exactly what I did on the blog; I wrote the what and how of water sampling with the hydrolab and that important to us are pH, conductivity, dissolved oxygen (DO), temperature, and phycocyanin levels; however, I never explained why!

Thus, here are the parameters I listed, and a little information about them:


pH scale (courtesy of Creative Commons)

pH - is a measurement of acidity or alkalinity (base). Measured on a scale of 0.0 to 14.0, neutral water is 7.0 and acid rain is around 5.6.

Changes in pH can indicate pollution from factors such as atmospheric deposition (acid rain), wastewater discharge (sewage overflows, industrial waste), and degradation of surrounding rock. Levels can also be influenced by surrounding soil and flora.

Most aquatic life has adapted to a certain level pH so levels on either extreme of the spectra are deadly for fish and other aquatic organisms. Eggs, young fish, and amphibians are especially sensitive to low pH.

pH can also affect behavior of other chemicals in the water, so changes in acidity or basicity may cause heavy metals to dissolve and become more toxic.

Recommended freshwater level for aquatic life is 6.5-9.0 (Environmental Protection Agency).

Conductivity (specific conductance) - is an estimate of the ion concentration, essentially the total dissolved solid (TDS, mainly salt). Measures the ability of water to pass an electrical current.

Conductivity gives indication to the presence of inorganic dissolved solids such as chloride, sulfate, sodium, calcium and others. It is also directly affected by the surrounding geology. Granite bedrock will lower conductivity, while limestone and clay will increase conductivity.

Changes in conductivity can indicate groundwater input or pollution from factors such as wastewater discharge (sewage overflows, industrial waste, urban runoff - especially in the winter from road salt, agricultural runoff). High water temperature results in higher conductivity, as well as dry periods and low flow conditions.

 Recommended conductivity level for aquatic life is 150 to 500 µS/cm (FOSC). 

DO requirements for aquatic life (courtesy of
Integration and Application Network, University 
of Maryland Center for Environmental Science)

Dissolved oxygen (DO) - measures the amount of oxygen dissolved in water.

DO is dependent on temperature and salinity. Colder water can hold more DO, more saline can hold less DO.

Plants and animals can not use the oxygen in water (H2O) and thus depend on the dissolved oxygen (O2) for respiration.

In the Charles River a big problem are the invasive water chestnuts. Though dissolved oxygen is produced through plant photosynthesis, large mats of water chestnut consume more oxygen than they produce and dead plant decomposition requires DO; this results in stress for native species that must compete with the invasives for resources.

Included in the chart to the left is oxygen requirement for American shad, a fish species recently restored to the Charles!

Recommended DO level for aquatic life is 5.0 mg/L or above (EPA).

Temperature - I think this is self-explanatory...

Temperature is important because aquatic life depends on temperature. Organisms are accustomed to certain temperatures and temperature has an impact on many other parameters and is affected by factors such as weather conditions and pollution.

Phycocyanin - is a blue pigment attached to photosynthetic membranes. Present in cyanobacteria and can be an indicator for cyanobacteria presence and concentration.

Cyanobacteria levels, also known as blue-green algae (but not an algae!), are important to measure because exposure can have direct human health effects. In abundance, cyanobacteria also prevents light and oxygen from penetrating the surface of the water, resulting in negative effects on other aquatic life.

Changes in cyanobacteria levels, for example, severe algae blooms, can be caused by factors such as rainstorms that bring nutrients to the river from sewer overflows, etc, by other pollution, or by warm temperatures.

During the summer, when bacteria levels are especially high, CRWA runs a daily flagging program.

Recommended cyanobacteria level to prevent adverse human health effects is 70,000 cells/mL or below (Massachussets Department of Public Health). 

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So Will, and any other readers, I hope this was informative and helps you to understand our work a little better!

Check out the CRWA water quality monitoring page  if you're interested in learning about some of the other parameters CRWA occasionally tests for such as ammonia, fecal coliform, and nitrates, and why they are so important.

Stay sunny!
- Ingrid

Water sampling with the Hydrolab

Last week Julie trained Cait, Bruce (a wonderful local volunteer), and me to use the Hydrolab. It's basically a pole that's about 4 feet long with various probes on one end and a really long cord on the other that connects to a computer to store the data we collect. It's quite a cool piece of equipment that simultaenously measures a bunch of variables we consider for water sampling; important to us are pH, conductivity, dissolved oxygen (DO), temperature, and phycocyanin levels.

Today we were scheduled to go into the field for the first time with the Hydrolab, but with Julie away at a conference, the three of us were left to our own devices. Thanks to our wonderful teamwork we successfully (we think) completed the routine prepwork of washes and calibrations in the office and were ready to tackle the river!

Bruce had selected four sampling sites along the Charles for that are accessible from the shore. After making sure we had all the necessary equipment - the probe, field notebook, and a piece we seem to have dubbed the "hole-y thing" (due to, well, the holes in the structure that allow water to pass through it when taking measurements) - we arrived at our first site: a dock on Ware's Cove.

The sun was a bit spotty, shining down some moments and hiding behind the clouds other, but luckily it didn't rain. While recalibrating the DO probe with river water we were graced by the company of some onlookers. A nearby family of swans decided to see what we were up to and swam towards us! Cait was particularly enthralled by this; check out her blog post to read more about those lovely birds!

The next site was a dock at the Charles River Canoe and Kayak (CRCK) location on Commonwealth Avenue. Though nothing particularly exciting happened here, Cait and I felt inspired and agreed return in the afternoon (in about 15 minutes to be exact) and go for a little canoeing adventure!

The third site was located at a parking lot just across the river from CRCK. The geese there made their presence well known with their odor and poop that seemed to be everywhere. Additionally we spotted a single duck and the mechanical water chestnut harvester returning from a day of work.

The last site was right along a path that I actually had walked by before, near Brandeis, where Cait and I both go to school! Since the site was located in Bruce's neighborhood a few friendly neighbors stopped by to chat and check in on the work we were doing.

Overall it was a great morning and I look forward to many more sampling days this month with Cait and Bruce!

- Ingrid

Wildlife Viewing on the Charles (In Less Professional Terms, Baby Swans are Cute)

One often thinks that he or she needs to go to Africa or Yellowstone to see “real” wildlife. While the wildlife (especially megafauna) of both locations is spectacular, one can also see nature and wildlife here, in the greater Boston area. 

On Wednesday, Intern Ingrid, Volunteer Bruce, and I (Intern Cait) went into the field to do water quality testing (for more information on water testing, see Ingrid's blog post). At our first stop, we met a family of swans, seven Cygnets and a Parent Swan. (Young swans are called cygnets or swanlings). This was not the first time I had come across this swan family. I first saw them mid-May while running on Forest Grove Road in Waltham, Ma. The swanlings, who were swimming in a line behind their parent, were very small and fuzzy. The Parent Swan seemed to be concerned with the safety of his or her children as he or she would stop every so often, turning around to make sure they were all in the line.

In June, on our water testing day, the swans were still grey, but were bigger. This time, instead of only swimming behind their parent, the Cygnets played with each other. They splashed each other and seemed to try to cut in front of their swimming siblings. Like most baby animals, they were cute. I hope to follow this swan family throughout the summer and fall, watching as the the Cygnets trade their grey feathers for adult plumage. 

Swans were not the only wildlife that we saw. There were jumping fish, ducks, geese, swanling-less swans, and squirrels. If we had stayed longer, or looked closer, we would have seen many other animals, including insects, frogs, and other amphibians. There were also many different plant species and fungi. One only need travel to his or her backyard or the Charles River to see wildlife.

While it is sometimes difficult to visit a specific type of nature (like a specific river), here is a list of local, easily-accessible nature spots that, in my opinion, are worth visiting: 

• Ponkapoag Bog in Canton (http://www.yelp.com/biz/ponkapoag-trails-canton
• The Blue Hills Reservation in Milton (http://www.mass.gov/dcr/parks/metroboston/blue.htm)  
• Walden Pond in Concord (http://www.mass.gov/dcr/parks/walden/) 
• The Boston Harbor Islands (http://www.nps.gov/boha/index.htm)
• Storer Conservation Lands in Waltham (http://www.stonehurstwaltham.org/news_events.htm#quests
• Great Meadows National Wildlife Refuge in Concord (http://www.fws.gov/northeast/greatmeadows/) 
• Cold Spring Park in Newton (http://www.newtonconservators.org/14coldspring.htm)
• The Arnold Arboretum in Boston (http://arboretum.harvard.edu/visit/directions/)
• Boston Common (http://www.cityofboston.gov/freedomtrail/bostoncommon.asp) 
• Jamaica Pond  in Jamaica Plain (http://www.yelp.com/biz/jamaica-pond-jamaica-plain) 

 Happy nature finding!
Cait