USA Volunteer Water Monitoring Network

Nutrient Monitoring


Question 1: I’m looking for information on how groups are monitoring for nutrients.  Do spectrophotometers such as LaMotte or Hach get results comparable to a laboratory?

Question 2: Could anyone provide me with some information on ammonia monitoring?

Question 3: Do you know of nitrogen-focused fact sheets that are available online?

Question 4: I am requesting feedback from groups that have used nitrogen testing kits or probes.

Question 5: I’m wondering what methods you use in your programs to assess phosphorus?

Question 1

Date: Fri, 07 Nov 2008 10:53:52 -0500
From: Angel Dybas
Subject: Question regarding nutrient monitoring
To: Kris Stepenuck
Organization: Cornell Cooperative Extension

Hi Kris,

I tried to send out an email to the listserv last week, but I don’t know if it went through. I’m looking for information on how groups are monitoring for nutrients. I may be taking over a water quality monitoring program that we have at Cornell Cooperative. In the past, they monitored nutrients four times a year using the LaMotte spectrophotometer that we have. Since nutrients are a huge problem in the estuary we’re monitoring, I would like to monitor for nutrients more often, however, the spectrophotometer that we have is not giving accurate readings. I would like to know if spectrophotometers such as LaMotte or Hach are capable of getting results comparable to a laboratory. If you know of anyone that could provide some advice, it would be greatly appreciated.



Responses to Question 1

Date: Fri, 07 Nov 2008 13:28:37 -0600
From: “Clay, David”
Subject: RE: [CSREESVolMon] Question regarding nutrient monitoring
To: Kris Stepenuck

My suggestion is to send you instrument in for recalibration and run appropriate standards.

David Clay, Director
Drought Center
Brookings, SD 57007


Date: Fri, 07 Nov 2008 11:54:49 -0800
From: Bridget Hoover
Subject: RE: [CSREESVolMon] Question regarding nutrient monitoring

Hi Angel, most of our nutrient analysis is conducted by a certified lab, however, for a couple of programs we do use Hanna meters in the field for orthophosphate and ammonia. Both have shown good correlation with lab samples (with slight modifications to the manufacturer’s instruction and reagents). If you’d like more details I can provide them.

Bridget Hoover
Water Quality Protection Program Director
Monterey Bay National Marine Sanctuary
299 Foam Street
Monterey, CA 93940
B (831) 647-4217
F (831) 647-4250


Date: Mon, 10 Nov 2008 10:01:24 -0600
From: Jay Gilbertson
Subject: Nutrient monitoring question

Angel: Through the wonders of listserv, your question about nutrient monitoring made it to South Dakota. For several years now, we have been using a couple of HACH sprectophotometers (DR/4000 and DR/5000) to test for nitrate in well water and other samples. The particular test we use is one that does not require any additional sample manipulation, so it lends itself well to public outreach ( When we have checked our machine results against those from splits sent to our State Health laboratory, the results have been very good (for the both the project summarized at the website, and all subsequent tests). So far, we have really only had one sample exhibit a large deviation, and that is attributed to operator error (I had loaned the device out to a local soil conservation district, and they appear to have screwed up the math).

We have not tried measuring any other constituent, but I am reasonably confident that the results would be the same. We have been very satisfied with our HACH units (although at >$6,500 each, I would hope they work well!).

Jay P. Gilbertson, Manager
East Dakota Water Development District
132B Airport Avenue Brookings, South Dakota 57006
(605) 688-6741


Date: Tue, 11 Nov 2008 09:02:54 -0500
From: Todd Walter
Subject: Re: [Fwd: [CSREESVolMon] Question regarding nutrient monitoring]
To: Angel Dybas , “Brian K. Richards” ,
Larry Geohring

Hello Angel,

Your question about monitoring nutrients was forwarded to me (among others). We do quite a bit of nutrient monitoring and might be able to help answer your questions. First, what is the objective of your monitoring (what do you want to see) and what nutrients are you interested in? Also, what are typical nutrient concentrations?

In general, you can get very good results with a wide range of approaches if the person doing the analysis is careful. The community science institute here in Tompkins County has one spectrophotometer and some burettes that make up the core of its analysis equipment and they generally get reliable numbers.



Date: Sun, 16 Nov 2008 13:05:29 -0800 (PST)
From: Paul Mack
Subject: Re: [CSREESVolMon] Question regarding nutrient monitoring


Here are my 2 cents…

Hach spectrophotometers are respected and widely used in industry. We have had good reliability with our old Hach instrument in nutrient analysis, and it still can calibrate to standard solutions with an accuracy of 1%. Accuracy isn’t so much a factor of the device itself rather than the skill of the operator using it. In good hands it will give results that are within the ballpark of a professional lab; in sloppy hands, it is useless. So, we try to use volunteers with job experience or education in science/engineering.

Professional laboratories are not always a gold standard by which you should compare your results: we once tried a side-by-side test with a local professional lab, but their results were so bad that we could draw no conclusion and it was a waste of money. That said, even two professional labs testing the exact same water sample will arrive at two slightly different results.

In your email, you question the validity of your test results and mention “nutrients are a huge problem in the estuary we’re monitoring”. If you mean that the nutrient concentration is known to be severe (such as in excess of 5 mg/L) in the estuary, then you must dilute the water sample prior to testing, and then multiply the spectrophotometer reading by the same factor to arrive at the final value. The amount of dilution is dependent on the estuary’s nutrient concentration as well as your spectrophotometer’s test range. Your spectrophotometer’s manual specifies a different working range for each analyte; for example, it might specify “Range: 0 – 4.5 mg/L” for nitrate. If your estuary’s actual nitrate concentration is 21 mg/L, then you would dilute the sample by 5x to bring it down to the spectrophotometer’s range. Then, you would multiply the spectrophotometer reading by 5 to arrive at the final value.

Dilution should be done with laboratory-grade deionized/distilled water.

Paul Mack
Sierra Club – DuPage County, Illinois

Question 2

From: Brian Soenen []
Sent: Monday, July 11, 2005 3:14 PM
To: Volunteer water monitoring
Subject: [volmonitor] Volunteer Programs and Ammonia Monitoring

Greetings from Iowa!

I am wondering if anyone could provide me with some information on ammonia monitoring. We’d really like to improve the IOWATER program by adding ammonia as a parameter, but would first like to find a monitoring kit that satisfies a couple requirements:

1) Field kits – Any kit we choose to adopt must be a field kit – i.e., results are obtained in the field at the monitoring site. Most of our current kits for our other parameters use test strips and/or color
2) Ease of use – The easier to use the better
3) Reliable data – When dealing with easy-to-use field kits, data quality is sometimes compromised. We conduct side-by-side monitoring with all of our kits and professional methods to ensure data quality, but it would be nice to know which kits not to spend our money/time on.
4) Non-hazardous wastes – We are not interested in kits that yield heavy metals and/or pose any other disposal or health issues.
5) Inexpensive – The cheaper the better

Any ideas/suggestions you can send will be greatly appreciated.

Brian Soenen
IOWATER Coordinator
3625 Nebraska Street
Sioux City, IA 51104
515.205.8587 (cell)

Responses to Question 2

>>> “Chris Sullivan”
7/11/2005 2:30 PM

Hi Brian,

How are you doing? For Project SEARCH we utilize Lamotte Colorimetric analysis using the Nesslerization method, but this does generate mercury waste, so dont try that one.
I also coordinate a volunteer program in my spare time that uses Hach Pocket Colorimeter for ammonia anlaysis. The colorimeter is electronic so costs are higher but more reliable and precise than the color wheel option offered by Hach.

Here is a link to the product we use.

like I said it is a little pricey, but my volunteers (mostly retired folk or high school students) have no problems using the equipment or reagents. I am pretty sure there is no mercury generated in this process either, so that is beneficial for you as well.

Good luck with your quest!!


Chris Sullivan
Project SEARCH Coordinator
(203) 734-2513
FAX 203-922-7833
Center for Environmental Research Education
Kellogg Environmental Center
500 Hawthorne Ave
Derby, CT 06418

>>> Kris Stepenuck 7/11/2005 3:01 PM >>>
Hi Brian-

For rough scale stuff, we have the volunteers use the Hach test strips. We
expect them to find no ammonia based on specificity of the test strips, and
if they do find some positive result, then we follow up with a grab sample
that gets shipped to a lab. Here is the catalog number for the strips we use: Test Kit, Ammonia
Test Strips, 0-6 ppm, 25 tests Cat# 2755325


>>> Phil Emmling
7/11/2005 3:32 PM >>>

I will look at my kits for ammonia. I made analytical standards and tried 3 or 4 kits. The best kit I found was a cheap cube from either Hach or LaMotte. The test uses salicylate. The kit was the least toxic, needed the least time for color development (1 minute), and seemed to be able to tell normal (~0.050ppm) from problem (>1.000) concentrations. I did not like the color wheels or comparators. I had a problem using the same glassware for nitrate-nitrite for ammonia in a color comparator because the nitrate test converted N03 to ammonia and was higher 1-10ppm than the usual ammonia range of 0.025-0.100. I actually used 50% sulfuric acid to rinse the plastic tubes and later used glass tubes. The basic reagents in the Cd reduction N03 test stuck to the plastic tubes more than the glass.

You should buy a kit and try to make it work with analytical standards or ammonia added to real samples having ammonia to see if you can make it work before turning it over to volunteers. Chemetrics has a low and a high range test. The low does increments of 0-1.0 and the high does
0-10. I would bet that the 0-1.0 tests are hard to distinguish and reproduce but most samples will be less than 1.0. It would be good to do pH on the samples since NH3 is toxic to fish and NH4 is not toxic
but both will be analyzed with any test. At pH 9.3 1/2 will be in each form. At higher pH NH3 will dominate and at lower pH (most of the time)NH4 will dominate. The range around the 50% each mark of 9.3 (isoelectic point)is about 1 pH unit. At pH 10.3 about 100% will be NH3 and lower than 8.3 100% will be NH4. There are tables for estimating each form if you know the pH.

I will get back to you tomorrow with the kits I played with.

Phil Emmling
Environmental Chemistry & Technology Program
660 N. Park St.
Madison, WI 53706
Phone: 608 262-2899
FAX: 608 262-0454

>>> “Petersen, Gordon”
7/12/2005 5:44 PM >>>

Mr.. Soenen,
Your message was forwarded to me. My name is Gordon Petersen and I am with the Hach Company and I am located in central Iowa.

I would recommend salicylate chemistry with a color disc wheel or Pocket Colorimeter II. The color disc wheel is catalog #24287-00 and measures up to 2.5 mg/L. The PC II is 58700-40. You will probably prefer the color disc wheel because of the price and non-hazardous chemicals.

Let us know if you have further questions. You can contact sales or tech support at 800-227-4224 or leave me a message at ext. 2112.

>>> Phil Emmling
7/27/2005 8:35 AM >>>

OK. I ordered several kits and settled on 2 but I honestly can’t remember why. The standard is made for 1 mg/L N. It might be useful to remember that pH determines the % that is likely to be NH3 versus NH4.
There are tables with the values. The 50% point is pH 9.3 and generally 1 pH unit either side determines whether 100% is one form or the other. At pH 10.3 100% should be in the toxic to fish NH3 species while at pH 8.3 100% should be in the NH4 form. Since most streams are between 7.5-8.9 a lot is NH4. I don’t know what the situation is for an anhydrous ammonia spill or liquid manure slug. I assume these are undiluted plumes that can be toxic and the pH is probably alkaline.

Phil Emmling
Environmental Chemistry & Technology Program
660 N. Park St.
Madison, WI 53706
Phone: 608 262-2899
FAX: 608 262-0454

>>> Phil Emmling
7/27/2005 8:58 AM >>>


Here is a Website that I found for testing aquarium water The hobby people can be a good source of information about water chemistry that can be useful to citizens.
This looks like the cube that I have at home. I don’t see any mention of carryover from test to test. There is a link to a table for pH and temperature considerations and mention of 0.6ppm total ammonia being
toxic to aquarium fish. The ammonia standard of 1 mg/L N is equivalent to 1.22mg/L as NH3 if all the N in the test is NH3. There is a nice example at the bottom of the table for calculating NH3 at pH 7 and 18C at a total ammonia concentration of 0.8 mg/L.

Phil Emmling
Environmental Chemistry & Technology Program
660 N. Park St.
Madison, WI 53706
Phone: 608 262-2899
FAX: 608 262-0454

>>> Phil Emmling
7/27/2005 9:15 AM >>>


I used the table to make a calculation of toxic NH3. If we measure 0.8mg/L with a kit at pH 8.3 and 20C (conditions in a lot of stream for pH and T) the factor is 0.0736 from the table. 0.8mg/L x 0.0736 is
0.058mg/L N as NH3. If we subtract 0.058 from the total measured N of 0.08 we have 0.742 mg/L N as NH4. I calculate 92.6% N as NH4 and 7.4% N as NH3. I think we need to take the 0.058mg/L N as NH3 and convert it to NH3 by multiplying by 1.22 or 0.058 x 1.22= 0.07 mg/L NH3. I made my standard according to the directions given in Standard Methods and the conversion of 1mg/L N to 1.22 mg/L for NH3 comes from Standard Methods. The aquarium article does not give a toxicity value for NH3.

Phil Emmling
Environmental Chemistry & Technology Program
660 N. Park St.
Madison, WI 53706
Phone: 608 262-2899
FAX: 608 262-0454

>>> Phil Emmling
7/28/2005 8:48 AM >>>

Last night and this morning I tried my 2 kits with newly made standards. I made a 1000ppm N-Nh4 and diluted to 100ppm. I used the 100ppm to make 0.5, 1.0, and 2.0 for LaMotte kit code 3304. I used the same 100ppm standard to make 0.8 and 0.4 ppm for the low range Hach kit cube #22669.
I made the dilute standards fresh from the 100ppm for each evening and morning tests.

Both sets of standards gave the same but confusing results. The LaMotte kit has a color matching Octa slide #1100 and the standards all looked about 1/4 of the anticipated values. Thus the 2.0, 1.0, and 0.5ppm standards looked like 0.5, 0.25, and >0.1 or about 0.125. I repeated the tests this morning because I thought the standards were made incorrectly. I don’t think the 1000ppm was wrong and 100ppm is a no brainer from 1000ppm. The Hach cube read high instead of low. The 0.8ppm and 0.4ppm standards read about 1.0 and 0.6ppm respectively. All standards were made from the same 100ppm stock.

I called LaMotte to ask whether my LaMotte reagents are too old. I need to order new reagents because 2 of 3 are past recommended shelf time (1 and 1 1/2 years). The lots were made early in 2003. The low range Hach cube(0,.2,.4,.6,.8) seems OK. The LaMotte kit reagent 1 is sodium hydroxide and this is hard to rinse so I am still rinsing with 50% sulfuric acid. I might try vinegar as a less dangerous rinse. It
seems particularly important not to use nitrate test glassware for the ammonia test. The 5-10ppm nitrate levels are converted to ammonia and the base reagent increases carryover to the lower level ammonia test.

The Lamotte 3304 has ranges 0,.05, .1, .25, .5, 1, and 2ppm. I don’t think the 0, .05, or .1 are easy to distinguish from each other. Most of the samples I had run at UW Stevens Point lab for ammonia/ammonium from Castle Rock Creek in SW WI ranged around .03-.05ppm at base flow.
This creek is similar to NW Iowa springcreeks in dairy cow areas. I think you can tell .1, .25, .5, 1, and 2ppms apart using the Octa slide. I need to order new reagents and try again. After I get the standards
to work, I would like to do a standard addition experiment using creek water. Both kits use Salicylate reagents.

I think you could try these 2 kits.

Phil Emmling
Environmental Chemistry & Technology Program
660 N. Park St.
Madison, WI 53706
Phone: 608 262-2899
FAX: 608 262-0454

>>> Phil Emmling
8/9/2005 2:34 PM >>>

I received fresh reagents from LaMotte and it made a big difference. The replacement 3 reagents cost $25.50. I think you have the kit number. It is difficult to match the color with the Octet reader but if
it is darker than 0.025 and lighter than 1.00, it could be reported as 0.050 or the color in the middle. I won’t have time this week to play with it using standard additions. The test takes about 25 minutes.
It will distinguish <0.50 from 1 and 2ppm. Perhaps it works best as a red flag than a test for spatial or temporal trend analysis. I used vinegar instead of 50% sulfuric acid to clean the glassware and it seemed to work OK. I would suggest having the Iowa DNR lab play with the ammonia test. If you decide on a test I would like to know which one worked. I would rate this test about as good as the standard N-nitrite/nitrate test.

Phil Emmling
Environmental Chemistry & Technology Program
660 N. Park St.
Madison, WI 53706
Phone: 608 262-2899
FAX: 608 262-0454

>>> “Linda Green”
8/17/2005 2:00 PM >>>
Hi Brian,
Here at URI Watershed Watch we have our own analytical lab and use an Astoria-Pacific segmented continuous flow nutrient autoanalyzer for our nutrient analyses, since our waters are typically
<2ppm in any form of nitrogen, which I think is pushing the limit on kits. I was fortunate that our Dean contributed ~ 75% of the $42K it cost to purchase the autoanalyzer last year, it was replacing a 15 year old model that had been purchased by a professor I worked with. The prof departed a number of
years ago without the analyzer, I took it over. My background is in soils and chemistry and I already was a lab tech when I started Watershed Watch so I was fortunate to have good lab access, and also great support from URI and my college. Analyzing ammonium-N was pain with the old autoanlayzer, much
better with the new one, my detection limit is ~ 20 ppb, 0.020 ppm as N. Elizabeth Herron shared with me your reply about top 3 choices for NWQ 06 vol mon workshops. We really appreciate your enthusiastic response!

URI Cooperative Extension Water Quality
Department of Natural Resources Science
1 Greenhouse Road
Kingston, RI 02881-0804

Question 3

Date: Tue, 12 Jun 2007 16:44:13 -0500
From: Kris Stepenuck
Subject: [CSREESVolMon] Nitrogen (and other) publications sought

Hi everyone-

Do you know of nitrogen-focused fact sheets that are available online? We’ve been approached by a volunteer monitoring coordinator looking for information about nitrogen (as related to water quality, but
also in general) and would like to add listing of these publications to a section of our website that lists volunteer-monitoring related publications ( Any suggestions of nitrogen-related informational fact sheets would be appreciated!

Also, if anyone else has ideas for publications they’d like to have listed in clearinghouse format (like we plan to do with the nitrogen ones), please let me know what topics you’re interested in having available at the website.

Kris Stepenuck, on behalf of the Volunteer Water Quality Monitoring
National Facilitation Project

Wisconsin Volunteer Stream Monitoring Program Coordinator
445 Henry Mall, Rm 202
Madison, WI 53706-1577
Phone: 608-265-3887
Fax: 608-262-2031

Responses to Question 3

Date: Tue, 12 Jun 2007 14:55:42 -0700
From: “Snouwaert, Elaine (ECY)”

The Washington Department of Ecology has this general focus sheet on
nutrients available:


Date: Tue, 12 Jun 2007 21:47:20 -0700
From: Erick Burres


Fact sheets can be found at

3.3. Nutrients
3.3.1. Ammonia Ammonia Fact Sheet [English] [Spanish] Ammonia Salicylate Kits (SOP)
3.3.2. Oxidized Nitrogen – Nitrate (NO3) and Nitrite (NO2) Measuring Nitrate and Nitrite (SOP)


Erick Burres
Citizen Monitoring Coordinator
SWRCB- Clean Water Team

You can self-subscribe to the Clean Water Team’s E-Mailing List. To subscribe go online to our website and check the box marked Citizen Monitoring Program/Clean Water Team.


Date: Wed, 13 Jun 2007 14:38:09 -0400
From: Tony Williams
Subject: RE: [volmonitor] Nitrogen (and other) publications sought
We monitor nitrogen…

and scroll down to our watershed protection publications…


Date: Tue, 12 Jun 2007 15:05:44 -0700
From: Sandy Lyon
Subject: RE: [CSREESVolMon] Nitrogen (and other) publications sought

Hello Kris,
I have been doing some nitrate assays in our water quality monitoring program in the Umpqua Basin in Oregon. I have been very happy with an enzymatic assay produced by the Nitrate Elimination Co., Inc. (NECi) which produces an assay with no toxic components; it can just be flushed when you are done. Their website ( information about the assay as well as a section at the bottom of their homepage called “Useful Information”. This provides links that may be of interest.
Sandy Lyon
Monitoring Coordinator
Partnership for the Umpqua Rivers
1758 N.E. Airport Road
Roseburg, OR 97470
(541) 673-5756


Date: Wed, 13 Jun 2007 09:08:53 -0500
From: “Broz, Robert R.”
Subject: RE: [CSREESVolMon] Nitrogen (and other) publications sought


Several years back we produced a series of Water Quality guides and some of the first were on nitrogen. They can be found at the University of Missouri website: and go to the google search of the site. The guides are

WQ252 Nitrogen Cycle
WQ253 Nitrogen’s Most Common Forms
WQ254 Nitrifcation
WQ255 Denitrification
WQ256 How Nitrogen Enters Groundwater
WQ257 Ammonia Volatilization
WQ258 Nitrate Poisoning
WQ259 Nitrogen in the Plant
WQ260 Mineralization – Immobilization
WQ261 Nitrogen Fixation

There are a couple more but these will give a pretty good overview of
nitrogen basics, and then how it enters the environment. I don’t have
anything in this series that focuses on surface water.

Good luck and I hope this helps.


Bob Broz
University of Missouri
205 Agricultural Engineering
Columbia, MO 65211
(573) 882-0085


Date: Wed, 13 Jun 2007 10:34:28 -0400
From: Ailene
Subject: Re: [CSREESVolMon] Nitrogen (and other) publications sought
This is such helpful information.  The only resources that I use regularly for comparison and clarification are:

Standard Methods for the Examination of Water and Waste Water ( which has nitrogen information) and LaMotte information on Colorimeter and Spectrophotometer testing for various forms of nitrogen.
I can give you better reference information on these if that would be helpful.

(Go to http://www.; click onto Kit Instructions; Move down to the manuals for 1200 Colorimeter and Smart Spectrospectrophotometer. Click on one of these and then click on to Individual Test Instructions.  Go to the nitrogens including ammonia , nitrite, etc).
Thanks you for sending your bibliography.  I know I will use it.

Ailene K. Rogers

Marine Program Educator for Water Logging
Cornell University Cooperative Extension of Suffolk County
180 Little Neck Road
Centerport, NY 11721

Tel: 631-854-5544 x22
Fax: 631-854-5543


Date: Wed, 13 Jun 2007 11:37:54 -0500
From: Kate Reilly
Subject: Re: [CSREESVolMon] Nitrogen (and other) publications sought

The Environmental Literacy Cycle has some good information on biochemical cycles, including nitrogen . At the end of the general info on the nitrogen cycle you’ll see resources cited for a number of nitrogen-related resources/materials.



Date: Wed, 13 Jun 2007 11:45:15 -0500
From: Susan S Brown
Subject: Re: [CSREESVolMon] Nitrogen (and other) publications sought

Our Heartland Regional Water Coordination Initiative has just released a publication on agricultural nitrogen management that belongs in your links:

Agricultural Nitrogen Management for Water Quality Protection in the Midwest.
Wortmann, C., alKaisi, M., Helmers, M., Sawyer, J., Devlin, D., Barden, C., Scharf, P., Fergusen, R., Kranz, W., Shapiro, C., Spalding, R., Tarkalson, D., Holtz, J., Francis, D. 2006.
Heartland Water Quality Bulletin, University of Nebraska Press, RP189.

The pdf document with bookmarks can be obtained online at:

A pdf image of the publication only is also available at:

I am copying this message to members of the Heartland Nutrient and Pesticide Management issue team, as they may have other recommendation for pubs from their own universities.



Date: Thu, 14 Jun 2007 17:10:43 -0400
From: Art Gold
Subject: RE: [CSREESVolMon] Nitrogen (and other) publications sought

Here are two excellent links on nitrogen and water quality from the
Ecological Society of America.  The first page of each document appears
blank, so scroll down before you give up:


Arthur J. Gold Ph.D.
Dept. Natural Resource Sciences
110 Coastal Institute
University of Rhode Island
Kingston, RI 02881
phone: 401-874-2903
Fax: 401-874-4561


Question 4

From: HANSON Steve []
Sent: Wednesday, June 22, 2005 6:56 PM
To: Volunteer water monitoring
Cc: Sandy Lyon
Subject: [volmonitor] Nitrogen testing kits and probes

I am requesting feedback from groups that have used nitrogen testing kits or probes. I’m interested in what kits/probes you have used, what the detection limits are (please specify mg/L as N or NO3), and how the kits performed for you. If you were able to compare the results from your kit/probe to samples analyzed at a laboratory, or any other quality control testing you did, I’d be very interested in how the samples compared .

I work with volunteer groups all over the state of Oregon who do water quality monitoring. I am trying to determine what methods could be used by Oregon groups to identify nutrient sources.

Thanks for your response.

Steve Hanson
Volunteer Monitoring Specialist
Oregon DEQ Laboratory
Phone: 503.229.5449
Toll Free: 1.800.452.4011
Fax: 503.229.6957
2020 SW Fourth Ave. Suite 400
Portland, OR 97201

Responses to Question 4

—–Original Message—–
From: Linda Green []
Sent: Wednesday, August 17, 2005 11:26 AM
To: HANSON Steve
Subject: RE: [volmonitor] Nitrogen testing kits and probes

I am program director of a volunteer monitoring program in RI, URI Watershed Watch, housed at Cooperative Extension. We have an analytical lab and use an Astoria-Pacific segmented continuous
flow nutrient autoanalyzer for our nutrient anlyses, since our waters are typically <2ppm in any form of nitrogen, which I think is pushing the limit on kits. I was fortunate that our Dean contributed ~ 75% of
the $42K it cost to purchase the autoanalyzer last year, it was replacing a 15 year old model that had been purchased by a professor I worked with. The prof departed without the analyzer, I took it over.

Best Wishes,

Linda Green
URI Cooperative Extension Water Quality
Department of Natural Resources Science
1 Greenhouse Road
Kingston, RI 02881-0804


Date: Wed, 22 Jun 2005 16:23:26 -0700
From: Lesley Jones
Subject: Re: [volmonitor] Nitrogen testing kits and probes

We only take grab samples and process in the lab. The methodology is:

TKN – EPA 351.2, sulfuric acid to pH<2 preservation, 4C, analyze within 48 hrs
Nitrate/Nitrite – EPA 300.0, 4C, analyze within 48 hrs
TP – EPA 365.3, sulfuric acid to pH<2 preservation, 4C, analyze within 28 days

The weird thing is that the Practical Quantitation Limit for TP is above the guideline of 0.05 mg/L. If there is a non-detect, the result is reported as one half of the PQL and is above the guideline. Therefore, no matter what result you get, the guideline is exceeded. The City of Bend lab is working on this issue to see if they can lower the PQL for TP.

Regarding nutrient probes, we have never used them, but I hear rumor that 'they are not as good as lab analyses methods'. I personally like to use meters and probes when possible, so I am interested to hear what you find out from this inquiry.

Have fun!

Lesley Jones, Water Quality Specialist
Upper Deschutes Watershed Council
Water Quality Monitoring Program


Date: Thu, 23 Jun 2005 10:18:42 -0400 (EDT)

Steve, our nutrient samples are analyzed by the National Parks Service-Cape Cod National Seashore (CCNS) lab. In the past we used the County health department lab and the detection limits were not sensitive enough (especially for P) because they were primarily set up to do drinking water samples, not lake/pond ones. I have passed on your question to the lab chemist at the CCNS in hopes she will reply.

I am not aware of any field instruments that are inexpensive enough for volunteer groups to use, which also meet the detection limit requirements, or would be approved by some of the state agencies who require analyses be done under an approved QAPP and a certified lab. We do use YSI DO meters in the field for DO, but follow up with a water sample for Winkler analysis at a lab (for marine samples), if DO readings are below 5.0 mg/L.

I am interested in what you find out!

Judy Scanlon
Orleans Water Quality Task Force


Editor’s note: Steve Hanson summarized the rest of the responses he received:

Responses are summarized in the following manner:

Nitrogen Testing Kits Comparison Information.
a. Kit Description
b. Method
c. Detectioin Limits/ Resolution
d. Performance
e. Comments

1. Jacqueline Fern OSU Extension Service Water Quality Educator
a. LaMotte Zn Based test Kit (Order Code 3354?)
b. Zinc Reduction Octa-Slide color comparator
c. “0” to 15 in increments of 1 ppm NO3-N
d. “goal is not to provide precise readings…but reasonably accurate
e. Recently switched from Hach colorwheel method b/c of concerns about

2. Natalie Galatzer, Prairie Rivers Network, Illinois Stream Team,
Water Quality Intern
a. LaMotte Kit Code 3354
b. Zinc Reduction Octa-Slide color comparator 0, 1, 2, 4, 6, 8, 10 and
15 ppm NO3-N
c. NA
d. It’s colorimetric, so you can see that perhaps the actual value
lies between 0 and 1, but you can’t determine what that value is with
this kit.

3. Ginger North, Stream Watch Coordinator, Delaware Nature Society,
302-239-2334×100, Fax 302-239-2473,,
a. LaMotte Field Kits Code 3110
b. Cadmium Reduction Octet color comparator
c. 0.025 (error? I can’t find any LaMotte kits with this low a DL) –
10 ppm NO3-N. LaMotte reports Range/Sensitivity as: 0.25,0.5,1.0, 2.0,
4.0, 8.0, 10.0 ppm NO3-N
d. “Under quality control testing the nitrate kits compare better than
the phosphate kits”
e. “The data is published by DE DNREC for their Watershed Assessment
Report – 305(b)”

4. Chris Sullivan, Project SEARCH Coordinator, (203) 734-2513, FAX
203-922-7833,, Center for
Environmental Research Education, Kellogg Environmental Center, 500
Hawthorne Ave., Derby, CT 06418
a. LaMotte Colorimetric analysis order code 3649-SC
b. Cadmium reduction with Colorimetric % Transmission determination.
c. 0.02 – 3.01 ppm NO3-N in increments increasing from 0.01 to 0.14
relative to magnitude of concentration. LaMotte reports sensitivity of
0.05 ppm NO3-N
d. “The results are slightly less reliable down at the lower end of
the scale, but have corresponded fairly well with the health lab values
in past years of Project SEARCH”
e. “We used to run replicate samples with the state health lab and the
school groups were usually statistically similar to the health lab

Question 5

From: Stepenuck, Kris
Date: November 29, 2012, 11:01 AM

I’m wondering what methods you use in your programs to assess phosphorus? We most often have our volunteers send water samples to a lab to be analyzed for total phosphorus, but we do have one local group using Chemetrics to assess phosphate. My experience with that kit is that it’s tough to read results at low levels. Have you had similar experiences? Do you have any recommendations for other kits/methods that students might use to assess phosphorus levels in the field or back at their schools?

Kristine Stepenuck
Water Action Volunteers Stream Monitoring Program Coordinator
445 Henry Mall, Rm 202
Madison WI 53706
608-265-3887 (MTF)
608-264-8948 (WR)
608-575-2413 (mobile)

Responses to Question 5

Higgins, Susan
Date: November 29, 2012, 11:06 AM

At MO Stream Team VWQM, we use the Hach phosphate colorimeter for phosphate measurement. These are usually reserved for higher trained volunteers because they are a bit expensive (around $400).

Susan J Higgins
Missouri Department of Natural Resources
Volunteer Water Quality Monitoring Coordinator
Volunteer Lake Monitoring Coordinator
P O Box 176
Jefferson City, MO 65102-0176
573-526-1002  FAX: 573-526-6802


From: Chris Riggert
Date: November 29, 2012, 11:29 AM

For our more advanced volunteers, we in Missouri provide the Hach Phosphate II Colorimeter ( measuring reactive orthophosphate.
It is a very accurate method and is very easy to use.  However, it isn’t cheap (lists for $420)…which is why we don’t provide this to everyone, but rather to those that have chosen to participate and attend the higher levels of trainings.
Really, the only issues we’ve had with these is that the vials MUST be kept clean and not wiped with a paper towel.  Spots or small scratches in the glass will skew the results because the light won’t refract properly.

Hope this helps!
Christopher M. Riggert
Stream Team Program
Volunteer Water Quality Monitoring Program Coordinator
Missouri Department of Conservation
P.O. Box 180

2901 W. Truman Blvd.
Jefferson City, MO  65102-0180
Phone: (573) 522-4115 ext. 3167
Fax: (573) 526-0990


From: Cheryl Cheadle
Date: November 29, 2012, 11:37 AM

I like the Hach kit (Ortho-phosphate model PO-19).  Yes, it is difficult to read at low levels.  I still like it.  Our QA sessions are often devoted to this.  We do find that volunteers get some of the steps wrong from time to time.  Again, why we have a stringent QA program.


From: Cheryl Nenn
Date: November 29, 2012, 11:38 AM

My experience with those (Chemetrics) kits is that they are always a weird tinge of green (instead of light blue). I have been interpreting that to be .15 based on the intensity (between .1 and .2 orthoP) but I’m honestly not sure. I did get a perfect .2 once in late summer! I took ortho-P last year and this year as well as sent samples to the SLOH for total P. Would be good to take a quick look at those and see if there are any correlations this year.

Cheryl Nenn
Milwaukee Riverkeeper
1845 N. Farwell Ave Suite 100
Milwaukee, WI 53202
(414) 287-0207 x2
(414) 378-3043 (cell)


From: James, Krista
Date: November 29, 2012, 1:19 PM

We use the Phosphate Phosphorus Hach Kit.

Krista C. James
Environmental Science Coordinator
Applied Science Program
Biology Department
327 Jarvis Hall Science Wing
410 10th Avenue E
University of Wisconsin-Stout


From: Rebecca Kauten
Date: November 29, 2012, 11:05 AM

IOWATER uses the Chemetrics kits.


Nancy Mueller
Date: November 29, 2012, 11:55 AM

NY’s CSLAP program: “send the samples to the lab” for TP (and etc.) analysis.  We don’t use any test kits at all.

Nancy J. Mueller, Manager,  NYS Federation of Lake Associations, Inc.
P.O. Box 84
LaFayette, NY  13084


From: Mike Daniels
Date: November 29, 2012, 12:28 PM
Here is some feedback from some of my colleagues at the University of Arkansas
From: “Andrew N. Sharpley”

My experience with kits for P, especially dissolved P, are that while they might be “convenient” they are not accurate enough to reliably measure the concentrations we routinely find in runoff.  You could use the kit on an unfiltered sample and get an estimate of reactive P or field-filter a sample.
The bottom line is that even though it might be a volunteer program you would like them to be getting information on forms of P that would have some meaning to the ongoing water quality and land use impact debate.


From: Mike Daniels
Date: November 29, 2012, 12:28 PM
Some more feedback
From: “Thad Scott”

My two cents on this…. From an in-stream water quality perspective, which is how nutrient criteria are likely to be applied, total P is generally the most reliable metric that integrates forms across temporal and spatial scales.

I also understand that the ease of measurement is a big consideration for these volunteer groups… but I would suggest that less data, collected in a more appropriate fashion, is actually better. The Dodds paper discusses the issues of ease of measurement and information gained… I hope this helps.—T


From: Jane Herbert
Date: November 29, 2012, 2:14 PM

You may have seen this before but it’s a summary of a study we did a few years ago on correlating transparency and P in surface water.  Essentially, it was a no go unless you were dealing with high fractions of particulate phosphorus.  Neither Dean or I are working with phosphorus these days though. [Editor’s note: Thus, please don’t contact them in follow up regarding this.]


From: Daniel Starr
Date: November 29, 2012, 2:20 PM

I think Vernier has some equipment for this, but you may have already been familiar with this.  When I talked to Vernier about getting the phosphate probe they said that it will generally not get any readings because the numbers are so low in “clean” environments.
Take care, Dan


From: Mary Holleback
November 29, 2012, 4:02 PM

Testing the Waters collects total phosphate data using Hach test kits (model # PO-24; catalog # 22501).  It’s $146 last time we purchased. Investment in the kit may be worth it if they’re going to stick with the testing over a number of years – otherwise maybe not.
Otherwise we’ve been sending our level 2 WAV water samples to the state lab.

Mary Holleback
Adult Programs Coordinator
Riveredge Nature Center
P.O. Box 26
Newburg, WI 53060


From: Janet Andersen
Date: November 29, 2012, 7:30 PM

I haven’t tried it yet, but my professor at school just told me about the Hanna Instruments HI 713 and HI 736  –   – he recommends it – approx $55 with a pack of reagents via Amazon.

Janet Andersen


From: Rathbun, Joseph (DEQ)
Date: November 29, 2012, 7:45 PM

Be careful with anything resembling a test kit – you need a detection limit of 0.01 ot 0.03 mg/L, and the simplest kits come in at around 1 mg/L.  Get the manufacturer to confirm the DL; the catalogs often say they go from “zero to 10 mg/L” or some such, but that’s nonsense – nothing measures down to nothing.  The original test kits of a few decades ago were designed for sewage treatment plants where influent P = 10 mg/L or so, so a DL of 1 was fine.  Some the same treatment plant folks, certainly not meaning any harm, guided development of some of the early volunteer monitoring handbooks.  And ever since some of our colleagues have used simple test kits that, for surface waters, are just random number generators.


From: Dave Ropa
Date: November 29, 2012 8:00 PM

Although we use the Lamotte kits, they aren’t typically accurate enough for the waters we test.  However, we often take sediment samples and compare the results of the levels in the sediment to those in the water and usually get more dramatic results.  – Dave


From: Kelly Eskew
Date: November 30, 2012, 8:52 AM

I have been using the Green (Global Rivers EE Network) test kits which are a LaMotte product as well. We only use these with teaching though not for river monitoring purposes.  You may have the same issue with it not being able to read low levels given it is a fairly basic test, it is also very subjective.  I have never compared them with other tests or a lab to see their accuracy.

However, they work great with getting water quality concepts across to students because the tests are simple to conduct, most tests only take 5 minutes and the color difference is easy for the kids to see. The sheet with the kit explains that the test tabs contain ammonium molybdate which reacts with phosphorous to form a phosphomolybdate complex. This is reduced to a blue complex by ascorbic acid. The test turns blue and comes with a color chart to interpret your results from 0-4 ppm depending on how blue the test turns.

Might be too basic for what you are doing but for what its worth, link to the website I order the from (acorn naturalists):

You can also order each test separately from their website rather than getting the entire kit so could just get the phosphorus kit.  Might be fun to try these because they are simple and fairly inexpensive and send samples to the lab for comparison.
Let me know if you find other better alternatives.


From: HANSON Steve
Date: November 30, 2012, 8:52 AM

I would second Joseph’s comments below and urge you to take a look at what concentrations you need to detect in order to answer your questions.  Furthermore I’ve seen problems with what test the kits actually do.  The kits I’ve seen only test for phosphate, which is fine if you filter your sample through a 0.45 micron filter and call your test dissolved or ortho-phosphorus.  Unfortunately the tests sometimes say total phosphorus.  Total phosphorus requires a digestion step in order to free up tightly bound phosphorus for reaction with the color reagent.  From my perspective, if you run the test without either digesting or filtering you are kind of in no man’s land, although you might be able to compare between samples.

Steve Hanson
ODEQ Lab:  Volunteer Monitoring Coordinator
Ph: 503.693.5737


From: Thorpe, Anthony Paul (
Date: November 30, 2012, 8:52 AM

The Lakes of Missouri Volunteer Program is housed in the University of Missouri and we use our own lab to analyze phosphorus. Some of our lakes consistently have 5 or 8 ug/L of total phosphorus. I have yet to see a test kit that can accurately measure even ten times that. When you are only looking at the reactive phosphorus, the concentration will be even lower. We’re finding that many commercial labs can’t even get that low. That is not a brag about our lab, but rather a statement about where the demand for nutrient testing is. My thought is that until nutrient criteria kick in, most of the commercial labs and available test kits will be set up for the sewage treatment industry.

Tony Thorpe
Coordinator, Lakes of Missouri Volunteer Program
302 ABNR University of Missouri
Columbia, MO 65211
Phone: 1-800-895-2260
Fax: 573-884-5070
Skype: lmvptony


From: Linda Green
Date: November 30, 2012, 10:44 AM

The URI Watershed Watch program, housed at URI Cooperative Extension, uses an Astoria-Pacific (API) segmented flow autoanalyzer to analyze nutrients. Total P and total N are simultaneously analyzed after a persulfate digestion. Kits would never work in our waters some as low as 5 ug/l (ppb) total P.  Lots of rigorous cleaning too! If anyone want the details I can send you our SOP or QAPP.

A bit of chemistry –  many kits express results as “phosphates” (PO4) where most scientists/agencies/VM programs express results in terms of phosphorus, in the original query, when filtered, dissolved reactive phosphorus (PO4-P). To convert ppb phosphates to  ppb phosphate-as-P, you must divide the molar weight of phosphate (103= 1 P (39) plus 4 oxygen@ 16)) by that of phosphorus (39).  103/39 = 2.64.   If your water is 100 ppb phosphate, it is 38 ppb phosphate-P.  Conversely, if it is 100 ppb phosphate-P it is 264 ppb phosphates.  The same applies to nitrates vs nitrate-N.  So you need to be very careful, especially when comparing these kit results to other results. It’s not quite comparing apples to oranges, more like macintosh to red delicious apples.

Linda Green
Program Director
URI Watershed Watch
102 Coastal Institute,
1 Greenhouse Road
Kingston, RI 02881
401-874-2905 (v)

Project Lead,
Extension Volunteer Monitoring Network


From: Paul Mack
Date: Dec 1, 2012

Do the students have access/experience with test equipment like spectrophotometers?

We have used EPA-approved Hach colorimetric method #8048 (orthophosphate/ascorbic acid) for over a decade and are satisfied with its results. It is a single-reagent method that is safe for older students in the presence of an adult, and can be used in both portable (field) and bench-top spectrophotometers.

As Linda pointed out in her email yesterday, this method returns PO4, which arithmetically converts to the more common P.

Paul Mack
River Prairie Group
Sierra Club – DuPage, IL


From: Nancy Mesner
Date: Dec 2, 2012

Just a note to make sure everyone reading this exchange understands that these tests provide the ionic form of phosphorus (PO4) and NOT total phosphorus. Total phosphorus analysis requires a digestion (oxidation) step which, to my knowledge, cannot be done with any of the field tests.

PO4 is the most biologically available form but often is below detection limits. In our part of the country, at least, total phosphorus is the form of P that the state agencies are considering in their discussions of phosphorus standards.

Nancy Mesner, Associate Professor, Dept of Watershed Sciences
Associate Dean, College of Natural Resources
Extension Water Quality Specialist
Utah State University, Logan, UT 84322-5210
office – 435 797 7541
cell- 435 770 2363


From: Iles, Jerome
Date: Deceber 3, 2012

As far as I know, in Ohio only grab samples / lab evaluation is done.


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