{"id":5757,"date":"2021-01-24T10:33:20","date_gmt":"2021-01-24T10:33:20","guid":{"rendered":"http:\/\/versicolor.ca\/sandylakebedford\/?page_id=5757"},"modified":"2021-01-25T15:41:56","modified_gmt":"2021-01-25T15:41:56","slug":"ec","status":"publish","type":"page","link":"https:\/\/versicolor.ca\/sandylakebedford\/misc\/drafting-etc\/ec\/","title":{"rendered":"EC"},"content":{"rendered":"

‘workin on it<\/p>\n

“EC”<\/strong> is shorthand for Electrical Conductivity.\u00a0 It is a property of water routinely included in water quality measurements. Along with temperature and oxygen (and sometimes pH) it is one of the basic variables that is measured with multiparameter water-quality instruments to characterize “vertical profiles” of lakes.<\/p>\n

EC is a measure of the capacity of water to conduct electricity, a property than can be measured readily and reliably with very simple instruments.<\/strong><\/p>\n

The standard units for electrical conductivity in fresh waters are microsiemens per centimeter,\u00a0 \u00b5S\/cm<\/strong> or sometimes without the special symbol for “micro” as uS\/cm.<\/p>\n

EC increases with ionic content.<\/strong><\/p>\n

Conductivity is a measure of water\u2019s capability to pass electrical flow. This ability is directly related to the concentration of ions in the water. These conductive ions come from dissolved salts and inorganic materials such as alkalis, chlorides, sulfides and carbonate compounds.. Compounds that dissolve into ions are also known as electrolytes\u00a0 The more ions that are present, the higher the conductivity of water. Likewise, the fewer ions that are in the water, the less conductive it is. Distilled or deionized water can act as an insulator due to its very low (if not negligible) conductivity value. Sea water, on the other hand, has a very high conductivity. – Read more at Conductivity, Salinity & Total Dissolved Solids: What is Conductivity<\/a>?on fondriest.com<\/em><\/p><\/blockquote>\n

The “limnologically important ions<\/a>“<\/strong> are the cations Ca2+<\/sup> Mg2+<\/sup> Na+<\/sup><\/strong> \u00a0K<\/strong>+<\/sup>\u00a0 NH4+ <\/sup>and the anions HCO3–<\/sup><\/strong>, SO42-<\/sup><\/strong> Cl–<\/sup> <\/strong>NO3–<\/sup> F–<\/sup> CO32-<\/sup>; the bolded ions typically account for 99% of the EC.<\/p>\n

If all of the major ions (cations and anions) are measured, a “Theoretical Conductivity<\/strong>” can be calculated. Typically the calculated values are very close to observed values; if not it’s an indication that something has been missed in the ion analysis, e.g., metals that could be entering surface waters from\u00a0 mining operations.<\/p>\n

EC is influenced by temperature. So for precise comparison of EC values, EC values should be adjusted to a standard temperature.<\/p>\n

Conductivity increases approximately 2-3% per 1\u00b0C increase in temperature, though in pure water it will increase approximately 5% per 1\u00b0C 11. This variation is why many professionals use a standardized comparison of conductivity, known as specific conductance, that is temperature corrected to 25\u00b0C – from Fondriest<\/a><\/em><\/p><\/blockquote>\n

The meter we have been using for most EC measurements, the AP-2: AquaPro Water Quality Tester (EC)<\/a> provides Automatic Temperature Compensation<\/p>\n

Typical EC values<\/strong><\/p>\n\n\n\n\n\n\n\n\n\n\n
Water Type<\/strong><\/td>\nElectrical Conductivity<\/strong>
\n(uS\/cm)<\/td>\n<\/tr>\n
Distilled water<\/td>\n. 0.5 – 3<\/td>\n<\/tr>\n
Melted snow<\/td>\n2 – 42<\/td>\n<\/tr>\n
Tap water<\/td>\n50 – 800<\/td>\n<\/tr>\n
Potable water<\/td>\n30- 1500<\/td>\n<\/tr>\n
Freshwater streams<\/td>\n50 – 2000<\/td>\n<\/tr>\n
Industrial wastewater<\/td>\n10,000<\/td>\n<\/tr>\n
Seawater<\/td>\n50,000<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

*From Conductivity, Salinity & Total Dissolved Solids: What is Conductivity<\/a> on fondriest.com; except that the lowest value for freshwater streams was changed from 100 to 25 to better represent values in Nova Scotia. Most lakes without significant development or seawater influence\u00a0 in NS have values in the range 30 to 400 uS, the higher values commonly associated with lakes in areas of gypsum or limestone deposits. In the Halifax area, EC values of pristine lakes and associated streams are typically fall within the range 30-60 uS\/cm.<\/p>\n

TDS or Total Dissolved Solids<\/strong> is the weight of all particles smaller than 2 microns in water, expressed as milligrams per liter, mg\/L and is measured by measuring the weight remaining when all of the water in a sample has evaporated.\u00a0 \u00a0In “clean water”, TDS are made up mostly of ionic substances and there is a close\u00a0 relationship between TDS and EC, so\u00a0 TDS can be estimated from the more readily measured EC. The exact relationship\u00a0 varies with ionic composition (see Fondriest article<\/a>).\u00a0 \u00a0 “Dirty water” may include significant components of small non-ionic substances such as urea and hydrocarbons; for such waters, there may\u00a0 be a very poor relationship between TDS and EC\u00a0 (see Rusydi, 2017<\/a> for examples).<\/p>\n

Salt, Salinity\u00a0 <\/strong>\u00a0 EC increases with increasing content of “salts” as defined chemically<\/a>, so EC could be thought of as a measure of the salt content. \u00a0“Salty waters” are waters with sufficiently high content of common ions that they taste “salty”.\u00a0 “Salinity” is a term generally applied only to seawater. Seawater has\u00a0 highly consistent proportions of the major ions and so there is a highly consistent relationship between “salinity” as traditionally measured in seawater* and electrical conductivity; today salinity of seawater is generally determined by measuring its electrical conductivity and applying particular formulas or conversion factors to give the “salinity” in units that describe the weight of salt in a kilogram of seawater, typically g\/kg or “parts per thousand”, ppt. Typical seawater has values in the range of about 32 to 35 g salt\/kilogram of water (32-35 ppt).
\n__________________
\n*By determination of chloride content or the “chlorinity”; or from measurement of the weight of a sample of water of known volume at a known temperature, i.e. its “density”, the weight per unit volume.<\/p>\n

The units for salinity are similar to units for TDS, except TDS is expressed per liter of water not per kilogram; one kilogram of pure water occupies one liter (a density of 1 g\/mL) at 4 deg C<\/a>. The differences\u00a0 are very small numerically, but can be important in relation to oceanographic calculations that involve density.<\/p>\n

Sources of conductivity. <\/strong>To Add<\/p>\n

Some links & lit<\/strong><\/p>\n

Conductivity, Salinity & Total Dissolved Solids: What is Conductivity<\/strong><\/a>?
\nOn fondriest.com<\/p>\n

Calculating the conductivity of natural waters<\/a><\/strong>
\nRich Pawlowicz Limnol. Oceanogr.: Methods 6, 2008, 489\u2013501<\/p>\n

A Simplified Model to Estimate the Concentration of Inorganic Ions and Heavy Metals in Rivers<\/strong><\/a>
\nClem\u00eancio Nhantumbo et al., Water 2016, 8, 453 (pdf)<\/p>\n

Understanding Lake Quality<\/a><\/strong>
\nUS EPA 57 page pdf.<\/p>\n

Water on the Web: Ecoregions<\/strong><\/a>
\nIllustrate how EC and other variables differ between Ecoregions. Also view Water on the Web: Electrical Conductivity<\/a><\/p>\n

Electrical conductance \u2013 a versatile guide in freshwater science<\/strong><\/a>
\nJ.F. Talling 2009. Freshwater Reviews 2, pp. 65-78<\/p>\n

CAN YOU DETERMINE WATER HARDNESS FROM CONDUCTIVITY OR TOTAL DISSOLVED SOLIDS MEASUREMENTS?<\/a><\/p>\n

THE CONDUCTIVITY OF LOW CONCENTRATIONS OF CO2DISSOLVED IN ULTRAPURE WATER FROM 0-100\u00b0C<\/a>
\nTruman S. Light et al., 1995<\/p>\n

https:\/\/www.mt.com\/dam\/mt_ext_files\/Editorial\/Generic\/7\/Paper-THOR-Gray-CONDUCTIVITY_Editorial-Generic_1201100849793_files\/iwc_06-29_gray_conductivity.pdf. A Comprehensive Look at Conductivity Measurement
\nin Steam and Power Generation Waters<\/p>\n

file:\/\/\/Users\/davidpatriquin\/Downloads\/Bhateria-Jain2016_Article_WaterQualityAssessmentOfLakeWa.pdf
\nEC (electrical conductivity)
\nConductivity shows significant correlation with parameters such as temperature, pH value alkalinity, total hardness, calcium, total solids, total dissolved solids and
\nchemical oxygen demand chloride and iron concentration
\nof water. Conductivity in streams and rivers is affected
\nprimarily by the geology of the area through which the
\nwater flows. Streams that run through areas with granite
\nbedrock tend to have lower conductivity because granite
\nis composed of more inert materials that do not ionize
\n(dissolve into ionic components) when washed into the
\nwater (Gupta and Paul 2010). Streams that run through
\nareas with clay soils tend to have higher conductivity
\nbecause of the presence of materials that ionize when
\nwashed into the water. Ground water inflows can have the
\nsame effects depending on the bedrock they flow through.
\nDischarges to streams can change the conductivity
\ndepending on their make-up. A failing sewage system
\nwould raise the conductivity because of the presence of
\nchloride, phosphate and nitrate; an oil spill would lower
\nthe conductivity.<\/p>\n

Conductivity
\nTheory and Practice http:\/\/www.analytical-chemistry.uoc.gr\/files\/items\/6\/618\/agwgimometria_2.pdf<\/p>\n

soil EC measurement dS\/m
\nhttps:\/\/www.nrcs.usda.gov\/Internet\/FSE_DOCUMENTS\/nrcs142p2_053280.pdf<\/p>\n

Understanding
\nlake data. https:\/\/www.uwsp.edu\/cnr-ap\/weal\/Documents\/G3582.pdf. ***<\/p>\n

The presence of chloride (Cl\u2013) where it does not
\noccur naturally indicates possible water
\npollution. Chloride does not affect plant and
\nalgae growth and is not toxic to aquatic
\norganisms at most of the levels found in
\nWisconsin. Chloride is not common in Wisconsin
\nsoils, rocks or minerals, except in areas with
\nlimestone deposits. Figure 7 shows the
\ngeographic distribution of chloride in Wisconsin
\nlakes.
\nSources of chloride include septic systems
\n(chloride values of 50 to 100 mg\/l are common in
\nseptic tank effluent), animal waste, potash
\nfertilizer (potash = potassium chloride), and
\ndrainage from road-salting chemicals. Increases
\nin chloride, either seasonally or over time, can
\nmean that one or more of these sources is
\naffecting the lake.
\nAn increase in chloride from human or animal
\nwaste suggests that other nutrients are also
\nentering the lake. Higher chloride concentrations
\nfrom spring to fall may be the effect of lawn
\nfertilizer runoff or septic systems during heavy
\nuse by summer residents. Higher values in
\nspring after the snow melts may signify runoff
\nfrom drainage basins or highways as a major
\nsource of chloride. Since lakes vary in their
\nnatural chloride content, it is important to have
\nbackground data or a long term database to
\ndocument changes.<\/p>\n

Regeneration of dissolved substances in a seasonally anoxic lake:The relative importance of processes occurring inthe water column and in the sediments <\/a><\/p>\n

http:\/\/aquaticcommons.org\/5193\/1\/1984_52_davi_trea.pdf TREADING IN MORTIMER’S FOOTSTEPS: THE GEOCHEMICAL CYCLING
\nOF IRON AND MANGANESE IN ESTHWAITE WATER<\/p>\n

The electrolytic conductivity of pure water equilibrated with atmospheric CO2 is typically
\ntaken to be 1.05 \u00b5S\/cm
\nhttps:\/\/www.nist.gov\/system\/files\/documents\/srm\/260-142-2ndVersion.pdf<\/p>\n

…Why is pH measured in the first place? A good case can be made that in pure water it is
\nunnecessary to monitor pH since a conductivity measurement is simpler and assures high
\npurity. For example, if the conductivity is less than 0.06 \u00b5S\/cm then the pH must be
\nbetween 6.9 and 7.2\u2014the extremes possible with strong acid and base contaminants,
\nrespectively. This pH vs. conductivity relationship has been documented in graphic form
\nfor strongly ionized acids and bases and for weakly ionized carbon dioxide and ammonia
\ntypical of power plant samples.1,2,3<\/p>\n

Measuring the pH of pure water is difficult because of inherently low
\nsolution conductivity (between 0.056 and 10.0 microSiemens\/cm) or
\nresistivity (between 18.2 and 10 megohm\u2013cm at 25\u00baC). Several
\nproblem areas can lead to gross measurement errors in this type of
\napplication. Eliminating these potential interferences requires special
\nmeasurement considerations.
\nWhy Do We Need to Measure Pure Water pH?
\nThe measurement of pure water pH can be one of the quickest indicators of process contamination in
\nthe production or distribution of pure water. The presence of gaseous contaminants such as air or
\ncarbon dioxide will shift the pH of the pure water, indicating air or gas intrusion into the process line.
\nThe exhaustion of resin beds used to prepare or polish pure water can introduce contaminants that will
\ncause a shift in pH. These resin beds are typically cation and\/or anion exchange resins in a hydronium
\nion form (cation exchange) or hydroxide ion form (anion exchange). While conductivity measurements
\nwill clearly indicate an ionic leakage, pH measurement changes can be diagnostic as to which resin is
\nexhausted. If the pH increases, the cation resin bed is becoming exhausted; if the pH decreases, the
\nanion resin bed is becoming exhausted.
\nBoilers require pure water to reduce scaling and<\/p>\n

\"\"<\/a>https:\/\/www.emerson.com\/documents\/automation\/application-data-sheet-theory-application-of-conductivity-rosemount-en-68442.pdf<\/p>\n

Open Access
\nPublished: 08 June 2017
\nFrom Bacteria to Fish: Ecological Consequences of Seasonal Hypoxia in a Great Lakes Estuary ****
\nhttps:\/\/link.springer.com\/article\/10.1007\/s10021-017-0160-x<\/p>\n

https:\/\/wmich.edu\/sites\/default\/files\/attachments\/u486\/2015\/Koretsky2012.pdf<\/p>\n","protected":false},"excerpt":{"rendered":"

‘workin on it “EC” is shorthand for Electrical Conductivity.\u00a0 It is a property of water routinely included in water quality measurements. Along with temperature and oxygen (and sometimes pH) it is one of the basic variables that is measured with … Continue reading →<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"parent":5417,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-5757","page","type-page","status-publish","hentry"],"post_mailing_queue_ids":[],"_links":{"self":[{"href":"https:\/\/versicolor.ca\/sandylakebedford\/wp-json\/wp\/v2\/pages\/5757","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/versicolor.ca\/sandylakebedford\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/versicolor.ca\/sandylakebedford\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/versicolor.ca\/sandylakebedford\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/versicolor.ca\/sandylakebedford\/wp-json\/wp\/v2\/comments?post=5757"}],"version-history":[{"count":46,"href":"https:\/\/versicolor.ca\/sandylakebedford\/wp-json\/wp\/v2\/pages\/5757\/revisions"}],"predecessor-version":[{"id":5805,"href":"https:\/\/versicolor.ca\/sandylakebedford\/wp-json\/wp\/v2\/pages\/5757\/revisions\/5805"}],"up":[{"embeddable":true,"href":"https:\/\/versicolor.ca\/sandylakebedford\/wp-json\/wp\/v2\/pages\/5417"}],"wp:attachment":[{"href":"https:\/\/versicolor.ca\/sandylakebedford\/wp-json\/wp\/v2\/media?parent=5757"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}