{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,6]],"date-time":"2026-07-06T09:25:31Z","timestamp":1783329931950,"version":"3.54.6"},"reference-count":37,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2021,4,27]],"date-time":"2021-04-27T00:00:00Z","timestamp":1619481600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"ARC Linkage","award":["LP160100241"],"award-info":[{"award-number":["LP160100241"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>High-resolution data collection of the urban stormwater network is crucial for future asset management and illicit discharge detection, but often too expensive as sensors and ongoing frequent maintenance works are not affordable. We developed an integrated water depth, electrical conductivity (EC), and temperature sensor that is inexpensive (USD 25), low power, and easily implemented in urban drainage networks. Our low-cost sensor reliably measures the rate-of-change of water level without any re-calibration by comparing with industry-standard instruments such as HACH and HORIBA\u2019s probes. To overcome the observed drift of level sensors, we developed an automated re-calibration approach, which significantly improved its accuracy. For applications like monitoring stormwater drains, such an approach will make higher-resolution sensing feasible from the budget control considerations, since the regular sensor re-calibration will no longer be required. For other applications like monitoring wetlands or wastewater networks, a manual re-calibration every two weeks is required to limit the sensor\u2019s inaccuracies to \u00b110 mm. Apart from only being used as a calibrator for the level sensor, the conductivity sensor in this study adequately monitored EC between 0 and 10 mS\/cm with a 17% relative uncertainty, which is sufficient for stormwater monitoring, especially for real-time detection of poor stormwater quality inputs. Overall, our proposed sensor can be rapidly and densely deployed in the urban drainage network for revolutionised high-density monitoring that cannot be achieved before with high-end loggers and sensors.<\/jats:p>","DOI":"10.3390\/s21093056","type":"journal-article","created":{"date-parts":[[2021,4,27]],"date-time":"2021-04-27T21:18:20Z","timestamp":1619558300000},"page":"3056","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":33,"title":["A Low-Cost Water Depth and Electrical Conductivity Sensor for Detecting Inputs into Urban Stormwater Networks"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2097-1416","authenticated-orcid":false,"given":"Baiqian","family":"Shi","sequence":"first","affiliation":[{"name":"BoSL Water Monitoring and Control, Department of Civil Engineering, Monash University, Wellington Road, Clayton 3800, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8967-5853","authenticated-orcid":false,"given":"Stephen","family":"Catsamas","sequence":"additional","affiliation":[{"name":"BoSL Water Monitoring and Control, Department of Civil Engineering, Monash University, Wellington Road, Clayton 3800, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Peter","family":"Kolotelo","sequence":"additional","affiliation":[{"name":"BoSL Water Monitoring and Control, Department of Civil Engineering, Monash University, Wellington Road, Clayton 3800, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Miao","family":"Wang","sequence":"additional","affiliation":[{"name":"BoSL Water Monitoring and Control, Department of Civil Engineering, Monash University, Wellington Road, Clayton 3800, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anna","family":"Lintern","sequence":"additional","affiliation":[{"name":"BoSL Water Monitoring and Control, Department of Civil Engineering, Monash University, Wellington Road, Clayton 3800, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dusan","family":"Jovanovic","sequence":"additional","affiliation":[{"name":"BoSL Water Monitoring and Control, Department of Civil Engineering, Monash University, Wellington Road, Clayton 3800, Australia"},{"name":"Faculty of Civil Engineering, University of Novi Sad, Kozara\u010dka 2a, 24000 Subotica, Serbia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5799-6185","authenticated-orcid":false,"given":"Peter M.","family":"Bach","sequence":"additional","affiliation":[{"name":"Swiss Federal Institute of Aquatic Science &amp; Technology (Eawag), 8600 D\u00fcbendorf, Switzerland"},{"name":"Institute of Environmental Engineering, ETH Z\u00fcrich, 8093 Z\u00fcrich, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ana","family":"Deletic","sequence":"additional","affiliation":[{"name":"School of Civil and Environmental Engineering, Faculty of Engineering, Queensland University of Technology, GPO Box 2434, Brisbane 4001, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8845-6501","authenticated-orcid":false,"given":"David T.","family":"McCarthy","sequence":"additional","affiliation":[{"name":"BoSL Water Monitoring and Control, Department of Civil Engineering, Monash University, Wellington Road, Clayton 3800, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,4,27]]},"reference":[{"key":"ref_1","unstructured":"Sartor, J.D., and Boyd, C.B. (1972). Water Pollution Aspects of Street Surface Contaminants."},{"key":"ref_2","first-page":"914","article-title":"Urban land runoff as a factor in stream pollution","volume":"36","author":"Weibel","year":"1964","journal-title":"Water Pollut. Control Fed."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"203","DOI":"10.1016\/j.jenvman.2019.06.006","article-title":"Understanding spatiotemporal variability of in-stream water quality in urban environments\u2014A case study of Melbourne, Australia","volume":"246","author":"Shi","year":"2019","journal-title":"J. Environ. Manag."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"422","DOI":"10.1016\/j.watres.2016.11.027","article-title":"Should we trust build-up\/wash-off water quality models at the scale of urban catchments?","volume":"108","author":"Bonhomme","year":"2017","journal-title":"Water Res."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"837","DOI":"10.2166\/wst.2010.325","article-title":"Stormwater quality models: Performance and sensitivity analysis","volume":"62","author":"Dotto","year":"2010","journal-title":"Water Sci. Technol."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"7267","DOI":"10.1021\/acs.est.5b05870","article-title":"Smarter stormwater systems","volume":"50","author":"Kerkez","year":"2016","journal-title":"Environ. Sci. Technol."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"394","DOI":"10.1016\/j.scitotenv.2013.03.014","article-title":"Impact of dry weather discharges on annual pollution from a separate storm sewer in Toulouse, France","volume":"452\u2013453","author":"Deffontis","year":"2013","journal-title":"Sci. Total Environ."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"959","DOI":"10.1111\/j.1752-1688.2005.tb03780.x","article-title":"Dry and Wet Weather Flow Nutrient Loads from a Los Angeles Watershed 1","volume":"41","author":"McPherson","year":"2005","journal-title":"J. Am. Water Resour. Assoc."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"98","DOI":"10.1016\/j.scitotenv.2015.04.042","article-title":"Surface water sewer misconnections in England and Wales: Pollution sources and impacts","volume":"526","author":"Ellis","year":"2015","journal-title":"Sci. Total Environ."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"241","DOI":"10.1016\/j.jenvman.2015.01.050","article-title":"Contamination of stormwater by wastewater: A review of detection methods","volume":"152","author":"Panasiuk","year":"2015","journal-title":"J. Environ. Manag."},{"key":"ref_11","unstructured":"Pitt, R. (2004). Illicit Discharge Detection and Elimination, a Guidance Manual for Program Development and Technical Assessments, Center for Watershed Protection."},{"key":"ref_12","doi-asserted-by":"crossref","unstructured":"Schang, C., Henry, R., Kolotelo, P.A., Prosser, T., Crosbie, N., Grant, T., Cottam, D., O\u2019Brien, P., Coutts, S., and Deletic, A. (2016). Evaluation of techniques for measuring microbial hazards in bathing waters: A comparative study. PLoS ONE, 11.","DOI":"10.1371\/journal.pone.0155848"},{"key":"ref_13","unstructured":"HACH Company (2019, October 01). Submerged AV Sensor. Available online: https:\/\/www.hach.com\/flow-sensors\/submerged-av-sensor\/family?productCategoryId=54948588082."},{"key":"ref_14","unstructured":"HORIBA Scientific (2019, October 07). D-50 Series Handheld Water Quality Meters. Available online: https:\/\/www.horiba.com\/scientific\/products\/water-quality\/conductivity-meters\/details\/d-50-series-handheld-water-quality-meters-72\/."},{"key":"ref_15","doi-asserted-by":"crossref","unstructured":"Lockridge, G., Dzwonkowski, B., Nelson, R., and Powers, S. (2016). Development of a low-cost arduino-based sonde for coastal applications. Sensors, 16.","DOI":"10.3390\/s16040528"},{"key":"ref_16","doi-asserted-by":"crossref","unstructured":"Kumar, M.S., Chandra, T.R., Kumar, D.P., and Manikandan, M.S. (2016, January 22\u201323). Monitoring moisture of soil using low cost homemade Soil moisture sensor and Arduino UNO. Proceedings of the 2016 3rd international conference on advanced computing and communication systems (ICACCS), Coimbatore, India.","DOI":"10.1109\/ICACCS.2016.7586312"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"103","DOI":"10.1016\/j.procs.2014.07.059","article-title":"Wireless sensor network system design using Raspberry Pi and Arduino for environmental monitoring applications","volume":"34","author":"Ferdoush","year":"2014","journal-title":"Procedia Comput. Sci."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"3238","DOI":"10.48084\/etasr.2144","article-title":"An IoT based real-time environmental monitoring system using Arduino and cloud service","volume":"8","author":"Zafar","year":"2018","journal-title":"Eng. Technol. Appl. Sci. Res."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"5187","DOI":"10.1016\/j.watres.2009.08.020","article-title":"Locating illicit connections in storm water sewers using fiber-optic distributed temperature sensing","volume":"43","author":"Hoes","year":"2009","journal-title":"Water Res."},{"key":"ref_20","doi-asserted-by":"crossref","unstructured":"Rocher, J., Parra, M., Parra, L., Sendra, S., Lloret, J., and Mengual, J. (2021). A Low-Cost Sensor for Detecting Illicit Discharge in Sewerage. J. Sens., 2021.","DOI":"10.1155\/2021\/6650157"},{"key":"ref_21","first-page":"1","article-title":"Detection of untreated sewage discharges to watercourses using machine learning","volume":"4","author":"Hammond","year":"2021","journal-title":"NPJ Clean Water"},{"key":"ref_22","first-page":"328","article-title":"An inexpensive open-source ultrasonic sensing system for monitoring liquid levels","volume":"15","author":"Fisher","year":"2013","journal-title":"Agric. Eng. Int. CIGR J."},{"key":"ref_23","doi-asserted-by":"crossref","unstructured":"Wang, G., Gu, C., Rice, J., Inoue, T., and Li, C. (2013, January 20\u201323). Highly accurate noncontact water level monitoring using continuous-wave Doppler radar. Proceedings of the 2013 IEEE Topical Conference on Wireless Sensors and Sensor Networks (WiSNet), Austin, TX, USA.","DOI":"10.1109\/WiSNet.2013.6488620"},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"56","DOI":"10.4031\/MTSJ.52.2.7","article-title":"StormSense: A new integrated network of IoT water level sensors in the smart cities of Hampton Roads, VA","volume":"52","author":"Loftis","year":"2018","journal-title":"Mar. Technol. Soc. J."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"175","DOI":"10.1016\/j.sna.2014.01.040","article-title":"A self-calibration water level measurement using an interdigital capacitive sensor","volume":"209","author":"Chetpattananondh","year":"2014","journal-title":"Sens. Actuators APhys."},{"key":"ref_26","doi-asserted-by":"crossref","unstructured":"Loizou, K., Koutroulis, E., Zalikas, D., and Liontas, G. (2015, January 17\u201319). A low-cost capacitive sensor for water level monitoring in large-scale storage tanks. Proceedings of the 2015 IEEE international conference on industrial technology (ICIT), Seville, Spain.","DOI":"10.1109\/ICIT.2015.7125295"},{"key":"ref_27","unstructured":"TE Connectivity (2020, October 15). MS5837-30BA Ultra-Small, Gel-Filled, Pressure Sensor with Stainless Steel Cap. Available online: https:\/\/www.te.com\/commerce\/DocumentDelivery\/DDEController?Action=showdoc&DocId=Data+Sheet%7FMS5837-30BA%7FB1%7Fpdf%7FEnglish%7FENG_DS_MS5837-30BA_B1.pdf%7FCAT-BLPS0017."},{"key":"ref_28","unstructured":"Parra, L., Ortu\u00f1o, V., Sendra, S., and Lloret, J. (2013, January 6\u20138). Low-cost conductivity sensor based on two coils. Proceedings of the First International Conference on Computational Science and Engineering (CSE\u201913), Valencia, Spain."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"1034","DOI":"10.1016\/j.snb.2017.05.184","article-title":"Conduino: Affordable and high-resolution multichannel water conductivity sensor using micro USB connectors","volume":"251","author":"Carminati","year":"2017","journal-title":"Sens. Actuators B Chem."},{"key":"ref_30","unstructured":"TE Connectivity (2018, November 15). MS5803-01BA Miniature Variometer Module. Available online: https:\/\/www.te.com\/commerce\/DocumentDelivery\/DDEController?Action=showdoc&DocId=Data+Sheet%7FMS5803-01BA%7FB3%7Fpdf%7FEnglish%7FENG_DS_MS5803-01BA_B3.pdf%7FCAT-BLPS0038."},{"key":"ref_31","unstructured":"(2019, October 21). Dallas Semiconductor. DS18B20 Programmable Resolution. Available online: https:\/\/cdn.sparkfun.com\/datasheets\/Sensors\/Temp\/DS18B20.pdf."},{"key":"ref_32","unstructured":"Ratcliffe, M. (2019, January 15). Three Dollar EC\u2014PPM Meter. Available online: https:\/\/hackaday.io\/project\/7008-fly-wars-a-hackers-solution-to-world-hunger\/log\/24646-three-dollar-ec-ppm-meter-arduino."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"119","DOI":"10.1023\/B:EMAS.0000031719.83065.68","article-title":"Temperature-electrical conductivity relation of water for environmental monitoring and geophysical data inversion","volume":"96","author":"Hayashi","year":"2004","journal-title":"Environ. Monit. Assess."},{"key":"ref_34","unstructured":"(2020, April 15). HANNA Instruments. Waterproof Portable EC\/TDS\/Resistivity\/Salinity Meter\u2014HI98192. Available online: https:\/\/hannainst.com.au\/hi98192-waterproof-portable-ec-tds-resistivity-salinity-meter.html."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"1812","DOI":"10.1016\/j.watres.2007.11.009","article-title":"Uncertainties in stormwater E. coli levels","volume":"42","author":"McCarthy","year":"2008","journal-title":"Water Res."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"12","DOI":"10.1016\/j.jenvman.2019.04.009","article-title":"Testing of new stormwater pollution build-up algorithms informed by a genetic programming approach","volume":"241","author":"Zhang","year":"2019","journal-title":"J. Environ. Manag."},{"key":"ref_37","first-page":"149","article-title":"Understanding heavy metal and suspended solids relationships in urban stormwater using simulated rainfall","volume":"76","author":"Herngren","year":"2005","journal-title":"J. Environ. Eng."}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/21\/9\/3056\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T05:53:27Z","timestamp":1760162007000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/21\/9\/3056"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2021,4,27]]},"references-count":37,"journal-issue":{"issue":"9","published-online":{"date-parts":[[2021,5]]}},"alternative-id":["s21093056"],"URL":"https:\/\/doi.org\/10.3390\/s21093056","relation":{},"ISSN":["1424-8220"],"issn-type":[{"value":"1424-8220","type":"electronic"}],"subject":[],"published":{"date-parts":[[2021,4,27]]}}}