Comparison of Different Methods for Detecting Irrigation Canals Leakage
This research investigates some field methods to evaluate water leakage from irrigation canals, in order to find a reliable method of identifying and quantifying losses. This study was conducted in two canal lines in Piedmont, north-western Italy, which have different hydraulic, morphological, geological and hydrogeological contexts. A hydrogeological characterization of the study area was carried out for every investigated canal, in order to evaluate the relationships between groundwater and canal water. The water losses from irrigation canals were subsequently estimated using various methods. The methodologies are: empirical formulas, inflow-outflow test and two tracers method. Inflow-outflow test is easy to apply and efficient; however it sometimes is inadequate because of the high instrumental error, especially in canals with low velocity and discharge. The two tracers method is considered a more rigorous methodology, with a low error. This method is not reliable, however, in cases of low discharge and laminar flow, resulting in inadequate tracer diffusion. The comparison of the results shows that the empirical formulas heavily underestimated the real amount of the losses. The results of inflow-outflow method and two tracers method are similar, both in sandy-gravelly and impermeable bed canals.
KeywordsIrrigation canal Water losses Empirical formula Inflow-outflow test Two tracers method
- Bertrand-Krajewski JL, Cardoso MA, Ellis B, Frehmann T, Giulianelli M, Gujer W, Krebs P, Pliska Z, Pollert J, Pryl K (2005) Towards a better knowledge and management of infiltration and exfiltration in sewer systems: the APUSS project. In Proceeding of the 10th International Conference on Urban Drainage. Copenhagen, Denmark, 21–26 August 2005, p 8Google Scholar
- Buchanan TJ, Somers WP (1969) Discharge measurements at gauging stations, vol 3 (USGS—TWRI), p 65Google Scholar
- Comina C, Lasagna M, De Luca DA, Sambuelli L (2014) Geophysical methods to support correct water sampling locations for salt dilution gauging. Hydrol Earth Syst Sci Discuss, 11: 5115–5142. DOI: 10.5194/hessd-11-5115-2014
- De Luca DA, Comina C, Destefanis E, Marzano F, Carbotta G, Dino G, Passarella I, Masciocco L, Sambuelli L, Perotti L, Lasagna M, Clemente P, Bonetto S (2012) Definizione di linee guida per la valutazione delle perdite dei canali irrigui. http://www.regione.piemonte.it/agri/politiche_agricole/sibiweb/dwd/canaliPerdite/dipScienzeTerra.pdf. Accessed 2 May 2014
- Dhillon GS (1967) Estimation of seepage losses from lined channels. Indian J Power River Valley Develop 17:16–20Google Scholar
- Doorenbos J (1963) A literature survey of seepage in canals: preliminary report l7. ILRI p. 59Google Scholar
- International Organization for Standardization (1979) Liquid flow measurement in open channels: velocity area methods, 2nd ed. ISO 748, GenevaGoogle Scholar
- Kraatz DB (1971) Irrigation canal lining. Irrigation and drainage paper no 2. FAO, Rome. p. 178Google Scholar
- Lotti (1974) in “Canali”. http://host.uniroma3.it/docenti/volpi/infrastrutture_idra_2/canali.pdf. Accessed 20 july 2014.
- Rieckermann J, Gujer W (2002) Quantifying exfiltration from leaky sewers with artificial tracers, In Proceedings of the International Conference on “Sewer Operation and Maintenance”. Bradford, UK, 26–28 Nov 2002, p 8Google Scholar
- Rieckermann J, Borsuk M, Reichert P, Gujer W (2005) A novel tracer method for quantifying sewer exfiltration. Water Resour Res 41(5):20Google Scholar
- Worstell RV (1976) Estimating seepage losses from canal systems. J Irrig Drainage Div 102:137–147Google Scholar