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To investigate groundwater quality in the north of Jazmourian (Roudbar plain), 30 samples were collected and analyzed for evaluating drinking and irrigation status and associated health risks. In addition to major anions and cations, the fluoride and nitrate content of samples were analyzed using standard procedures. Nitrate levels range between 6.6 and 131 mg/L and exceed the WHO permissible limit in more than 23% and 80% of samples for adults and children, respectively. Fluoride amounts ranged from 0.4 to 4.8 mg/L in samples. The Flevel exceeded the WHO standard limit in 10% of samples. The EC level increases in fine-grained deltaic deposits toward the south. The concentrations of major ions (HCO 3 , Cl, SO 4 , Mg, Na, K) increase southwards, following the flow direction. There are, however, lateral (east-west) differences in water quality due to the influence of such factors as the rate of recharge and the type of bedrock. Wherever the redbeds comprise the bedrock and the recharge rate is weaker, the dissolved salts are higher in amount. The water quality index (IWQ) indicated that 13, 13, and 4 samples are in "good," "poor," and "very poor" quality classes, respectively. By using the irrigation water quality index (IWQI), eight samples were at "low restriction," nine samples at "moderate restriction," twelve samples at "high restriction," and one sample at "severe restriction" classes. The acquired findings revealed that the mean oral hazard quotient of nitrate was 1.14, 1.0, and 0.84, and for fluoride, it was 0.82, 0.72, and 0.61 for children, females, and males, respectively. The total hazard index for cumulative NO 3 and Ftoxicity exceeded the acceptable level in 76.67%, 66.67%, and 56.67% of samples for children, females, and males, respectively.

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A qanat is a kind of subterranean horizontal tunnel and usually excavated in soft sediments. It conducts groundwater to the surface at its emerging point. In addition to the tunnel, each qanat contains anywhere from several to hundreds of vertical wells for removal of dig materials and ventilation of the tunnel. These wells get increasingly deep until the deepest and last one, which is known as the mother well. According to the literature, qanat was first developed around 800 to 1000 bc in northwest of Iran and afterward was utilized in many other countries in Asia, Africa, southern Europe, and even (through independent invention) in the Americas. The areas utilizing the qanat have three characteristics in common: the shortage of surficial water (streams) indicating an arid or semiarid climate; suitable topographical slopes that help conduct groundwater to the surface for a distance by a gently sloping tunnel (qanat); and the presence of unconsolidated sediments (usually alluvial) that both act as subsurface reservoirs and as material that can be easily excavated using primitive tools. In another words, dry areas with mountain-plain topography, alluvial fans, and stream beds (wadis) are suitable for digging qanats. Major parts of Iran and some parts of the Maghreb have such conditions. This is why these two regions have been somewhat dependent on qanats for their water supply. Although the invention of qanats helped human settlement and welfare in drier countries, it had some negative impacts. The presence of humans due to qanats directly impacted the wildlife and vegetation cover of those areas. And in some cases, changes in the groundwater regime caused wilting and drying because of limited water resources for plants and wildlife. The history of qanat development may be viewed as undergoing three major stages in the dry zones of Iran and the Maghreb, as well as in many other countries where they are present. During the first stage, from 1,000 to 2,000 years after their introduction (depending upon the region) qanats rapidly proliferated as technology spread to new areas. During the second stage, new qanat construction halted, as they had been developed in almost all suitable areas. In the third stage, beginning in some places in the early 20th century, such factors as increasing demand for groundwater, technical developments in water well drilling, and problems with qanat maintenance and urban sprawl caused many qanats to dry out; their numbers in operation have dropped. This decline will continue with varying rates in different countries. Unfortunately, the rate of decline in Iran, the home country of qanats, is more than many other places. This is mainly due to mismanagement.