Laserfiche WebLink
<br /> <br />e,., <br />ro <br />ll- <br />t.\:) <br /> <br />dissolved salt. Return flows may be aggravated by non- <br />associated sources of pollution as natural salt flows, <br />mining, and oil field operations. Additional sources <br />including municipal, commercial and industrial waste <br /> <br /> <br />discharges, together with runoff from urban~ construction, <br /> <br />highway and agricultural sources may augment return flow <br />salinity. <br /> <br />. Q!:i9.in Q1 E~!!!!:!l [lo~ <br /> <br />Return flows originate from both surface and subsurface <br />sources. Surface sources include bypass water, tailwater <br />(wastewater), and the incidental source, precipitation. <br /> <br />Bypass water is that diverted for irrigation but returned to <br /> <br /> <br />the source without having been applied to the land. <br /> <br />Tailwater is the excess remaining after an irrigation and is <br /> <br /> <br />hopefully retained in ditches or in ponds. The subsurface <br /> <br /> <br />source is water which has percolated through the soil <br /> <br /> <br />profile. This water finds its way either to the zone of <br /> <br />ground water saturation o~to the stream through artificial <br /> <br />drains or by shallow diffuse. seepage (non-point sources) <br />along the stream bank. <br /> <br />Excessive application of irrigation water often results <br />in tailwater losses as shown in Figures 2 and 3. If <br /> <br />12, <br />