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Under normal river flows, when reservoir releases are limited to meeting only downstream water needs, the ground water hydraulic gradients from lands along the river are generally toward the river, with ground water basins discharging water to the river. There are areas with relatively shallow depths to ground water along the river. In these areas, at the Floodway elevation flow, or even lesser flows in excess of downstream water needs, the increase in river elevation would either reverse the ground water gradient, with the river discharging water to the ground water system, or diminish the gradient to the river, resulting in little or no discharge of ground water to the river. In either of these cases, ground water table elevations along the river will increase and may, in sensitive areas, result in water supply and waste water disposal problems, loss of land productivity as well as property damage. Such areas mayor may not experience surface water flooding. Compensation for losses and damages caused by flood-related high ground water is generally not provided under the National Flood Insurance Program. 0J2228 . DISCUSSION . On only a few occasions since Hoover Dam closure in 1935 have river flows in various reaches of the river even approached the Floodway elevation flow. To prevent or reduce damages that may occur with associated high ground water levels, high ground water-prone areas should be identified and reflected in the development plans and flood plain management planning and practices. Section 7 of the Floodway Act provides for the use of federal expenditures or financial assistanc'e within the Colorado River Floodway for remedial or corrective actions, including, but not limited to, drainage facilities essential to assist in controlling adjacent high ground water conditions caused by flood flows. It is recognized and understood that drainage or pumping facilities and other corrective measures needed may, of necessity, extend to or be required for areas outside the Floodway and that the provisions for the use of federal expenditures or financial assistance should apply to such facilities and measures. RECOMMENDATION . It is recommended that on non-Indian lands, and at the request of and in cooperation with local entities, the Bureau of Reclamation, assisted by the United States Geological survey, conduct an investigation of potential high ground water-prone areas at the Floodway elevation flow. Recommendations should be developed for potential mitigation III-20