Minnesota Waters Research Articles

Elevated Water Tank Freeze‐Ups

This joint discussion on elevated storage tank freeze‐ups was presented at the 1965 AWWA North Central Section meeting at Fargo, North Dakota. John R. Branch of the Minnesota Water Company, Inc., St. Paul, Minnesota, reports on a freeze‐up experience, the facilities of the water system involved, the events and conditions preceding the freeze‐up, and the corrective measures taken. George J. Toman, a consulting engineer of Mandan, North Dakota, reviews the concept and precept of water storage tank freeze‐ups and suggests several devices to prevent freezing.

Minnesota's Rocks and Waters: A Geological Story

Minnesota's Rocks and Waters: A Geological Story

Gill Nets for Sampling Fish Populations in Minnesota Waters

Abstract Reliability of standard experimental gill nets for estimating comparative size of perch, pikeperch, and pike populations is considered in the light of 31 series of gill-net catches from Minnesota lakes. Factors influencing the catch of gill nets are discussed. Because of the wide range of errors associated with means of series of gill-net catches, comparison of catch means at a probability level greater than 80 percent appears to be not practically feasible. A table showing error of means of series of net catches at this probability level is included.

Fish-Population and Catch Data from Minnesota Lakes

From seining it is concluded that the average game-fish lake of southern Minnesota has a fish population of about 110 pounds per acre of which about one-sixth is made up of large predaceous species. Pike (Esox lucius) is the most widespread and, from the viewpoint of fishery management, the most valuable predatory fish in Minnesota waters. Pike is nearly always a co-dominant with largemouth black bass (Micropterus salmoides) in “bass-panfish” lakes and with yellow pikeperch (Stizostedion v. vitreum) in “walleye” lakes. As a check on populations of yellow perch (Perca flavescens) and small centrarchids, pike are probably more effective than either bass or pikeperch. A comparison of the poundage composition of the anglersˈ take with the poundage composition of the fish population found by seining shows that fishing pressure in Minnesota is much heavier for the large predaceous species than for the panfishes. Pikeperch are subjected to heaviest fishing pressure, with pike second. Rough-fish lakes in southern Minnesota were found by test seining to have an average of about 375 pounds of fish per acre, of which 280 pounds were rough fish, largely carp (Cyprinus carpio). An average removal of 97 pounds per acre per season over 25 years has had no permanent effect in reducing the size of carp and buffalo populations in 14 such waters. In general, rough fish appear to have little effect on the total poundage of game fish in southern Minnesota lakes. Rough fish are, however, usually associated with large populations of crappies (Pomoxis spp.) and somewhat reduced perch and pike populations. Gill-net and hoop-net catches and indices are considered. Fishing selectivity of gill nets and the use of poundage data from gill-net catches in judging the relationship between perch and predatory fish are discussed.

Some Indices of Lake Productivity

Abstract In an attempt to evaluate lake-survey procedures some of the chemical, physical, and biological measurements that have been considered possible indices of lake productivity have been examined in the light of 11 years of lake surveys and 6 years of pond rearing of yellow pikeperch. In Minnesota waters total alkalinity and total phosphorus appear to be the most valuable indices. Nitrogen is usually present in excess; sulphates are of most value in considering waterfowl areas; and chlorides, pH, and dissolved carbon dioxide are of little value in comparing waters and judging potential productivity. Potassium, manganese, and iron concentrations also are discussed. Quantitative plankton and bottom-fauna samples have been found unsatisfactory as productivity indices for ordinary lake surveys, and the distribution and abundance of larger aquatic plants are of greatest value when related to waterfowl management. In estimating the potential productivity and formulating fish-management plans for lakes the ...

Survey of Unaccounted‐for Water in Minnesota

Journal AWWAVolume 39, Issue 6 p. 539-542 Article Survey of Unaccounted-for Water in Minnesota Minnesota Section Committee Report First published: 01 June 1947 https://doi.org/10.1002/j.1551-8833.1947.tb17697.xAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat Volume39, Issue6June 1947Pages 539-542 RelatedInformation

Artesian Water in Minnesota as Illustrated by the Twin City Artesian Basin

In a general way the state may be divided into three geologic zones. The first is an area where igneous and metamorphic rocks are exposed or occur beneath the unconsolidated mantle of glacial drift. This includes all of the northeastern part of the state and a considerable area in the central part and along the Minnesota river valley. Igneous rocks have solidified from a molten condition and metamorphic rocks have been formed from pre-existing igneous and sedimentary rocks by heat, pressure, and movement. It is to be expected that both of these classes of rocks would have a low porosity and, therefore, yield little water. Artesian water is, therefore, rare in these rocks of low porosity, although sometimes found in fracture zones or in the porous upper portions of lava flows. From the point of view of extensive artesian supplies we may eliminate this area from consideration. The second geologic zone is a series of areas in western Minnesota,2 where relatively thin deposits of Cretaceous sandstones and shales are found beneath the glacial drift and lying on the igneous and metamorphic rocks below. At places, especially near Marshall, the sand-