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<br />and opInIOns of persons of various <br />professions. The participants were selected to <br />include representatives of public agencies (at <br />all levels of govemment), engineering firms, <br />land developers, law firms, and special <br />districts having stormwater management <br />responsibilities. <br />The attitudes of public officials, land <br />developers, lawyers and engineers were <br />discussed at these symposia. Many of the <br />symposia participants were persons who had <br />experience in some aspect of providing or <br />operating storm water detention facilities, or <br />who were interested in applying the <br />techniques. Their attitudes and opinions were, <br />therefore, based for the most part on personal <br />experience. <br />Generally these people were favorable in <br />their attitudes towards on-site detention as a <br />method for managing urban runoff. Only the <br />land developers and their lawyers expressed <br />reservations about the use of the technique. <br />Their major objections were to the <br />inflexibility of local laws and requirements <br />which afforded them little, if any, <br />opportunity to use alternative methods for <br />handling stormwater runoff. They told of <br />cases where other storm water management <br />methods might prove to be better than the <br />method specified by local legislation or <br />regulations - where the rigidness of the law <br />prevented the use of alternative methods. <br />They also felt that the use of large, <br />jointly-used detention facilities was preferable <br />to the use of a large number of smaller <br />individual detention facilities each of which is <br />intended for use by only a single <br />development. <br />Questions of long-term effectiveness and <br />beneficial use were discussed at the symposia. <br />Although detention facilities appear to be <br />useful and beneficial at the present time, <br />some participants raised the question of the <br />desirability and effectiveness of the method as <br />a long-term solution to flooding problems. <br />Large commitments of land made today <br />might prove to be unjustified in the future, <br />especially if other methods of stormwater <br />management that do not require large land <br />commitments can be satisfactorily used in lieu <br />of on-site detention techniques. <br /> <br />Engineering Studies <br />The bibliography included in this report <br />contains many references to engineering <br />studies that have favored the use of detention <br />techniques for management of stormwater <br />runoff. In some instances, the detention <br />technique is favored because it reduces the <br />size, and hence the cost, of sewer pipes <br />needed for storm water drainage because the <br />runoff is discharged from the detention <br />facilities into the sewers at a low flow rate <br />over a long time period. In other instances, <br />detention of runoff is favored because the <br />detention facilities can enhance the aesthetics <br />and multiple-purpose use of the open space <br />provided in a land development. <br />There are many cases where on-site <br />detention of runoff is not favored over other <br />methods. Sufficient space is sometimes not <br />available for the needed facilities. In some <br />instances, representatives of local public <br />agencies having jurisdiction over storm water <br />managemen t fear that the maintenance <br />problems will outweigh the advantages of the <br />de t en tion method. This attitude is <br />understandable because storm sewers usually <br />require little maintenance and are out of <br />sight, whereas storm water detention facilities <br />usually require an appreciable amount of <br />maintenance effort and are usually visible to <br />the public. Finally, the use of storm water <br />detention techniques are not favored in some <br />areas where downstream flooding is not <br />regularly a major problem. A city on a large <br />lake, for example, may prefer to discharge the <br />stormwater as quickly as possible into the <br />lake. <br />Summary: The use of on-site detention <br />of stormwater runoff is not commonplace; <br />however, the technique has been in use for at <br />least 15 years. As urbanization progresses and <br />run 0 ff flow rates from developed land <br />increase, the need for effective flood control <br />and stormwater management becomes more <br />evident. The use of storm water detention <br />methods to reduce peak runoff flows is <br />gaining in favor. This technique is compatible <br />with the public's desire to make our cities <br />more enjoyable by the inclusion of open <br />space and recreational facilities. This public <br />attitude has been instrumental in promoting <br /> <br />10 <br />