restored — and maintained consistently. 



This recommendation, as well as others relative 

 to aesthetics, is to be applied in the context of 

 local conditions. 



Numerical criteria of the National Technical 

 Advisory Subcommittee on Fish, Other Aquatic 

 Life, and Wildlife will provide guidance for water 

 management. 



In addition to supporting life forms of aesthetic 

 value, surface waters should themselves be aes- 

 thetically pleasing. Because natural conditions vary 

 widely, the Subcommittee recommends a series 

 of descriptive rather than numerical criteria for 

 this purpose. The criteria are intended in general 

 terms to provide for the protection of surface 

 waters from substances or conditions which might 

 degrade or tend to degrade the aesthetic quality 

 of water from other than natural sources. In 

 this context "natural sources" includes only sub- 

 stances or conditions which may affect water qual- 

 ity independent of human activities. Human ac- 

 tivities which cause degradation from otherwise 

 natural sources, such as accelerated erosion from 

 surface disturbances, are not considered to be 

 natural. The criteria are intended to cover degra- 

 dation "from discharges or waste." This phrase 

 is intended to cover pollution from all sources 

 attributable to human activities whether carried 

 in over-the-surface flow, point discharges, or sub- 

 surface drainage. 



The word "free" in the list of minimum require- 

 ments is acknowledged to be a practical impos- 

 sibility; the presence of pollutants in some degree 

 is inevitable. The Subcommittee assumes that ad- 

 ministrators and courts will interpret the term in 

 a manner that will accomplish the purposes of 

 the criteria. 



Recommendation: Surface waters should be free of 

 substances attributable to discharges or waste as 

 follows: 



(a) Materials that will settle to form objectionable 

 deposits. 



(b) Floating debris, oil, scum, and other matter. 



(c) Substances producing objectionable color, odor, 

 taste, or turbidity. 



(d) Materials, including radionuclides, in concentra- 

 tions or combinations which are toxic or which 

 produce undesirable physiological responses in 

 human, fish and other animal life, and plants. 



(e) Substances and conditions or combinations thereof 

 in concentrations which produce undesirable 

 aquatic life. 



Substances and conditions referred to in (e), above, 

 would include factors such as excessive nutrients and 

 temperature elevation. Undesirable aquatic life would 

 include objectionable abundance of organisms such as 

 a bloom of blue-green algae resulting from discharge 

 of a waste with a high nutrient content and an elevated 

 temperature. We would encourage the use of numerical 

 limitations on nutrients in specific waters where present 

 or future knowledge may permit or other water use 



requirements (e.g., public water supply) justify such 

 actions. However, the Subcommittee feels their recom- 

 mending numerical limitations that would meet the 

 many varying requirements of aesthetics for individual 

 waters and regions would result in nothing more than 

 a welter of numbers. 



The Subcommittee wishes to emphasize that 

 aesthetic qualities — notably color and clarity — of 

 natural waters vary sharply among regions and 

 within regions or even on specific streams, lakes, 

 reservoirs, bays, and estuaries. The recommended 

 criteria are intended to be applied in the context of 

 natural conditions. 



The Subcommittee considered recommending 

 numerical criteria for aesthetic uses. It concluded 

 that numbers would add littie to the usefulness 

 of descriptive criteria because the effect of vari- 

 ous substances on waters is so largely dependent 

 on local conditions. 



Quality above minimum requirements 



The Subcommittee notes that "Guidelines for 

 Establishing Water Quality Standards for Inter- 

 state Waters," published by the Department of the 

 Interior in 1966, provides that "water quality 

 standards should be designed to enhance (italics 

 supplied) the quality of water" and "in no case 

 will standards providing for less than existing 

 water quality be acceptable." 



Generally speaking — especially when psycho- 

 logical factors are considered — the aesthetic values 

 of water are enhanced by continuing improvement 

 in quality conditions in microbiological, chemical, 

 and physical terms and reduced as quality de- 

 clines. Aesthetic values may be best realized by 

 continuing efforts, as implied by the Water Quality 

 Act of 1965, toward enhancement of water quality 

 for all uses. 



Unique or outstanding waters 



Certain bodies of water in the United States 

 merit special considerations in establishing water 

 quality criteria and standards. Examples include 

 Lake Tahoe, Crater Lake, portions of Biscayne 

 Bay and other coastal and estuarine areas, rivers 

 (including a number which may be designated as 

 "scenic" or "wild" rivers under State or Federal 

 law) reservoirs, and lakes — ^waters which by rea- 

 son of clarity, color, scenic setting, or other char- 

 acteristics provide aesthetic values of imique or 

 special interest. The Subcommittee recommends 

 that such special waters be identified and specific 

 standards developed in each case to protect their 

 unique values. 



