Waterbury Democrat., 1900-12-18

ed matter can be removed by simple sedimentation combined With some sen tic action, and by utilizing also the natural How of the river as ar as prac- tica bIe, to- be presently described, we sfind that the more expensive chemical process is no longer essential. At Il r less expense results can now be ob- talned that will not make q nuisance Of the river at any time.s Nor would there be nuisance upon the adJon- ing land, The septic action of the tanks will be slight, and as these are covered there should be no offensive oQOrS scattered abroad.
 T. lie litter beds should not operate as bacteria tanks, in Which the sewage IS heIu qulescent for several hours. 10 have them operate ill such a manner would require d large expense 10 con- Struct water tight beds. Instead, they may be operated like ordinary inter- mitten filters, deeply and freely under drained, so as to allow of d rapid per cOIatiOn.
 When sewage is discharged into river it becomes dispersed aud diluted, which thereby exposes it to the action of the oxygen dissolved in the rivers water W hen this water is sufficient in quantity. it can effect a complete oxidation of the organic matter in the sewage, and no offensive Odor arises from the river while oxidation is in progress. When the dissolved oxygen is insufficient putrefaction will result and unpleasant odors will arise. Tie present quantity of sewage dis charged from the city of Waterbury into the Naugatuck river at it's low stages, is clearly too great for the amount Cf oxygen available to prevent putrefacton. But when the river flow is large, as it is during the latter part of winter and early part of spring. the ! quantity of SC wage is not yet toe great for the process of oxidation to pre- vail. If there may be some evidence l apparently pointing to the contrary, 1t only would be because the river has now in some of it's parts an accumula- ton of foul deposit. resulting from q slight velocity of the water and from deposits of matter washed down the stream during it's high stages-causes that would no longer exist in the meth cd of disposal now discussed.
 When river water is to be used fer drinking purposes, all sewage should if possible, be excluded therefrom, rr
 cause it may bring into the stream pathOgenic or diSease-creating bac- tera. When it is not used-and such is the case with the Naugatuck river below Waterbury-the quantity of sew age that may be discharged into a flowing river is measured by the nui- Sance that is caused by the pollution. This nuisance is partly due to the un- sightliness of sewage matter strand ing along the shores or on the shoals: 1lIt it is mainly due to the offensive odors that arise from putrefaction.
 To ascertain the amount of premis- S:ble pollution in stream, which is not to be used, for drinking purposes,
 we must proceed in an empirical man. ncr. Many similar cases have present cd themselves, and considerable expert Cnce is available.
 The best measure of river pollution
 is the number of persons whose sew
 age can be safely turned into stream i of given flew. Under tho conditions
 existing in the Naugatuck river below , Waterbury. it is my opinion that q
 minimum flow of seven cubic feet per second would render the sewage of eco persons quite inoffensive, and. in : fact unnoticeabe in the river. This - meas;lre agrees with the experience had in several rivers of Massachu- ! stts, our western rivers and European rivers.
 The flow of the Naugatuck river has l not been continuously meaSured. It Is - therefore necessary to estimate its flow
 on the basis of other data. For this ! pl:r1ose 1 have used the flow of the l Sudbury river in Massachusetts. be tween the year 1875 and the present : time The least flow occurred there 2 in 1880.
 The following table gives in cubic t feet per second the deduced avera "' . monthly flow and the minimum flow O : the Nau~atllck river at Platt's Mills
 a1Sn the greateSt nNnulatiCn whose | Sevvaoe wof1ld not cause q nuisance il [ the r'yer at such a time.