DRAINAGE OF WET LANDS OF SOUTHERN" LOUISIANA. 



71 



about 0.8 inch the present plant should work to much better advantage. The 

 canal that brings the water from the " front " lands should not be enlarged, as 

 the rapid run-off from these higher lands is at present largely responsible for 

 the flooding. It is doubtful if even a large increase in pumping capacity would 

 be effective if the present reservoir were not improved. With the reservoir 

 enlarged to the usual size of those on other districts, the present pumping 

 plant probably would be of sufficient capacity to give satisfactory drainage. 



The drainage from area No. 8 is disposed of by gravity instead of by pump- 

 ing. The internal canals are large and the outlet canal is of such size that, 

 except in the case of extreme storms, the fluctuation of the water surface in 

 the canals is small ; that is, the water is discharged very soon after it reaches 

 the canals. Twelve storm periods are included in the following table : 



Rainfall and run-off due to heaviest storms occurring on area No. 8, December, 



1909, to April, 1912. 



[Gravity drainage system.] 



Date. 



Rain- 

 fall. 



Run- 

 off. 



Condition of soil before 

 stormo 



Date. 



Rain- 

 fall. 



Run- 

 off. 



Condition of soil before 

 storm. 



1909. 



Inches. 



Inches. 





1911. 



Inches. 



Inches. 





Dec. 11 



0.00 



0.06 





Apr. 24 



1.05 



.12 





12 



2.74 



.12 





25 



.00 



.11 





13 



.00 



.34 





26 



2.72 



.59 





14 



.80 



.33 





27 



.50 



.81 





. 15 



.00 



.32 





28 



.00 



.73 





16 



.00 



.32 



Well drained. 



29 



.45 



.44 



Saturated. 



17 



.33 



.31 





30 



.00 



.40 





18 



.12 



.26 





May 1 



.99 



.55 





19 



.00 



.21 





2 



.48 



.50 





20 



.00 



.21 





o 



.18 



.36 





21 



.00 



.20 





4 

 5 



.18 

 .00 



.28 

 .19 





1910. 









Dec. 18 



.00 



.07 





Mar. 9 



.00 



.05 





19 



2.66 



.08 





10 



3.11 



.10 





20 



.00 



.44 





11 



.00 



.18 



Dry, 



21 



.26 



.34 





12 



13 



.00 

 .00 



.15 

 .12 





22 

 23 



.85 

 .25 



.28 

 .38 



Well drained. 



May 17 



.00 



.00 





24 



.00 



.35 





18 



.21 



.02 





25 



.32 



.27 





19 



2.83 



.08 





26 



.13 



.24 





20 



.00 



.06 





27 



.29 



.23 





21 



.27 



.07 



Very dry. 











22 



1.57 



,08 





1912. 









23 



1.25 



.11 





Jan. 6 



.13 



.18 





24 



.30 



.14 





7 



1.61 



.17 





25 



.00 



.12 





8 



.80 



.49 





July 17 



.73 



.12 





9 



.00 



.58 



Saturated. 



18 



.55 



.12 





10 



.00 



.38 





19 



.65 



.34 





11 



.02 



.28 





20 



.92 



.39 



^Saturated. 



12 



.00 



.23 





21 



.17 



.29 





Mar. 10 



.00 



.04 





22 



.37 



.23 





11 



2.30 



.12 





23 



.20 



.19 



J 



12 

 13 



.00 

 .00 



.42 

 .30 



Well drained. 



1911. 









14 



.45 



.23 





Mar. 21 



.00 



.02 





15 



.00 



.20 





22 



3.80 



.36 





Mar. 21 



.05 



.08 





23 



.00 



.62 





22 



3.60 



.24 





24 



.00 



.37 



Dry. 



23 



2.40 



1.09 





' 25 

 26 



1.15 



.00 



.38 

 .45 



24 

 25 



.00 

 .00 



1.78 

 .84 



•Well drained. 



27 



.00 



.38 





26 



.00 



.42 





28 



.00 



.24 





27 



.00 



.32 





Apr. 3 



.00 



.08 





28 



.00 



.25 





4 



.10 



.11 





Apr. 11 



.26 



.07 





5 



1.10 



.16 





12 



1.39 



.07 





6 



.00 



.12 





13 



.21 



.17 





7 



.00 



.08 





14 



2.10 



.71 





8 

 9 



4.03 

 .00 



.69 

 .98 



Well drained. 



15 



16 



.00 

 1.60 



1.42 



1.08 



Well drained. 



10 



.00 



.48 





17 



.00 



.69 





11 



1.15 



.42 





18 



.00 



.44 





12 



.00 



.49 





19 



.10 



.31 





13 



.00 



.33 





20 



.37 



.25 





14 



.00 



.25 



1 





21 



.00 



.20 





