INLAND WATER SURVEY 389 
Arrangements have to be made, in some cases, for payment to observers, 
for local repairs and maintenance, and for some system of supervision. 
Storage and flow controls.—At locks, weirs, etc., on canals and rivers and 
reservoirs the openings of sluices and gates, etc., and times thereof, have 
to be recorded, in addition to water levels. 
(6) Checking and filing at the filing office-——When the observers’ returns 
come in, there is considerable routine work necessary in suitable tabulation 
of readings and in the completion of graphs with the necessary gauge post 
checks, etc. ‘There will also be conversion of water levels into flows and 
the compiling of records from all the returns. 
(c) Forms of records——The main record will be a table of water levels 
and flows; and, generally speaking, it will be necessary to tabulate the 
water level and flow for each three hours of the day and to average these 
flows for the day. 
During principal floods, on the smaller areas, a second table will be 
required, dealing with half-hour periods, the values for each half-hour 
being averaged before filling in the 3-hourly values on the principal table. 
Total flows will be arrived at between one low water and the next low 
water, and these will be amended by any changes in reservoir storage and 
by values of remaining flow down to a standard low water; these latter 
values will emerge from the records in the course of a few years. 
In some cases a diagram of water levels may be a convenient form of 
continuous record. 
(d) Analysis and publication : Analysis of records (Summary) : 
(i) Dry weather fall of a river, residual flow after cessation of rain 
and temporary storage on area. Estimates of low flow for 
extended droughts. 
(ii) Concentration times, rates of rise and fall, peak intensities and 
duration of floods. 
(iii) Aggregate flows of long periods. Impounded storage and over- 
flow of reservoirs. 
(iv) Relation of flow to rainfall during flood periods and analysis of 
losses. 
(v) Comparison of gaugings at various points on a river and on 
similar rivers. 
(vi)) Frequencies of flow magnitudes. 
Publication Generally, the publication of records is in the form of an 
abbreviation of the full records kept. 
A usual publication is a graph for the year, giving the day-to-day flow 
above a horizontal time scale. 
Another form of publication is that of the daily frequencies of flow 
magnitudes for each month or year. 
A more complete form of publication, amenable to analysis, would give 
the aggregate flow from some selected date and the residual flow and amounts 
of impounded storage at low-water levels. 
6. APPLICATION OF ROUTINE TO THE VARIOUS WATER INTERESTS. 
One requires to visualise this routine work in action with the present-day 
organisations. 
In what follows I am trying to visualise, in my own way, those little 
modifications and additions to existing measurements and records which 
will change the individual work of the several water interests into something 
which will embrace the whole survey of surface water in its passage to the 
