Geography Reference
In-Depth Information
However, there are certain standard elements, which are common to
almost all type of water quality evaluation programmes. A generalized
structure of water quality evaluation programme consisting of twelve elements
is shown in Figure 1.
Prior to designing a water quality evaluation programme, clear-cut
objectives should be set on the basis of environmental conditions (pollution
sources), water uses (present and future), and water legislation.
Once the programme objectives are set, monitoring design is determined
based on review of existing water quality data, which is supported by
preliminary survey. In next step, various monitoring operations are performed
to collect water samples from selected sites in the field, and then, the collected
samples are analysed in laboratory.
Table 1. Summary of point and non-point sources of pollution
Point Sources
Non-Point Sources
1. Municipal and industrial
wastewater effluents
1. Return flow from irrigated agriculture
and orchards
2. Runoff and leachate from solid-
waste disposal sites
2. Runoff from crops, pasture, and
rangelands
3. Runoff from logging operations,
including logging roads and all-terrain
vehicles
3. Runoff and drainage from animal
feedlots
4. Urban runoff from small communities
and unsewered settlements
4. Runoff from industrial sites
5. Storm sewer outfalls from urban
centers
5. Drainage from failing septic tank
systems
6. Wet and dry atmospheric fall-out or
deposition over waterbodies (e.g., acid
rain)
6. Combined sewer overflows and
treatment plant bypasses
7. Mine drainage and runoff (also
oil fields)
7. Flow from abandoned mines and
mining roads
8. Discharges from storage tanks,
chemical waste piles, and ships
8. Runoff and snowmelt from roads
outside urban areas
9. Runoff from construction sites
9. Wetland drainage
10. Mass outdoor recreation and
gatherings
11. Military training, manoeuvres,
shooting ranges
10. Airport snowmelt and runoff
from deicing operations
After Johnson, 2009.
