Preliminary surveys
of waterways are a process of getting to know your river. They
involve library research, understanding topographic maps and aerial
photographs (lots of fun that), as well as field trips to explore
the general features of the waterway and learn more about the
creatures that live in and around the waterway.
Not only are they enjoyable
experiences, preliminary surveys are absolutely necessary to a
good monitoring plan and other survey activities.
Before setting foot
in the field, you need to prepare a river map. Use a topographic
map(s) of the catchment area for strategic planning. (obtainable
from Local Council or Institute of Geological & Nuclear Sciences).
Enquire at your nearest
Lands Survey office or at your council to see if you can borrow
or view aerial photographs of the area to compare to the topographic
maps (Topographic maps are made from aerial photographs. Looked
at in stereo, they are even better than flying over the terrain).
Using these aids prepare your map and plan your research stations:
see where roads cross
the water giving easy access for monitoring.
pinpoint where concentrations
of people - or livestock - live along the waterway.
Work out where the
wetlands and estuaries are
(or were).
Identify the limits
of the stream / river (where it starts to where it runs out to
sea).
Identify the boundary
of the water catchment (all the land that drains into stream).
Mark sites where water
is drawn from river with a standard symbol to indicate size of
withdrawal. Use a graded size of symbol or a number suffix on
a 5 point scale.
Mark where effluent
/ pollutants enter the stream as piped flow, or as agricultural
or horticultural run-off (hash land run-off areas on map).
Mark the extent of
forested land in water catchment, including native forest, and
exotic forest.
Highlight usage areas
with boundary lines and distinct hashing or shading.
Mark the extent of
tidal flow in estuaries.
Ask permission well
in advance if you would like to enter private land to establish
a survey station. Be sure the landowner knows why you are doing
the survey and invite the landowner to attend the meetings of
your monitoring group and perhaps become a member and help do
the survey.
If the property is
some distance away, write a letter explaining why you are monitoring.
Be clear that the purpose is to improve the water quality of the
whole river and not an attempt to discover if they are doing something
wrong. The landowner may be concerned about public liability claims
if you should have an accident while on their property. Be aware
of the following courtesy considerations:
Volunteer safety must
be a top priority for water monitoring groups. Safety considerations
should include travel to and from the site, pier or bank stability,
testing procedures and weather conditions.
Start Simple
Before getting involved
with complex sampling programmes and the recording and analysis
of data, start simple.
After selecting a variety
of easy access places from your map and visiting these sites
to check them out first, arrange to take a class or community
group trip to look at different sections of the river to identify
and record general impressions at each site.
What makes a stream
or river healthy or unhealthy ? Visit sites that are in natural
surroundings and sites in an area believed to be polluted. What
differences can the group identify quickly and easily in the two
places? How could these be measured?
Which areas have been
subject to human interference? What sorts of evidence can the
group detect that indicates human interference?
What is the vegetation
like along different stretches of the river banks? How would this
change the health of the river?
How are people using
the river?
Against a chart of
the following categories make brief one line comments for each
site visited :
- Water flow
- Water colour
- Smells
- General description
(Broad, fast flowing river / narrow meandering creek)
- Natural floating
debris (eg leaves, twigs)
- Oil films on surface
- Froth (from detergents)
- Rubbish and or scums
along water's edge
- Dead fish seen floating
- Living fish seen
swimming
- River birds swimming
on / under water
- River birds feeding
from water or water's edge
- Public use for sport
- Public use for recreation
- Source of pipes draining
into stream
In a close up map
(drawn as a series of maps showing the stream in numbered
sections) identify:
Vegetation
Vegetation types alongside
the main channel : e.g. Mangrove fringing forest, Marshland (salt
meadow, rush marsh), Forested fringe (native or exotic), Agriculture,
Horticulture, Mown parkland, None (roadway or other permanent
hard surface).
Identify where banks
are overhung by vegetation or open.(affects quantity and diversity
of stream life)
Animals
At each site make a
record under the following categories:
Large animals or sign*
of animals seen alongside the waterway or on the water. Cattle,
horses, sheep, deer, pigs. (These animals break down stream banks,
eat shading vegetation and may pollute waterway with excessive
amounts of dung.)
Rabbits, rats, possums,
stoats, dogs, cats. (These animals eat bank vegetation or kill
wildlife associated with stream and may foul banks or waterway
Birds: including water
fowl (ducks, swans, coots, shags) swallows, kingfishers, waders
(pukeko, herons). (Birds can be good biological indicators of
water quality, reflecting presence of suitable food, shelter and
nest sites.)
[* Sign = droppings, footprints, browsed vegetation, fur and feathers.]
Small animals (>
5mm)
Snails, crustaceans, insects (larvae). There are several techniques used to catch and observe these specimens.
Human impacts
Map bridges, piers,
stormdrains, discharges, or other structures or facilities that
have an impact on the waterway.
Places for monitoring
stations
On the preliminary
survey map, indicate places were long term monitoring stations
might be set up. Show landmarks, bearings, roads, bridges or other
key details so the stations can be relocated exactly in future.
Take a set of photographs
of the stations to add to the base-line reference log book.
