This site page relates to page 7 of your workbook:

PART 6: MAPPING AND ORIENTATION

Rocky Creek Dam map 

Examine this digital copy of a topographical map of the area, following the link above, to answer the question in Part 6: Mapping and Orientation on page 7 of your student workbook.

Question a: What is the title and map code number for this area?

The title and map code appear on the "cover' of the map sheet. The Title appears in capital letters. The map code is 6 characters  long with a dash in between the fourth and fifth characters and appears in the section with a green background directly under the title.  

Question b: Identify the scale and contour interval of the map.

The scale is also shown in this section. The scale, expressed as a ratio  (1: X) can be interpreted to mean that 1 cm on the map represents X cm on the ground. Use this ratio to answer question c) in your workbook. Contour lines connect areas of equal elevation.  They will indicate the degree of slope in areas of the maps (contour lines close together indicate steep areas). The contour interval refers to the change in elevation between contour lines. The contour interval is shown directly below the scale bar at the top of the legend of the map. 

Question c: How many metres are represented by 1 cm on this map?

Question d: Provide a grid reference for the spillway.

A full grid reference involves reference to a mapsheet (which you have provided above) and a six digit number to represent the location of a feature on a map. 

• The first three numbers represent the Easting of the feature determined by reference to the horizontal scale of the map. 

• The last three numbers represent the Northing of the the feature determined by reference to the vertical scale of the map.

**An easy way to remember which numbers go first is to say to yourself  that you need to crawl before you can walk -go horizontal until you go vertical.

To determine the Easting locate the grid line immediately to the left of  the feature. Follow this line down to the horizontal scale at the bottom of the map. These two numbers will be the first two numbers of your grid reference. Now estimate how many tenths of the grid square the feature is to the right of the grid line. Add this number to the two numbers above.

To determine the Northing locate the grid line immediately below the feature. Follow this line along to the vertical scale at the side of the map. Read the two LARGE numbers identifying the grid line. These two numbers will be the first two numbers of your grid reference. Now estimate how many tenths of the grid square the feature is above the grid line. Add this number to the two numbers above.

This will give you the six number grid reference for the feature. 

The full grid reference would be expressed as

MAPTITLE  XXXX-XX   EEENNN

Further information about grid referencing can be found at:

http://sarc.org.au/wp-content/uploads/2016/03/UNDERSTANDING-GRID-REFERENCES.pdf 

Question e: Stand at the picnic tables overlooking Rocky Creek Dam.

What is the bearing to the dam wall?

What is the bearing to the car park?

To complete section e),  imagine you are standing at one of the picnic tables at the  picnic area at rocky creek dam. The area reference (Identifying the grid square that the picnic area is in) is AS 3233. The bearing to a point is the angle measured in a clockwise direction from the north line.  In the field a bearing would be determined using a compass. Using a paper map you would start by lightly penciling a line between the features you wish to measure the bearing between. You might also place an arrow on the line to indicate which way the bearing is being read. Place the center of a protractor (or compass) directly over the feature you are reading from (ie the picnic tables) and align the zero point of the protractor with North (that is in line with a vertical grid line). You can read the bearing directly from the protractor (or compass) i.e. the number on the protractor that the lightly penciled line you have drawn aligns with. The bearing indicates the direction the second feature (e.g. dam wall) is from the first feature. It is given as three digit number (BBB°).  Bearings are usually given to within 5 degrees of accuracy. You might also estimate a bearing using the cardinal and sub cardinal points (N, NE, E, SE, S, SW, W, NW etc). A three figure bearing would be considered appropriate for the exercise in your work book.

 You can use the method above over a computer screen. However you will have to imagine the line indicating the bearing between the features rather than penciling it in. As this will be an estimate it would be safest to indicate the bearing rounded to the nearest cardinal/sub cardinal point. 

You can estimate the length of a feature by measuring it on the map and referring the scale and calculating accordingly (see b)and c) above) or by using the scale bar at the top of the legend. If you use the scale bar on a computer screen it is important not to change the level of zoom when moving between the feature and the scale bar. 

The names of the two creeks that flow into the dam can be found on the adjoining mapsheet:

http://maps.six.nsw.gov.au/etopo/geopdf/25k/9540-1N%20HUONBROOK.pdf