Stormwater Map Investigative Questions
1. Examine the sub-watersheds in the City of London. What are some initial observations?
(Shape, size, path, etc).
-
Vary in size and shape
All lead to the Thames River
Stormwater management is a huge aspect of a City’s responsibility
The network of pipes to management stormwater is extensive.
2. Why do you think that some of the sub-watersheds have such straight lines that likely would
not occur naturally?
-
Sub-watersheds (and watersheds) and generally defined by topography.
City’s use this to their advantage as stormwater pipes are not pumped so gravity and
natural slopes are an essential aspect to ensuring a working system.
The pipes generally flow under streets, and our streets are usually straight, but the
system still takes into account the natural watershed.
3. Which direction is the Thames River flowing? Using the North Arrow on the map, answer
using proper names.
-
South-West
4. Would an oil spill in Medway Creek impact any of the other sub-watersheds? If so, why?
-
Since Medway Creek flows directly into the Thames River (North Branch), it will not impact
any other the other sub-watersheds within the City of London, but will impact the Thames
River.
5. What larger watershed are all of these sub-watersheds a part of?
- The Thames River Watershed
6. In your own words, define ‘watershed’.
-
A watershed is an area that drains into a river, creek or lake. All watersheds are connected
to a larger area, draining all of their collected water.
7. What creates the divide between each watershed?
-
The natural landscape (slope) as water will always pick the path of least resistance.
8. What is a major factor in the creation of storm sewers in the City?
-
Stormwater must be managed to reduce the risk of flooding in the City.
Since we cover the ground with impermeable surfaces which does not allow water to be
absorbed into the ground we must find an alternative way to move stormwater, this is
why we need storm sewers.
9. A) In which sub-watershed do you live?
B) Where does this water flow to?
10. A) In which sub-watershed is your high school?
B) Where does this water flow to?
- The Thames River
11. What types of chemicals can pollute storm water?
- Salt
- Fertilizer
- Pesticides
- Pain
- Oil and Grease
- Gas
- Litter
- Cigarette butts
12. What are the sources of these chemicals?
-
The residents of the City of London
13. What can we do to reduce this pollution?
- Educate each other on the importance of keeping stormwater clean and encourage
change within your community.
Environmental Chemistry Introductory Thinking Scenarios:
1. Ms Thompson’s car is leaking oil badly. She drives it to school to have the automotive
department have a look. The car is parked outside on the west side of the school for the
whole day leaking oil until Mr Noakes has a chance to look at it. It rains all afternoon and the
leaking oil and gas run into a storm sewer in the parking lot. Where does it go and what will
the environmental impacts be?
2. Your parents have decided to close their salt-water pool early and drain the pool water
directly into the storm sewer outside your house. What impact will this have on the
environment, where will this water end up?
3. In the spring many home owners fertilize their lawns. When it rains and runs into the storm
sewers, where does it go and what are the environmental impacts?
4. This winter, your grandma was coming to visit, so your parents salted the whole driveway to
make sure that she wouldn’t slip. The salt melted all of the ice on your driveway, then what
happens to the melted snow and ice? What are the environmental impacts?
5. Attach a separate piece of paper that lists INTUs (I Need To Understand) for further
information you would want in order to properly answer the above questions.