Group 2 Freeway 6 Wetland 12-21-2011

8/10/2019 Group 2 Freeway 6 Wetland 12-21-2011

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Highway sustainable design management-

Case study of national highway No.6

Introduction

Wetland has been used for solving the water problems nowadays. For example, it

could be used for treating the wastewater, decreasing the stormwater runoff, and to

improve the quality of the stormwater runoff. It can be combined with the regulations

in Greenroads rating system to get some credits on it. Also wetland provides the

scenic view by the design of many kinds of plants, that’s related with the site

vegetation and the habitat restoration. Furthermore, the plants can absorb the CO2 that

helps to reduce the green house emission.

There are many cases that use wetland to achieve their goal for manage the waste

water, and under the good design it can all have great efficiency. For our project, we

propose to use the wetland as a kind of ecology pond, combine it with the highway

and connect it with the Greenroads rating system for the related credit, such as runoff

control and quality, site vegetation, habitat restoration, and scenic views. (not clear

yet?)

Background

National Highway No. 6 (also called Nantou Freeway) is a freeway between Wufeng,

Taichung and Puli, Nantou, and all of the main line was already open to traffic on

March 21, 2009. And so far, there are still some interchanges which are under

construction. (Reference?)

National highway No.6 was the first highway constructed according to ecological

highway in Taiwan. Thus, the highway was constructed following three objectives.

Firstly, it emphasized on traffic, safe, quality, cost and other functions. Secondly,

generation highway would increase technology and appearance. Thirdly, generation

needs to consider how to codependent with nature. National highway No.6 follows

Wu River, Nangang River and valley of Meisi. Therefore, the highway was

constructed with different attitudes and methods that respected the nature and reduced

impacts on whole ecosystem to implement the third generation. About 70% of

construction adopted elevated method. Besides, the highway bypassed two big bends

in order to avoid Jiujiu Feng natural preservation zone. As a result, mountain,

primeval forest and river along the highway are spectacular.

In this project, we will consider the sustainability of highway No. 6 through some of



the credits in Greenroads rating system.(not clear?) By this way to see if we can make

it more environmental friendly and adopt it to the Greenroads. (not clear?)



Greenroads rating system

At the Greenroads rating system, we propose design and manage part of highway,

(Not clear?) and get the following credit. The highway No. 6 at Ai Lan access road,

design an ecological pond. That’s the part we want to select and analyze for our

project.



EW-2 Runoff flow control

Our idea is that, to get this credit, first we have look up the weather information of the

area. By knowing the length and width of the road, we can calculate the runoff flow

quantity. And by using this data, we can design the grass ditch beside the road andcollect the rain water. The collected water will finally flow to the wetland (ecology

pond) for storage and be used to irrigate the plants in the wetland. (Use real values to

calculate.)



Like the graph, that rain water on the pavement can be drained to the ditch and flow

slowly in the grass ditch. Than it could be store at the ecology pond for treat the waterthere. (Need more explanations)

EW-3 Runoff quality

In the EW-3, we need to treat the water to certify the leve it set. Like the total

suspended solids concentrations needs to below 25 mg/L. Also need to treat the water

as much as posible to get more credit (90% of the volume will get the highest score).

By using the grass ditch, such us the subsurface flow system of wetland, can treat the

water well at this part. (How?) And the water will be flow to the ecology pond, such

as the free water surface system of the wetland, that will treat the water second time

(How?) for sure to get the credit of EW-3.



Subsurface flow system, SSF

free water surface system, FWS

EW-5 Site vegetation

Site vegetation also can be mentioned. While we use the grass ditch and the ecology

pond, the plants using can be chosen for satisfying the credit. In the EW-5, it is

considered to use non-invasive plant species and use native plant species only. (What

kinds of? Maybe they are difficult for you to specify.) So in this credit, we need to

find the native plants species to plant in the project. It also required that do not use

water to irrigate after the plant establishment period. According to this request, the

ditch for collecting the rain water can be also used for irrigation, and that will help us

to get this credit more easily.



EW-6 Habitat restoration

For this credit, we need to complete option A or B which are:

Option A – For projects required to mitigate habitat impacts through restorative

practices (3 points)

Implement a restoration/preservation plan that restores and/or preserves more area by 5% beyond what is required such that one of the following metrics below is met:

1. Total area of restored and/or preserved habitat equals or exceeds 105% of total

required mitigation area

2. Total restoration and/or restoration cost equals or exceeds 105% of total cost

required for restoration/preservation due to the roadway project

Option B For projects not required to mitigate habitat impacts through

restorative practices (3 points)

Conduct a biological assessment of the pre‐development condition of the project site

and surrounding ecosystem or watershed and implement a restoration plan that

includes all seven items below:

1. Restores an area equal to the total disturbed surface area of the roadway project.

2. States quantifiable goals regarding at least one of the performance metrics outlined

below.

3. Describes ecological design or engineering elements that are expected, with

reasonable professional certainty, to meet the goals stated above.

4. Lists responsible parties for restoration activities and subsequent monitoring

efforts.



5. Lists sources of funding for restoration activities and subsequent monitoring

efforts.

6. Completes restoration activities prior to the roadway facility opens to traffic,

ideally during project planning.

7. Is signed and approved by the responsible parties or the project ecologist.

In our project, we shall select option A, and for design the ecology pond that we can

get the credit in this section.

AE-8 Scenic views

When design the grass ditch and the ecology pond, we should include this credit and

consider the benefit from safety and the culture in that place. Also we can try to haveeducational and culture outreach from this indicator.

Conclusion

Since last time presentation, we are now focusing on the EN2 and EN3. (GRI？ The

goals? Then pursue them in your term project.) To design or manage for these

indicators, the rain water data is needed.

Month

Date

月

二月

三月

四月

五月

六月

七月

八月

九月

十

月

十

月

十二

月

1 - - - - - - - - 4.3 - - -

2 4.1 - - 2.7 - 9.2 - 0.1 5.5 - - -



3 7.4 - - 0.9 - 2.7 - - - - - -

4 - - - - - 0.3 - 4.6 44.6 - 3.4 -

5 - - - 7.6 - - - 11.9 - - 1.3 -

6 4.1 9.1 - 10.4 0.2 - 2.8 - - - 0.2 -

7 2.0 3.6 - - 0.9 - - - 1.5 - - -

8 8.7 - - 43.6 0.8 - - - 54.6 0.5 - -

9 - - 7.6 13.4 2.7 0.7 - 2.4 12.5 - - -

10 - - - - T 53.2 - - 2.3 - - -

11 0.2 - - - - 56.1 - 24.2 56.5 - - -

12 1.6 11.5 - - - 21.6 13.5 5.6 7.4 - 0.7 -

13 - 7.7 5.6 - - 80.1 38.5 - - - 13.4 -

14 - - - - - 117.6 - 7.4 - - 1.2 T

15 - 1.0 - 16.8 2.9 9.2 0.6 17.8 - - - 5.5

16 - 13.2 - 1.8 - - - - - - - 20.9

17 - 21.8 - - - - 1.3 7.4 - - - -

18 - 16.9 - 0.2 - - 0.1 11.2 5.2 - - -

19 - 31.4 - - - - - - 66.0 0.3 0.5 -

20 - 0.7 - - - - - - 0.5 - - -

21 - - - - - 39.5 37.1 - 2.8 1.3 - -

22 - 1.4 - 1.4 - 16.1 28.8 0.1 - - - -

23 - - - 44.3 105.6 12.6 21.4 9.0 - - - -

24 - - 4.2 0.5 - 18.1 1.0 12.0 34.0 - - -

25 5.7 T 5.2 - - 44.9 21.2 55.5 - - - 1.0

26 0.3 - - - - - 62.5 5.1 - - - -

27 - - - 0.8 0.2 24.5 125.5 1.8 - - - -

28 - - - 1.0 5.2 23.5 93.5 2.9 - - - -

29 - - 3.7 22.8 - - 10.6 30.9 - - -

30 - - 9.3 4.0 - 15.6 0.8 - - - -

31 - - - 0.1 13.1 - -

Total 34.1 118.3 22.6 158.4 145.3 529.9 463.5 203.5 328.6 2.1 20.7 27.4

Taichung total rain water in 2010

In the chart we can see that, the maximum rainfall is 117.6mm in one day, (which

place?) and we should design the wetland for adopting this data. Also according to

this data, we can design the depth (How?) of the grass ditch for our project.

For the runoff quality, TSS can be removed about 90% in the wetland system. That



helps us to get the credit in EW3. As the result, we will according the guideline of

wetland system, to find which size and type we should design for this indicator.

The division of our group will have one person focus on EW2, one focus on EW3.

And the last person will find the high way NO.6 information and data to adopt

these two indicators, also this can be used to another project for our concept.

Documents

Group 2 Freeway 6 Wetland 12-21-2011