Assessing University Student Responses to Rain Gardens

Rain Gardens present a low impact solution to flooding, pollution and habitat loss of bees, migrating birds and butterflies as caused by development on college campuses.

Introduction

 

 


As impervious surfaces increase with Rutgers university development, rain gardens present a low impact solution for using the natural water cycle to collect storm water and mitigate surface runoff. Storm water runoff is problematic because the rainfall which lands upon roadways, parking lots, rooftops and other urban spaces is not absorbed into the earth, but rather, flows into nearby watersheds through gutters and outfalls, leading to problems like flooding and bank erosion in the process (Watershed Forestry, 2008). Existing literature provides a solid foundation for public education surrounding rain gardens, which employ a natural hydrologic process in order to reduce the peak flow of storm water runoff. If done correctly, these gardens can provide habitat for local species, like bees and migrating butterflies, but can also reduce non-point source pollution. The process, as captured in a recent Earth Science Journal (2016) starts with runoff, “Passing through the bio retention unit, the pollutants in the runoff can be removed through sedimentation, filtration, sorption on mulch and soil layers, plant uptake, and biodegradation by soil microorganism” (Li, 2016, 2).
By collecting pollutants that would otherwise be carried into wastewater treatment facilities, rain gardens have noted human health benefits. Not only do rain gardens slow and treat storm water runoff, but they are also a way to eliminate Combined Sewage Overflow contributions, by collecting storm water and filtering it for evapotranspiration (Ingwersen et al, 2015). Existing literature (2015) outlines the danger of Combined Sewage Overflow; “When a combined sewer system reaches its containment capacity and overflows, such as during heavy storms, the excess sewage is dumped untreated into nearby water bodies” (Ingwersen et al, 1342). Since rain gardens can be installed to eliminate CSO incidents, they offer the potential improve the quality of nearby bodies of water as well.


By examining the literature available this research, we first had to consider

1) How successful have other universities and communities been with rain garden projects?

2) What obstacles (financial, political, upkeep, etc.) did they face while implementing the gardens?

 

Research at Villanova University has demonstrated the long-term effectiveness of campus rain gardens in both collecting storm water and removing orthophosphate, the “bioavailable form of phosphorus” (PO34-P) through collection and sorption (Kolmos and Traver, 2012). The term bioavailable refers to plant life, such as algae, which can receive too much nutrients from Phosphorus (P), thereby taking up Oxygen needed by other species. Although ortho-phosphates occur naturally, they are added to water bodies through human activity including partially treated or untreated sewage; agricultural runoff, and fertilizer use (Minnesota State). This is where rain gardens such as the Bioinfiltration Traffic Island site at Villanova University come in.
As researchers at the Villanova department for civil and environmental engineering (Kolmos and Traver) explain, “The primary mechanisms by which P is removed from infiltrated storm water are precipitation and chemical sorption of PO34 −P to soil surfaces through reactions with iron, aluminum, or calcium” (2012, 991). Their research collected subsurface water samples of orthophosphate and used lysimeters to measure the subsurface removal of PO43−P with infiltration depth (2012). Measuring the volume of precipitation as it entered and left the garden across 222 storms, their data was first able to substantiate the rain garden as an effective apparatus of rain water management throughout the seven year monitoring period and found that, “The median orthophosphate concentration “decreased from 0.21–0.25  mg/L in the ponded water to 0.03  mg/L in the pore water at the bottom of the infiltration bed” (Kolmos and Traver, 2012, 994).
Moreover, other campuses, like Mercer University in Macon Georgia, have utilized rain gardens not only for functionality during storms, but for the aesthetic quality they can bring to campus. University business reviews (2014) cite the 100-foot-long rain garden, with various depths, as a project able to mitigate some of the damage caused by developments of tailgating area parking lots, while freeing up green space for walkways near the stadium (L.W). While existing literature on rain gardens detail the implementation process and best Green Infrastructure practices, this research aims to provide the perspectives of students at Rutgers University on raingardens and observe potential responses of rain gardens on desire paths, in order to supplement local landscaping recommendations.

 

This research sought to answer;
1. Does the location and visual appeal of rain gardens affect their success? To what extent do community residents see the value of installing rain gardens around Cook/ Douglass campus? And 2. What are some obstacles (financial, upkeep, etc.) that Rutgers maintenance staff and Rutgers Gardens staff have experienced and continue to experience by implementing rain gardens around Cook/ Douglass campus?

 


Method


This research utilized an online survey (Qualtrics) to inquire about Rutgers students’ perceptions and beliefs regarding rain gardens (Table 1). Rutgers Students were recruited through snowball sampling for the distribution of the Qualtrics survey link amongst acquaintances in the marine, biological, environmental and political science departments across Cook, Douglass, College Ave, Livingston and Busch campuses Upon opening the survey, all participants read and consented to a consent form in order to participate in the survey. If consent was declined, the survey closed. The survey included a description of raingardens as well.

 

Table 1.

Online survey questions on perceptions and beliefs of rain gardens
1 Do you know what a rain garden is?
2a Have you ever seen a rain garden before?
2b What campus do you spend most of your time on?
3 What school do you belong to at Rutgers?
4 Are gardens/ landscaping areas a common obstacle that you encounter on your way to class
5 On a scale of 1-10, how much of a problem would you say that muddy areas are on your walk to class?

6 On a scale of 1-10, how often do you notice and/or enjoy seeing gardens/landscaping around campus?

7 How beneficial do you think rain gardens are in helping the environment? (1 = not helpful at all, 10 = extremely helpful)
8 In what areas do you think rain gardens help the environment? Water filtration, creates habitat for wildlife, collects pollution, prevents soil erosion, creates habitat for native plant species, rain gardens don’t help the environment (Check all that apply)
9 How important is it for there to be habitats around campus for local wildlife? (Bees,
migrating birds, butterflies/ dragonflies, etc.) (1= I don’t care about wildlife around
campus, 10= It’s very important for there to be places around campus for wildlife)
10 Which rain garden would you enjoy seeing more around campus? (2 example illustrations)

Additionally, this research gathered qualitative data through interviews of Cook/Douglas Rutgers gardens staff interviews to gather information regarding rain garden landscaping (n=2). Interviewees were contacted by email for participation, and were given the option to either answer a series of open-ended questions through email format or through in person interviews (Table 2). A consent form was administered at the beginning of the online interview, and before the start of the in- person interview, the interviewee was read an oral consent form.

 


Table 2:

Email and in- person interview questions on rain garden maintenance


1 What are the obstacles to having rain gardens on campus?
2 Where does funding come from for grounds maintenance and landscaping and how much is allotted?
3 How much do you spend on landscaping, how often do you have to upkeep?
4 Do you have a sense of what is essential to keep rain gardens going?
5 Do you see any obvious benefits from existing rain gardens around campus?
6 Have you had experience with rain gardens in the past?
7 Would it make it easier to collect garbage/pollution around campus if it was collected in rain gardens?
8 How much would rain gardens ease collection of trash around campus?

 

Finally, an observational study was conducted at a test rain garden outside of the Cook Douglass Lecture Building in order to gather data on student behavior and responses to potential rain gardens on the Cook/Douglass campus. With permission from Patrick Harrity at Rutgers Facilities, a small area on a popular desire path approaching the CDL building was sectioned off and labeled as a rain garden. The mock garden was then monitored to record the levels of disruption as incurred from students during class day traffic from Wednesday April 19 to Friday April 21. Seven observations were noted; Wednesday from 8-8:30 am ,11-11:30 am, 6:45-7:15 pm, Thursday from 10:30-11 am 12-12:30 pm and 2-2:20 pm and Friday morning from Friday: 10-10:20.

 

Results


The student survey garnered 56 responses, of which 53 consented with the survey. However, Qualtrics recorded a small dropout rate into the first question, reducing the total of usable responses to 46. 1 participant did not answer question 5 out of the survey, and dropped out after question 8. Therefore, for questions 5, 9 and 10 of the survey n=45 (Figure 1).


Firstly, the survey results indicated a majority of Rutgers students reported being familiar with rain gardens (Figure 2). 58.7 percent selected yes, 15.2 percent selected no, and 26.1 percent were not sure. However, less than half of students, 43.48 percent, reported being confident that they had ever seen a rain garden (Figure 3). 89.9 percent of the 46 students surveyed spent most of their time on either Cook Douglas and College Avenue campus; with over half (55.6 percent) on Cook/Douglass Campus, and 33.3 percent on College Avenue. Roughly 10 percent resided on Livingston or Busch campus, creating some levels of limitation within the university- wide survey (Figure 4). An equal number of subjects reported belonging to the School of Environmental and Biological Sciences, and the School of Arts and Sciences at 46.7 percent. A much smaller percent of students reported belonging to the Mason Gross School of the Arts and the Rutgers School of Engineering (Figure 5).


Overall, a low percentage (23.9 percent) of students surveyed answered “yes” to landscaping and gardens being a problem on their walks to class, where students who answered “no” comprised the larger percentile (Figure 6). The 1-10 scale used to assess subject’s perception regarding how often muddy areas impeded their walks to class generated a mean of 5.98, with a variance of 2.32 (Figure 7). The data set of results for this scale were bimodal; the modes were 6 and 8, both at 17.4 percent. The graph below includes the choice count of survey participants for each option, where the answers spanned the full range of the field.

1-10 answer field


Additionally, the results indicated a strong response of student’s noticing landscaping projects throughout campus (Figure 8). A combined 80.4 percent of the surveyed population reported noticing/and or enjoying rain gardens around campus most or all of the time, with another 17.4 of students noticing/ and or enjoying rain gardens sometimes or about half of the time, while on campus. A small percentage (2.2 percent) of students reported never noticing/ and or enjoying rain gardens (Figure 8). The other 1-10 scale, recording how beneficial students’ perceived rain gardens to be for the environment generated a mean of 8.39 with a standard deviation of 1.6 (Figure 9). Scores ranged from 4 to 10, and the mode in the data was 10, totaling 40 percent of user responses.


Almost every participant in the survey reported that rain gardens help the environment through water infiltration (93.5 percent). The second most popular choice was that rain gardens create habitat for native plant species at 80.4 percent, followed closely by preventing soil erosion and providing habitat for local wildlife (Figure 10). Exactly half of the participants chose that rain gardens helped the environment by collecting pollution and 2 percent reported that rain gardens don’t help the environment at all (Figure 10). When prompted about how important local habitats were for affected wildlife, the average survey response measured 8.2 on the 1-10 scale, with a standard deviation of 2.3 (Figure 11). Answers ranged from 2 to 10, with 10 comprising 48.9 percent of answers (mode=10). Finally, students preferred the first rain garden illustration to the second one by a ratio of 36:10.

 


Next, both Rutgers Gardens interviews provided qualitative data regarding measures of rain garden upkeep, cost and planning. There were consistencies between both the director and staff/master gardener on maintenance practices. Both interviewees cited pruning in the fall as a major part of the minimal upkeep process. Neither of the interviewees found trash collection to be a factor in their rain gardens. Both Bruce Crawford and Stacey Approvato agreed that the obvious benefits of rain gardens included ground water recharge, runoff management and reduction of non-point source pollution.

 

 

Finally, The observation of the mock rain garden experiment uncovered very minimal disturbance.
 

Table 3
Observation Shift Results


1 No disturbances
2 Rope loosened, No observed disturbances
3 No disturbances, visible student interest
4 No disturbances, visible student interest
5 Visible student interest, avoided accidental impact
6 Visible student interest, avoided accidental impact
7 No disturbances

The mock garden remained completely in-tact throughout the duration of the experiment, with the only possible disturbance occurring between 8:30 and 11:00 am on day 1. While there were no observed disturbances during any observation shift, the garden generated student interest on 57 percent of the recorded experiment periods. Student interest is characterized by act of either 1) pausing to read the mock rain garden sign, 2) returning to the garden to examine it, or 3) discussing the mock garden with peers. Finally, the mock rain garden was almost disturbed on two occasions, when distracted pedestrians on cell phones passed by the vicinity. During both incidents, a collision was averted.


Finally, both Rutgers Gardens interviews provided qualitative data regarding measures of rain garden upkeep, cost and planning. There were consistencies between both the director and staff/master gardener on maintenance practices. Both interviewees cited pruning in the fall as a major part of the minimal upkeep process. Neither of the interviewees found trash collection to be a factor in their rain gardens, but advised that curbside construction might be best for this purpose. Both Bruce Crawford and Stacey Approvato agreed that the obvious benefits of rain gardens included ground water recharge, runoff management and reduction of non-point source pollution.

 

Discussion


The results of the rain garden survey designed to measure Rutgers students’ perception indicated that, likely, a majority of Rutgers students are confident regarding their basic knowledge of a rain garden, despite fewer having seen one before. Although the veracity of the subjects’ self- reported data may be challenging to assess, this finding may also indicate some level of general knowledge of rain gardens’ existence in the Rutgers student body.
Although Rutgers University New Brunswick has 5.49 times as many students enrolled in the School of Arts and Sciences as the School of Environmental and Biological Sciences, the equal percentage of survey participants from both schools can potentially be attributed to the use of snowball sampling where 5/6ths of recruiters were in SEBS. The School of Engineering has a similar enrollment of students at 3,455 and Mason Gross the smallest, at 1,037 enrolled students. Although the groups were not proportionately represented (Our schools and Colleges, 2017) the schools represented have many courses on Cook Douglass campus, positioning Cook Douglass as a solid starting point for future rain garden implementations.
The survey data indicated that Rutgers students are generally very receptive of additional landscaping projects on campus. The survey demonstrated that currently, most Rutgers students do not believe campus landscaping projects obstruct their walks to class; less than 24 percent. Instead, the survey found that over 80 percent of students notice or enjoy landscaping projects around campus. The mean of the next survey question, demonstrates that students, on average view muddy areas as somewhat obstructive on their walks to class (5.98). Moreover, the two modes, 6 and 8, suggests most participants found muddy areas to be a problem more often than not. Also with a high mean, and mode of 10, the survey indicates that students surveyed strongly viewed rain gardens as beneficial for the environment.


Beside the answer that rain gardens do not help the environment, student answers regarding the benefits of rain gardens were largely rather close, with little variation. The notable exception was found for the pollution collection answer, only chosen by 50 percent of subjects. This represents a divergence from expert opinions on the desired functions of rain gardens, as means of reducing runoff pollution. Because almost half of students, selected the maximum value regarding the importance of habitat for local or migrating species, and the data generated a mean value of 8.2, the overall findings suggest that Rutgers students endorse one of the primary functions of rain gardens on campus. Lastly, the survey reflects a student preference for bright, diverse looking gardens, as opposed to more compact green ones, outlined by rocks. This look can be achieved through certain landscaping practices as indicated in the interview section of our method.

 


The interview with Stacy Approvato cemented the significance of native plants for optimal performance outcomes. Approvato explained how the deeper root system of native plants are best for water absorption, since they hold moisture in the soil. Native plants can handle periodic inundation, and work in tandem with the natural conditions of the ecoregion where the rain garden is installed. (“Design and Construction”, 2009). She also mentioned the benefits of perennial plants, stating, “Beside pruning in the fall, you can make sure your same plants come back in the Spring. This is what we tell homeowners too, who don’t want to deal with upkeep” (S. Approvato, personal interview, April 2017). Using native perennial plants, with deep root systems, are cost effective due to their sorption performance and ecologically balanced pest control , but also time effective as upkeep is kept minimal.
In addition to pruning, Bruce Crawford also mentioned weeding as an integral part of upkeep. Regarding Crawford’s (2017) figure regarding maintenance costs and new planting, the allocation of $3,000 annually for the campus rain garden is a relatively inexpensive for Rutgers, when considering remediation costs incurred from damage due to flooding and erosion on campus. Bruce accounted for long-term maintained as well, stating that, “If the water comes from a road or parking area, small particulate matter, such as sand and silt will accumulate on the bottom which will need to be removed every few years, based up accumulation amounts” (personal interview, April 2017).

 


Finally, the mock rain garden experiment illustrated that rain gardens could generate curiosity on campus, without being physically tampered with. This was especially notable considering the placement of the garden, which obstructed a Cook Campus desire path on the way to a multi- classroom lecture building. Since most Rutgers rain gardens, such as the one neighboring Blake Hall are hidden from any pathways, future research regarding student interactions with rain gardens might include the accidental collisions when building in more trafficked areas. This research recognizes that the test was only performed in one location, yet demonstrates potential for Rutgers student involvement and cooperation on future rain garden projects.

 


The rain garden survey and mock- garden experiment both convey that students are supportive of the idea of more rain gardens throughout Rutgers University New Brunswick. The mock garden experiment also denotes that the gardens would encounter little interference on campus. Finally, interviews also demonstrate that there are ways to reduce costs and upkeep involved.

Appendix

Figure 1
Consent
# Answer % Count
1 I agree 96.36% 53
2 I disagree 3.64% 2
Total 100% 55

Figure 2
Do you know what a rain garden is?
Answer % Count
Yes 58.70% 27
Maybe 15.22% 7
No 26.09% 12
Total 100% 46

Figure 3
Have you ever seen a rain garden?
Answer % Count
Yes 43.48% 20
Maybe 30.43% 14
No 26.09% 12
Total 100% 46

Figure 4
Answer % Count
College Avenue 34.78% 16
Cook/ Douglass 54.35% 25
Busch 2.17% 1
Livingston 8.70% 4
Total 100% 46

Figure 5
Answer % Count
School Environmental and Biological Sciences 46.7 21
School of Arts and sciences 46.7 21
Mason Gross 4.4 2
School of Engineering 2.4 1

Figure 6
Answer % Count
Yes 23.91% 11
Sometimes 34.78% 16
No 41.30% 19
Total 100% 46

Figure 7
Field Minimum Maximum Mean Std Deviation Variance Count
Scale 0.00 10.00 5.98 2.32 5.37 46
Figure 8
Answer % Count
Always 41.30% 19
Most of the time 39.13% 18
About half the time 4.35% 2
Sometimes 13.04% 6
Never 2.17% 1
Total 100% 46

Figure 9
Field Minimum Maximum Mean Std Deviation Variance Count
Scale 4.00 10.00 8.39 1.61 2.59 46

Figure 10
Answer % Count
Water filtration 93.48% 43
Creates habitat for wildlife 76.09% 35
Collects pollution 50.00% 23
Prevents soil erosion 78.26% 36
Creates habitat for native plant species 80.43% 37
Rain gardens don’t help the environment 2.17% 1
Total 100% 46

Figure 11
Field Minimum Maximum Mean Std Deviation Variance Count
Scale 2.00 10.00 8.24 2.30 5.30 45