By Wenran Fan, Yongjie Ji, and Wendong Zhang
A large region of low-to-no-oxygen zone—a hypoxic zone—forms every summer over the past three decades in the Gulf of Mexico, largely due to excessive nutrient runoff from states located within the upper Mississippi River Basin, including Iowa (Scavia et al. 2017; Rabalais and Turner 2019; Bianchi et al. 2010; Jones et al. 2018). Moreover, the excessive nutrients in local rivers and lakes results in the deterioration of water quality conditions within Iowa's water bodies. One of the emerging concerns pertains to the occurrence of harmful algal blooms (HABs), which pose health risks to individuals engaged in recreational activities within water bodies. Over the past two decades, the Center for Agricultural and Rural Development has undertaken numerous household surveys, funded by the US Environmental Protection Agency (EPA) and the Iowa Department of Natural Resources (DNR), with the aim of understanding the utilization of in-state lake recreational resources by Iowans, as well as the impact of water quality conditions on respondents’ choices of recreational destinations. Building upon the support provided by the Iowa Nutrient Reduction Center and the United States Geological Survey (USGS), we conducted a survey specifically designed to enhance our comprehension of lake recreation usage among households from underrepresented communities that were previously overlooked in earlier surveys.
History of the Iowa Lakes Project
CARD has developed a dedicated website portal (http://www.card.iastate.edu/lakes/) to provide a comprehensive summary of the research conducted over the past two decades. This portal serves as a valuable resource for recreational users, as well as the general public, facilitating convenient access to previous survey questionnaires and project reports. Furthermore, the portal incorporates an interactive section that allows users to explore a concise overview of popular on-site recreational activities, travel patterns of recreationists, and the economic impacts associated with specific lakes.
The 2021 Iowa Lakes Survey focusing on underrepresented Iowans
The historical Iowa Lakes Surveys employed a random assignment method to select statewide representatives. The 2019 survey combined samples from previous rounds of surveys and added new households that had not previously participated in the Iowa Lakes Survey. However, an important limitation of this statewide representative survey is its tendency to underrepresent younger, less educated, and lower-income Iowans. To address this issue, we conducted a study in 2021 to provide a crucial update regarding the use of lakes by underrepresented households in Iowa and those households’ attitudes toward water quality measures and economic development. The 2021 study aimed to bridge the gap by specifically focusing on underrepresented groups, ensuring a more comprehensive understanding of their utilization of lake resources and the factors influencing their engagement.
The 2021 survey targeted 3,000 Iowans residing in underrepresented communities. Figure 1(a) provides a map of Iowa where block groups with a darker shade indicate higher proportions of households earning $25,000 or less annually; and, figure 1(b) displays block groups with a higher percentage of non-white residents. The survey utilized a return sample of 388 Iowa residents from block groups that exhibited relatively low representation in previous rounds of surveys. These block groups were characterized by higher percentages of non-white population and more low-income households or rural households. The 2021 survey achieved a 14.2% response rate, with responses obtained from 2724 deliverable addresses. Table 1 presents a comparison of key demographics between the 2019 survey and the 2021 survey, along with reference information from the 2020 five-year estimates (2016–2020) obtained from the American Community Survey (ACS). Figure 1(c) illustrates the distribution of respondents in the 2021 survey. Analysis reveals that the 2021 survey sample encompassed a higher percentage of young respondents, a larger proportion of female respondents compared to the 2019 survey, and a higher number of unemployed respondents compared to ACS data.
Less recreation participation and use of lakes
Respondents to the 2021 survey displayed significantly lower levels of participation and recreational use of lakes compared to previous findings. Data from the 2019 survey show that 60% or respondents reported at least one single-day trip or overnight trip, with the average number of single-day trips and overnight trips being 7.8, and 2.13, respectively. However, in 2021, only 34% of survey respondents reported at least one single-day trip or overnight trip, with the average number of single-day trips and overnight trips being only 2.7 and 0.28, respectively.
| Variables | 2021 Survey | 2019 Survey | 2020 ACS |
|---|---|---|---|
| Age: % <35 | 17.4 | 7 | 27.4 |
| Age: % >60 | 52.3 | 37.4 | 29.8 |
| Gender: % Female | 43.6 | 35.7 | 50.3 |
| Residency: % Less than 10 years | 15 | 4.4 | N/A |
| Residency: % 10-19 years | 11 | 5.3 | N/A |
| Residency: % 20 or more years | 74.1 | 90.5 | N/A |
| Education: % college degree or above | 66.3 | 51.2 | 29.3 |
| Education: % high school or less | 11 | 21 | 38.3 |
| Employment: % Employed | 66.8 | 57.6 | 80.4 |
| Employment: % Unemployed | 8.6 | 1.9 | 2.5 |
| Employment: % Retired | 23 | 40 | 17.0* |
| Household Income: % <$25K | 9.9 | 9.5 | 9.4 |
| Household Income: % $25-50K | 15.9 | 19.2 | 17.8 |
| Household Income: % $50-100K | 33.8 | 42.1 | 36.9 |
| Household Income: % $100-150K | 19.2 | 18.7 | 21.0 |
| Household Income: % >$150K | 21.2 | 10.5 | 14.8 |
Great overlap in popular lake rankings
Table 2 presents the top 10 most popular lakes based on the findings of the 2021 survey. Among these lakes, Grays Lake stands out as the most frequently visited lake for both single-day trips and total trips. Additionally, Lost Grove Lake holds the top position as the most visited lake for overnight trips. Interestingly, there is a significant overlap in the list of the most popular lakes between the 2019 and 2021 surveys, indicating consistent preferences among respondents over time.
| Rank | Total visits | (2019 Ranks) | Single day visits | Overnight visits |
|---|---|---|---|---|
| 1 | Grays Lake | 6 | Grays Lake | Lost Grove Lake |
| 2 | Saylorville Reservoir | 2 | Saylorville Reservoir | West Okoboji Lake |
| 3 | West Okoboji Lake | N/A | Easter Lake | Lake Macbride |
| 4 | Lost Grove Lake | 10 | Blue Heron Lake | Clear Lake |
| 5 | Easter Lake | N/A | Big Creek Lake | North Twin Lake* |
| 6 | Blue Heron Lake | N/A | West Okoboji Lake | East Okoboji Lake* |
| 7 | Clear Lake | 1 | Coralville Reservoir | Big Spirit Lake* |
| 8 | Lake Macbride | 5 | Red Rock Reservoir* | Rathbun Reservoir* |
| 9 | Big Creek Lake | 7 | Clear Lake | Lake Cornelia* |
| 10 | Coralville Reservoir | 4 | East Okoboji Lake* | Lacey Keosauqua Park Lake* |
Shared on-site recreation activities and main recreation season
The popular recreational activities engaged in by respondents in 2021 were very similar to the 2019 survey (figure 2). The top three activities reported by respondents in 2021 were relaxing/picnicking, nature/wildlife watching, and trail use. However, there were noticeable differences compared to the 2019 results. Specifically, respondents in 2021 demonstrated a higher inclination towards trail use and a lower preference for fishing compared to their counterparts in 2019. Additionally, when considering the preferred recreational season, respondents in 2021 also displayed a tendency to visit lakes during the summer months, specifically June, July, and August. This trend indicates a consistent preference for summer as the primary time for engaging in lake-related recreational activities among the surveyed individuals.
Water quality is consistently the #1 factor for recreational decisions
Similar to the 2019 survey, respondents in 2021 also prioritized water quality as the most significant factor when selecting a lake destination, as illustrated in figure 3. Proximity and park facilities hold the second and third positions, respectively, while town activities and other factors are considered to be less important. The overall ranking of these factors remains consistent across the survey years, indicating a stable pattern of preferences among respondents.
DNR website is the default site for water quality information
The majority of visitors to Iowa lakes primarily relied on Facebook to obtain information about lakes, while they utilized the DNR website specifically to check water quality information. Approximately 8% of respondents indicated that they used the DNR website to find information about Iowa lakes, while 70% of respondents checked the DNR website when seeking water quality information. These figures differ from the 2019 survey results, which reported numbers of 47% and 83%, respectively.
Divergent views on pollution sources
In the 2019 survey, respondents identified agricultural runoff as the most concerning source of pollutants for Iowa lakes. However, in the 2021 survey, respondents expressed almost equal levels of concern regarding various sources, including livestock manure, urban runoff, trash, and oil or waste. This indicates a shift in the perceived importance of different pollutant sources among the 2021 respondents compared to those surveyed in 2019.
Emerging issues with HABs
The 2021 survey included questions regarding respondents' perceptions of HABs in Iowa lakes. Similar to the 2019 survey, approximately 59% of respondents indicated that they had heard of HABs. Furthermore, 31% of respondents reported observing a large algal bloom during their lake visits in 2021. In response to the presence of HABs, about 40% of the 2021 respondents chose to stop their planned water activities or relocate to another area, while 60% opted to continue with their planned activities. These figures demonstrate a notable difference compared to the 2019 survey, which reported percentages of 40% and 15%, respectively, for respondents who ceased activities or continued despite the presence of HABs.
Conclusion
In summary, this survey provides valuable insights into the utilization of lake recreation resources among underrepresented communities in Iowa. The findings indicate a lower level of lake resource usage among these communities, which prompts us to reconsider how future surveys can be adjusted to ensure better representation of the general population of Iowa. Furthermore, integrating these results with previous survey findings allows for improved analysis of Iowan's visitation patterns to in-state lake resources and facilitates more accurate benefit/welfare analysis of policy-induced water quality changes in individual lakes or a set of lakes.
References
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Bianchi, T.S., S.F. DiMarco, J.H. Cowan Jr, R.D. Hetland, P. Chapman, J.W. Day, and M.A. Allison. 2010. "The Science of Hypoxia in the Northern Gulf of Mexico: A Review." Science of the Total Environment 408(7): 1471–1484. https://doi.org/10.1016/j.scitotenv.2009.11.047
Jones, C.S., J.K. Nielsen, K.E. Schilling, and L.J. Weber. 2018. "Iowa Stream Nitrate and the Gulf of Mexico. " PloS One 13(4): e0195930. https://doi.org/10.1371/journal.pone.0195930
Rabalais, N.N., and R.E. Turner. 2019. "Gulf of Mexico Hypoxia: Past, Present, and Future." Limnology and Oceanography Bulletin 28(4): 117–124. https://doi.org/10.1002/lob.10351
Scavia, D., I. Bertani, D.R. Obenour, R.E. Turner, D.R. Forrest, and A. Katin. 2017. "Ensemble Modeling Informs Hypoxia Management in the Northern Gulf of Mexico. " Proceedings of the National Academy of Sciences 114(33): 8823–8828. https://doi.org/10.1073/pnas.1705293114.
Suggested citation
Fan, W., Y. Ji, and W. Zhang. 2023. "New Survey Targeting Underrepresented Iowans Reveals Limited Usage of Lake Resources." Agricultural Policy Review Spring 2023. Center for Agricultural and Rural Development, Iowa State University.