1.0 Introduction
Since the expansion of the Clean Water Act (CWA) in 1972, the federal
protection of wetlands and rivers in the United States has been governed
by the debated and fluid definition of the “waters of the United
States” (WOTUS). Wetlands are crucial components of terrestrial
landscapes, providing numerous benefits that include biological habitat,
floodwater attenuation, biogeochemical processing, and sediment
retention (Acreman & Holden, 2013; Capps et al., 2014; Cheng & Basu,
2017; Lane et al., 2018). Despite these widely recognized benefits,
wetlands have been disregarded, destroyed, and filled for economic
benefit over the past 200 years (e.g., Dahl, 1990; Davidson, 2014;
Golden et al., 2019; Hey & Philippi, 1995; Van Meter & Basu, 2015),
resulting in subsequent losses of ecosystem services (e.g., Zedler,
2003). Under the CWA, jurisdiction waters (WOTUS) require permits for
pollutant discharges, dredging, or filling, while non-jurisdictional
waters are afforded no such protections at the federal level. The extent
of WOTUS has been ill-defined for more than 50 years, evolving through a
series of legal cases and iterative rulemaking that have yielded an
operational definition (Walsh & Ward, 2019; Walsh and Ward; In Review).
Unlike laws that require legislative initiative, the definition of WOTUS
is embedded in the rulemaking process of the executive branch, leaving
operational definitions to be established by regulatory agencies (in
this case, the USEPA and USACE). Through many high-profile judicial
decisions and executive revisions, the extent of WOTUS has seen
continual evolution and interpretation (Walsh & Ward, In Review).
The last decade has seen two redefinitions of WOTUS, resulting in
significant changes to the federal protection of wetlands in the US.
First, the 2015 Clean Water Rule (CWR) attempted to reconcile prior
Supreme Court rulings (United States v. Riverside Bayview Homes ,
1985; Solid Waste Agency of Northern Cook County v. USACE , 2001,Rapanos v. United States , 2006) into a clear-cut regulatory
framework that was both consistent and easily interpretable (USDOD and
USEPA, 2015). In addition to protecting intermittent and ephemeral river
systems, the CWR classified adjacent waters and wetlands into
jurisdictional categories using buffer distances from other protected
waters. Leaving room for scientific interpretation, the CWR also
codified the “significant nexus test”, mentioned in Solid Waste
Agency of Northern Cook County v. U.S. Army Corps of Engineers (2001)
and reaffirmed in Justice Kennedy’s concurring opinion in Rapanos
v. United States (2006). Under the significant nexus test, protections
are extended to adjacent water and wetlands on a case-by-case basis if
they “significantly affect the chemical, physical, and biological
integrity” of adjacent navigable waters, taken alone or in combination
with similarly situated waters (Rapanos v. United States , 2006).
In response to these changes to the WOTUS definition, 31 states and a
variety of other plaintiffs pursued legal action to oppose the
enforcement of the CWR (e.g., Georgia v. Pruitt , 2018;North Dakota v. USEPA , 2015; Texas v. USEPA , 2018; USDOD
and USEPA, 2019). After litigation and numerous preliminary injunctions,
the CWR remained enforceable in only 22 US states, including New York
(CRS, 2019). A new rulemaking process, intended to revise the CWR, was
initiated via executive order in 2017 (Exec. Order No. 13778, 2017).
In 2019, the CWR was repealed and by April of 2020 replaced by the
Navigable Waters Protection Rule (NWPR). To promote economic growth and
development and to reduce regulatory uncertainty, the NWPR sought to
redefine the legal term ‘navigable waters’ consistent with the opinion
authored by Scalia et al. in Rapanos v. United States (2006). The
NWPR restricted federal protections to waters that contribute flow to a
traditionally navigable waterway or sea in a typical year (USDOD and
USEPA, 2020). The updated rule also eliminated the significant nexus
test, requiring wetlands to receive continuous surface flow from other
jurisdictional waters to be considered jurisdictional. This redefinition
of WOTUS under the NWPR was vacated by Pasqua Yaqui Tribe v. USEPA
(2021 ). With the CWR repealed and NWPR struck down, federal wetland
protections in the US have presently reverted to the regulations
codified by the USEPA and USACE in 1986 (USDOD, 1986), though new
rulemaking has been initiated (USDOD and USEPA, 2021).
Given the recency and fluidity of ongoing revisions to US federal water
policy, few studies have assessed how the evolving definitions of WOTUS
have altered the protection of wetlands (Sullivan et al., 2020). While a
limited number of past studies have considered the protection of
wetlands at the watershed scale (Walsh & Ward, 2019; Meyer &
Robertson, 2019), additional work is still needed to characterize the
complex implications of these changes to federal water policy, as the
services provided by wetlands are non-uniform and vary considerably as a
function of spatial location (Cohen et al., 2016; Lane et al., 2022;
Marton et al., 2015) and size (Cheng & Basu, 2017; Ghermandi et al.,
2010). This need is even more pressing given that the USEPA and USACE
have indicated that a WOTUS revision will occur in the near future
(USEPA, 2021). Thus, our objective in this study is to document how
changes to the legal definition of WOTUS under the CWR and NWPR alter
which wetlands are protected as a function of their landscape position
and size. To achieve this objective, we use the wetland-dense state of
New York (NYS) as a case study to demonstrate how changing regulatory
language can yield patterns of protection that are biased against
particular types of wetlands. Through regional analysis, we contribute
to the evolving discourse assessing the implications of WOTUS definition
revisions for wetland protections. We also provide additional discussion
to contextualize the controversial nature of federal wetland protection
and policy amongst numerous competing interests.