Assessment of Wetland Restoration, Enhancement, and Creation Opportunities on Selected Metro

Properties

by Paul R. Adamus, Ph.D.

Adamus Resource Assessment, Inc. Corvallis, Oregon

adamus7@comcast.net

for Metro Parks and Greenspaces

Portland, Oregon

March 21, 2005

Contents 1. Introduction ................................................................................................................................. 3 2. Methods....................................................................................................................................... 5 3. Site Descriptions ......................................................................................................................... 6

3.1 Coffee Lake ........................................................................................................................... 6 3.2 Gales Creek south .................................................................................................................. 9 3.3 Madsen................................................................................................................................. 11 3.4 Munger................................................................................................................................. 13 3.5 Pigeon Lake ......................................................................................................................... 15 3.6 Weber Farms........................................................................................................................ 17 3.7 Wilsonville........................................................................................................................... 19 3.8 River Island.......................................................................................................................... 21

4. Conclusions ............................................................................................................................... 22 5. Literature Cited ......................................................................................................................... 24 Appendices (electronic data files):

HGM Function Assessment Data for Coffee Lake wetland HGM Function Assessment Data for Gales Creek wetland HGM Function Assessment Data for Madsen wetland HGM Function Assessment Data for Munger wetland HGM Function Assessment Data for Pigeon Lake wetland HGM Function Assessment Data for Weber Farms wetland HGM Function Assessment Data for Wilsonville wetland

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1. Introduction Background Metro Parks and Greenspaces (MPG) is considering the feasibility of establishing a wetland mitigation bank on its owned public properties. If such a bank were to be established, Metro could be allowed to sell mitigation credits after restoring wetlands that existed previously on such sites or in some instances, possibly by enhancing existing wetlands. After restoration of these sites is completed, Metro would sell mitigation credits from the bank to persons whose authorized activities have unavoidable adverse effects on wetlands elsewhere. The Metro mitigation bank would operate in a manner generally similar to other legally-approved mitigation banks in Oregon. Metro contracted for this report to partially examine the feasibility of a mitigation bank on eight MPG-owned properties. The report’s purpose is to assess the general suitability of these properties for wetland restoration, enhancement, and/or creation. Understanding these terms precisely is crucial, or state and federal wetland permitting agencies might not recognize any potentially-resulting requests for distribution of mitigation credits. Restoration Potential The Oregon Department of State Lands (ORS 141-085) defines restoration as:

“to reestablish wetland hydrology to a former wetland sufficient to support wetland characteristics.”

DSL further requires:

“plans for restoration projects shall include data substantiating that the site was formerly, but is not currently, a wetland”

To assess the likelihood a compensatory site will qualify for mitigation credit based on wetland restoration, the applicant must demonstrate that:

• The site currently does not meet formal jurisdictional criteria for wetland determinations, AND

• Previous changes in site hydrology which caused it to cease meeting wetland criteria can feasibly be reversed or otherwise corrected.

Thus, a site might qualify for restoration credit if it can be demonstrated that: (1) the site formerly was a wetland, AND

(2) the site no longer is a wetland, i.e., any of the following are true: a) hydrophytic vegetation no longer predominates as a result of hydrologic changes b) soil redoximorphic indicators no longer are present as a result of hydrologic changes, e.g., lowered water table, c) soils are no longer inundated or saturated for at least week during the early spring as a result of hydrologic changes. AND

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(3) measures undertaken by Metro to restore the hydrology of the site will reverse all of the above deficiencies.

With regard to (1) above, the usual sources of information are aerial photographs, soil maps, and anecdotal accounts because most wetland conversions were done before the era of formal delineation criteria and reports. Typically, areas shown on county soil survey maps to have hydric soils are presumed to be former wetlands, especially if historical airphotos also show flooding or characteristic wetland vegetation on the site. With regard to (2), it must be demonstrated that the current paucity of hydrophytic vegetation or other indicators (a, b, c) on the site is due to hydrologic changes, not to land-clearing associated with agriculture or other factors which, if alleviated, would likely result in hydrophytes recolonizing and hydric soil conditions returning. Caution is required in assessing these indicators because their current absence could be the result merely of changing local climate (drier years than formerly) or soil tillage, not reversible changes in site hydrology. Note also that for the purpose of mitigation banking, “restoration” does not include activities such as remediation of chemical contamination of a wetland, because such activities do not make a non-wetland become a wetland. Also, it does not include activities that reshape the plant community composition of a site (e.g., removal of exotics, burning) designed to shift dominance from non-hydrophytic to hydrophytic plant species, unless those activities can be demonstrated to sustainably restore the fundamental hydrology of the site. Some government agencies define restoration more broadly. For example, at a federal level the Interagency Workgroup on Wetland Restoration defined restoration as:

“the manipulation of the physical, chemical, or biological characteristics of a site with the goal of returning natural/historic functions to a former or degraded wetland.”

This definition also is being adopted by neighboring Clark County, Washington, where it is called wetland “re-establishment” rather than restoration. Note that this definition, in contrast to that used by DSL, does not limit restoration to activities accomplished through the manipulation only of site hydrology. Enhancement Potential The Oregon Department of State Lands (ORS 141-085) defines enhancement as:

“a human activity that increases the function of an existing degraded wetland.” In the context of wetland banking, to qualify for enhancement credit, the applicant must demonstrate that:

1) the site where compensatory activity is to be performed is currently a wetland, and 2) it is feasible to sustainably increase the capacity of the wetland to perform one or more functions, with minimal detriment to other functions.

Proposals for wetland enhancement also must “include a description of the factors leading to the degraded condition of the site.” This is important to assessing their reversibility. Depending on the situation, enhancement activities might include activities such as:

• prescribed burns in wetlands that historically were burned regularly • controlling invasive species and substituting native hydrophytes for them

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• revegetating upland buffer zones • recontouring a wetland or partially blocking/ unblocking surface water inputs or outputs

in order to change its hydroperiod (water persistence and depth). No formal, specific guidelines exist regarding which types of enhancement measures are acceptable to regulatory agencies for compensatory mitigation. In some states, measures such as bird nest boxes or platforms, fencing to exclude livestock, public access improvement, and predator removal have been awarded enhancement credits but these generally are not self-sustaining. For mitigation banking in the context of compensatory mitigation, DSL awards credits at the ratio of 1:1 for restoration, 2:1 for cropped wetlands, and 3:1 for other enhancement. Developer demand for credits obtained through enhancement is expected to be less because it involves purchase of credits from a greater acreage of wetland (2:1 or 3:1 compensation ratio) than required for purchase of credits obtained through wetland restoration (1:1 compensation ratio). Moreover, it is extremely difficult to demonstrate that proposed enhancements would not only replace fully the functions lost in the destroyed wetland, but also would go a step further and provide a level of function greater than existed in the destroyed wetland. Creation Potential Finally, wetlands are sometimes constructed (“created”) for use in compensatory mitigation. Wetland creation is defined as conversion of non-wetland, non-hydric (upland) areas to areas that eventually accrue the usual indicators of wetland environments (predominance of hydrophytes, reduced upper soil horizons, extended flooding). Preferably, the wetlands being created are of the same hydrogeomorphic subclass as the ones being destroyed. Wetlands are often more expensive to construct than to restore or enhance, and created wetlands tend more often to fail in acquiring a level of function equal to that of a wetland whose destruction they are intended to offset.

2. Methods At the request of MPG, a total of eight sites on Metro property were reviewed. Each site was believed to currently contain both wetland and non-wetland areas. To meet the requirements described above, five types of information were collected: Historical: Can it be demonstrated that any part of the non-wetland portion of the site was a wetland at some previous time? Current status as wetland: How much of the site is currently a wetland? Infrastructure: What water-controlling features of human origin are present? Feasibility: How likely is it that infrastructure alteration could successfully restore the site’s original hydroperiod? Over how much of the site could this be accomplished? Functions: What is the relative level of functions in the portion of the site that currently is a wetland? This provides a baseline against which possible future changes as a result of enhancements could be measured.

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To assess historical condition, aerial photographs and soils maps were examined. Current status as wetland was determined from on-site inspection using criteria of the 1987 Corps of Engineers Manual. However, a formal delineation of wetland boundaries was not requested at this time. Infrastructure was evaluated by review of consultant reports prepared prior to MPG acquisition of the sites, interviews with knowledgeable persons, airphotos (e.g., drain tile patterns), and on-site inspection. Specifically, the following types of hydrology-altering features – which could partly qualify a site as “restorable” -- were searched for:

• ditches • heavily incised channels • subsurface tile drains or well fields used to remove water from the soil more quickly

(evidenced by outlet pipes near streams, and/or drain tile patterns in aerial photographs) • artificial dams, berms, mounds, dikes, or levees used to divert water away from the site

Determining the presence of these comprehensively is a challenge, due to extensive overgrowth of the land surface with blackberries and other obscuring vegetation. Feasibility was assessed informally based on knowledge of similar restoration efforts and observation of topography and soils both on-site and in the local landscape. Functions were assessed by applying two rapid assessment methods supported by DSL: the reference-based Willamette Valley HGM Method (Adamus and Field 2001) and the Oregon Freshwater Wetland Assessment Method (OFWAM, Roth et al. 1996).

3. Site Descriptions Eight Metro properties that were examined are described below: Coffee Lake, Gales Creek, Madsen, Munger, Pigeon Lake, River Island, Weber Farms, and Wilsonville. Recent airphotos of each site, with property boundaries and National Wetland Inventory (NWI) overlay, were provided by MPG and reviewed. Only the portions of the properties delimited by MPG were inspected. The field inspections involved walking physically-accessible parts of the property perimeter and the boundaries of all areas on the property shown as wetlands by NWI. Site visits involved examining soil profiles, identifying dominant plants, assessing topography and water distribution, and noting infrastructure. The site descriptions that follow do not provide detailed data from these observations because no formal wetland delineations were required. For the same reason, the exact acreages of wetlands and restorable areas of each type were only estimated, not measured. Particular attention is given to 3 of the 8 sites which appeared to have the greatest potential.

3.1 Coffee Lake Site Visit: This 198-acre property was visited on November 3 and February 2. Rainfall totaled 1.34 inches in the week preceding the November visit, and 0.47 inches in the week preceding the February visit, during an unusually dry winter.

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Classification: According to the HGM classification, most of the property is a Slope wetland. The portion of the property that is associated with backing up of water in ditches is classified as Riverine Impounding, and comprises probably less than 20% of the assessment unit. According to the Cowardin classification, most of the assessment unit is classified Palustrine Emergent. Other Cowardin types present include:

Palustrine Scrub-Shrub Palustrine Forested Palustrine Aquatic Bed Palustrine Open Water Riverine

Land Cover: The property is almost entirely wetland, with only scattered uplands of coniferous and mixed woodland, and small amounts of blackberry and uncultivated field along the upland edge. None of the property is farmed currently, and portions of its southeastern and southwestern edges may have been grazed decades ago. The wetland’s watershed was historically dominated by agriculture and forest land, but industrial and commercial development is rapidly expanding along the eastern margin. Planning is currently underway for an extension of Boeckman Road which will cross the wetland near its south end. Topography and Hydrology: This large wetland drains westward into Coffee Creek (Seeley Ditch) which flows north to south. The property is generally flat and surrounded by gentle slopes on its east and west sides. Soils: Classified mainly as ponded humaquepts (hydric). Vegetation: The property is dominated by reed canary grass (Phalaris arundinacea), with lesser amounts of meadow grass (Alopecurus pratensis), rushes (Juncus effusus, J. patens, J. acuminatus, J. laccatus, J. ensifolius), sedge (Carex obnupta, C. feta, C. unilateralis), velvetgrass (Holcus lanatus), tufted hairgrass (Deschampsia caespitosa), bentgrass (Agrostis stolonifera), and other herbaceous species. Forested areas are primarily comprised of Douglas-fir and bigleaf maple, with some ash, western red cedar, and cottonwood. Brushy areas contain rose (Rosa nutkana), black hawthorn (Crataegus suksdorfii), willow (Salix spp.), alder (Alnus rubra), and meadowsweet (Spiraea douglasii). Function Assessment: The entire property was assessed as a Slope wetland. Scores for function capacity are shown in Table 1. Specific Comments on Habitat: Bird use was monitored regularly from the Grahams Ferry Road vantage point during winter 1994; data are available from the author. A road-killed mink (Mustella vison) was noticed along Grahams Ferry Road in September 2004. Portions of the property appear to be suitable for at least two sensitive species – red-legged frog and western pond turtle – although these were not searched for. Jurisdictional vs. NWI wetlands: Field examination determined that nearly all of the property meets jurisdictional criteria despite the fact that only a portion of the property is mapped by NWI

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as wetland. Most of the site was mapped as wetland by the Wilsonville Local Wetland Inventory and a formal wetland boundary delineation has been completed. Human Alteration of the Site: The wetland contains several unmaintained ditches that feed into Coffee Creek and were dug historically in unsuccessful attempts to drain parts of the wetland. Also, a small shallow pond (Coffee Lake) appears to have been excavated at unknown time in the eastern part of the wetland. Fill supporting Grahams Ferry Road bisects part of the wetland along its northwest side, and fill (side-cast spoil) also is present in limited areas along excavated ditches. An intermittent channel feeding the wetland from the east is visible in a 1963 topographic map but ground inspection showed it now barely exists. The site appeared generally similar in the 1939 aerial photograph. Opportunities: (1) Restoration: The fact that 42 of the property’s 198 acreas are on hydric soil but are not mapped as wetlands by NWI (areas labeled R on the accompanying map) suggests superficially a potential for 42 acres of restoration (Figure 1) However, during site inspection no evidence was found to suggest any substantial portion of this hydric soil has ceased to meet wetland jurisdictional criteria as a result of the historical alterations to hydrology. Moreover, the local wetland inventory shows nearly all the area being wetland. So, apparently NWI was too conservative in mapping of wetland extent at this location. Therefore, a potential of 42 restorable acres is an unlikely best-case estimate, and was somewhat arbitrarily revised downward to 5 acres pending future ground-level delineation and verification of wetland boundaries. (2) Enhancement: Some wetland functions might be enhanced in areas E1 and E2 by increasing water persistence on parts of this urban site, by controlling invasive vegetation, and by creating a vegetated woody buffer along parts of the perimeter. Water persistence might be accomplished by (a) partially blocking Seeley Creek and/or (b) plugging an intermittent tributary entering from the east side, and/or (c) removing sidecast fill along existing ditches. A conceptual plan by Ducks Unlimited further describes some options. Although a detailed hydrologic analysis would be necessary for accurate determination, the acreage of wetland potentially enhanced (or restored, if new flooding occurs on hydric non-wetland soils) by increasing water persistence is estimated at less than 0.5 acre. On the other hand, control of invasive vegetation might be accomplished on nearly all of the 101 acres that presently are mapped as wetland by NWI, plus the approximately 42 acres that currently appear to be wetland but were not mapped as such by NWI. (3) Creation: Wetland creation can be considered for the remaining 54 acres of the site that are neither hydric soil nor NWI-mapped wetland. However, the actual total that would allow creation of self-sustaining wetlands is negligable (estimated at less than 1 acre) because of the NWI mapping errors noted above (i.e., these areas are already wetland), and because of the sloping topography of the non-hydric soils.

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Table 1. Results of HGM function assessment for Coffee Lake wetland Calculated Function Capacity

for RI sites Function: if HFR: if LAR: Water Storage & Delay (ws) 0.20 0.20 Sediment Stabilization & Phosphorus Retention (sp) 0.73 0.73 Nitrogen Removal (n) 0.77 0.83 Thermoregulation (t) 0.06 0.06 Primary Production (pp) 0.59 0.59 Resident Fish Habitat Support (rf) 0.78 1.30 Anadromous Fish Habitat Support (af) 0.75 0.86 Invertebrate Habitat Support (i) 0.56 0.63 Amphibian & Turtle Habitat (at) 0.64 0.65 Breeding Waterbird Support (bw) 0.41 0.42 Wintering & Migrating Waterbird Support (ww) 0.57 0.77 Songbird Habitat Support (sb) 0.79 0.83 Support of Characteristic Vegetation (v) 0.74 0.84 * HFR = score relative to highest-functioning wetland of this HGM subclass that was assessed in the Willamette Valley. LAR= score relative to presumably least-altered wetland of this HGM subclass that was assessed in the Willamette Valley. The above scores do not directly account for the size of the wetland.

3.2 Gales Creek south Site Visit: The northern parcel of this 120-acre property was visited on November 19 and on February 2. Rainfall totaled 0.71 inches in the week preceding the November visit, and 0.47 inches in the week preceding the February visit, during an unusually dry winter. Classification: According to the HGM classification, most of the property is a Riverine Impounding wetland. Small portions that are not flooded directly by the creek but rather by precipitation and groundwater would be classified as Slope/Flats. According to the Cowardin classification, most of the assessment unit is classified Palustrine Emergent. Other Cowardin types present include:

Palustrine Scrub-Shrub Palustrine Open Water Riverine

Topography and Hydrology: During most winters when nearby Gales Creek is full, the north-south ditch that borders the wetland spills into the wetland and most of the property is inundated. Soils: Predominantly Aloha silt loam and silty clay loam (non-hydric), with some McBee silty clay loam (non-hydric), Woodburn silt loam (non-hydric), Cove silty clay loam (hydric), and Wapato silty clay loam (hydric).

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Land Cover: Over 70% of the site is currently cultivated. The remainder is wetland, shrubland, and small wooded areas. Vegetation: Portions of the property most likely to be jurisdictional wetland are dominated by reed canary grass, with lesser amounts of meadow grass (Alopecurus pratensis), rushes (Juncus effusus), sedge (Carex obnupta), bentgrass (Agrostis stolonifera), and other herbaceous species. Brushy areas contain rose (Rosa nutkana), black hawthorn (Crataegus suksdorfii), willow (Salix spp.), alder (Alnus rubra), and meadowsweet (Spiraea douglasii). Trees include Douglas-fir, ash, and cottonwood. Function Assessment: Functions were assessed only in the portions of the property considered most likely to be jurisdictional wetland. These correspond generally with wetland boundaries shown on the NWI map. Scores are shown in Table 2. Specific Comments on Habitat: Several Wilson’s Snipe were flushed from the wettest portion of the site. This shorebird species is believed to be declining in the Willamette Valley. Jurisdictional vs. NWI wetlands: Field indicators suggested little if any of the area outside of the NWI-mapped wetland meets jurisdictional criteria, due general lack of soil redoximorphic indicators and limited prevalence of hydrophytic vegetation. Human Alteration of the Property: The deeply incised ditch is the only infrastructural feature on the site. Where a farm road crosses it, the culvert has partially collapsed and flow is somewhat slowed. The site appeared generally similar in the 1939 aerial photograph. Opportunities: (1) Restoration: The GIS overlay of soils and wetlands indicates a potential for 77.1 acres of restoration (Figure 2). A ditch bisects much of the mapped wetland and extends across areas of hydric soil (former wetlands) that currently are cultivated and showed little or no evidence of hydric indicators. The original reconnaissance report to Metro regarding purchase of this property noted that most of it floods annually or semiannually when Gales Creek is too full to allow unhindered discharge of this drainage ditch. The lack of hydric soil indicators suggests flooding is brief, or soil indicators have been erased by repeated plowing. Restoration would involve (1) partially blocking the ditch with a water control structure where it is crossed by the farm road (marked R on the accompanying map), and possibly farther downstream, (2) regrading portions of the property that are on mapped hydric soil near the ditch, to allow floodwater to expand after cultivation of these lands ceases, and (3) intercepting overland runoff in the more southerly of the 2 units (marked R2). (2) Enhancement: The existing 11-acre wetland is in generally good condition and thus could provide only modest enhancement credits, these being from control of reed canarygrass (marked W on the accompanying map). (3) Creation: Limited opportunities might be present on parts of the site that are not hydric soil.

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Table 2. Results of HGM function assessment for Gales Creek south wetland Calculated Function Capacity

for RI sites Function: if HFR: if LAR: Water Storage & Delay (ws) 0.20 0.20 Sediment Stabilization & Phosphorus Retention (sp) 0.84 0.84 Nitrogen Removal (n) 0.71 0.76 Thermoregulation (t) 0.06 0.06 Primary Production (pp) 0.66 0.66 Resident Fish Habitat Support (rf) 0.74 1.24 Anadromous Fish Habitat Support (af) 0.72 0.83 Invertebrate Habitat Support (i) 0.59 0.65 Amphibian & Turtle Habitat (at) 0.53 0.54 Breeding Waterbird Support (bw) 0.00 0.00 Wintering & Migrating Waterbird Support (ww) 0.80 1.08 Songbird Habitat Support (sb) 0.91 0.96 Support of Characteristic Vegetation (v) 0.75 0.86 * HFR = score relative to highest-functioning wetland of this HGM subclass that was assessed in the Willamette Valley. LAR= score relative to presumably least-altered wetland of this HGM subclass that was assessed in the Willamette Valley. The above scores do not directly account for the size of the wetland.

3.3 Madsen Site Visit: This 15-acre property was visited on November 10 and on February 2. Rainfall totaled 0.80 inches in the week preceding the November visit, and 0.47 inches in the week preceding the February visit, during an unusually dry winter. Classification: Two assessment units were delimited. One, an excavated pond near the residence, is classified as Depressional according to the HGM classification because much of its water appears to be runoff from adjoining fields and forest. By the Cowardin classification, this pond is Palustrine Open Water. The other assessment unit, a slough downhill from the pond, is mainly a Slope wetland, although perhaps a century or more ago when the Tualatin River was less incised, this wetland may have been a permanently-connected side channel or oxbow. If a portion still floods biennially by overflow from the Tualatin River, it would be classified as Riverine Impounding. According to the Cowardin classification, most of this unit is classified Palustrine Emergent. Other Cowardin types present include:

Palustrine Scrub-Shrub Palustrine Forested Palustrine Aquatic Bed Palustrine Open Water

Land Cover: The property borders the Tualatin River and is predominantly cropland, followed by wetland, mixed woodland, and residential yard. The site appeared generally similar in the 1939 aerial photograph, but the pond was not apparent.

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Topography and Hydrology: During some winters the Tualatin River may spill into a small portion of the lower part of the property – this is uncertain. The excavated pond in the upper part of the property may occasionally outflow into the lower wetland, which lacks a year-round connection to the Tualatin River. Soils: Most of the site is Chehalis silty clay loam and Hillsboro loam. Both are non-hydric. The wetter areas contain Wapato silty clay loam and Cove clay, both of which are hydric. Vegetation: Portions of the property most likely to be jurisdictional wetland are dominated by reed canary grass. Himalayan blackberry dominates along much of the upslope side of the lower wetland. Function Assessment: Functions were assessed only in the portions of the property considered most likely to be jurisdictional wetland, and/or within the 2-year floodplain. The upper pond was assessed as one unit, and the lower wetland was assessed as another unit. Scores are shown in Table 3. Specific Comments on Habitat: A peregrine falcon was noted at the western end of the property during the November visit. The lower wetland appears suitable for red-legged frog and possibly western and painted turtles, although these were not searched for. Jurisdictional vs. NWI wetlands: The NWI map of the property is generally accurate in its depiction of wetlands. Soils that adjoin the NWI-mapped wetlands are classified as hydric by the county soil survey, but due to cultivation they mainly lack a predominance of hydrophytic vegetation and indicators of redoximorphic indicators conditions. Human Alteration of the Site: The upper pond almost certainly was excavated and has a berm that blocks outflow. Some water is removed from it in summer for irrigation use. The lower pond has no control structures. Its relative isolation from the Tualatin River is the result of progressive downcutting of the river, with resultant lowering of the wetland’s water table and duration of seasonal flood connection. Decades of cultivation have removed forest cover in most of the property. Some minor recontouring of fields has occurred as a result of farming activities. Opportunities: (1) Restoration: Portions of the site that are mapped as hydric soil (Cove or Wapato series) coincide with the wetland boundary as shown on NWI maps (Figure 3). An exception is a small area at the east end of the wetland (labeled R on the accompanying map), which potentially could be considered for restoration. However, site inspection revealed wetland indicators and no evidence of infrastructure that could depress water tables or exclude flooding, so it is more likely a candidate for enhancement than restoration. (2) Enhancement: Some wetland functions might be enhanced by controlling invasive plants in the wetland (E1), and establishing a buffer of native vegetation along part of the southern edge of the wetland where adjoining land is now farmed (E2). (3) Creation: Opportunities for successful creation of wetlands from uplands are most feasible through excavation, and at location “R” or other low spots shown on the accompanying map.

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Table 3. Results of HGM function assessment for Madsen wetland Calculated Function

Capacity for SF sites Function: if HFR: if LAR: Water Storage & Delay (ws) 0.50 1.11 Sediment Stabilization & Phosphorus Retention (sp) 0.89 0.96 Nitrogen Removal (n) 1.03 1.03 Primary Production (pp) 0.82 0.86 Invertebrate Habitat Support (i) 0.73 0.73 Amphibian & Turtle Habitat (at) 0.90 1.19 Breeding Waterbird Support (bw) 1.01 1.17 Wintering & Migrating Waterbird Support (ww) 0.60 0.69 Songbird Habitat Support (sb) 0.88 1.34 Support of Characteristic Vegetation (v) 0.65 0.68 * HFR = score relative to highest-functioning wetland of this HGM subclass that was assessed in the Willamette Valley. LAR= score relative to presumably least-altered wetland of this HGM subclass that was assessed in the Willamette Valley. The above scores do not directly account for the size of the wetland.

3.4 Munger Site Visit: This 83-acre property was visited on November 10 and on February 2. Rainfall totaled 0.80 inches in the week preceding the November visit, and and 0.47 inches in the week preceding the February visit, during an unusually dry winter. Classification: One assessment unit was delimited. It is classified as a Slope wetland according to the HGM classification because much of its water appears to originate from groundwater seepage from the adjoining slope and uphill fields. However, the lower fields in this site are reportedly flooded most years, making a portion of the site a Riverine Impounding wetland. The geomorphology of this unit suggests that at least a century ago its some of its lower portion may have been an oxbow or side channel that was connected at least seasonally with the Tualatin River. By the Cowardin classification, most of this unit is classified as Palustrine Emergent, but there also are significant areas of Palustrine Scrub-Shrub and Palustrine Forested wetland, and a small amount of Palustrine Open Water. Land Cover: The property borders the Tualatin River and is predominantly cropland, followed by mixed woodland, wetland, and residential yard. Topography and Hydrology: The wetland appears to be inundated mainly as a result of seepage, surface runoff, and direct precipitation, but during some years overbank flooding from the Tualatin River is a major influence. Soils: The county soil maps show the most extensive soils to be McBee silty clay loam, Chehalis silty clay loam, and Quatama loam. None of these are hydric. Also present, mainly in the relict oxbows, is Cove clay which is classified as hydric..

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Vegetation: Portions of the property most likely to be jurisdictional wetland are dominated by reed canary grass Himalayan blackberry dominates along much of the upslope side of the lower wetland. On the hillslope, a profusion of seeps is characterized by slough sedge. Function Assessment: Functions were assessed in the area mapped by NWI as wetland, i.e., the relict oxbow in the lower part of the site, extending onto the slopes where slough sedge (Carex obnupta) prevail beneath a forest canopy. Scores are shown in Table 4. Specific Comments on Habitat: Ponded areas within the shrub wetland appear suitable for red-legged frog, although these were not searched for. Jurisdictional vs. NWI wetlands: The NWI map of the property is generally accurate in its depiction of wetlands. Soils within the NWI-mapped wetlands are classified as hydric, but the adjoining cultivated floodplain soils are not. Human Alteration of the Site: The wetland’s relative isolation from the Tualatin River is the result of progressive downcutting of the river, with resultant lowering of the wetland’s water table and duration of seasonal flood connection. Decades of cultivation have removed forest cover in about half of the property. It is likely some of the cropped area has been extensively recontoured by farming activities. No tile drains, ditches, or other direct alterations to the hydrology of the site were detected. Opportunities: (1) Restoration: The only part of the property that is mapped as hydric soil but not as wetland is along a line (R, on the accompanying map, Figure 4) between the river channel and the oxbow wetland that now is isolated from the river. Conceivably a connection could be excavated between the oxbow and the river, and wetland vegetation allowed to develop within the excavated path. However, the river’s current elevation may be too low (relative to the wetland) to allow for even an annual seasonal connection; this should be confirmed with an engineering survey. In addition, impacts on any amphibians inhabiting the existing wetland, and the potential for fish stranding, should be considered if seasonal reconnection of the oxbow is pursued. (2) Enhancement: If aggressive control of invasive vegetation were maintained in the area marked E1, this might qualify for enhancement credit. A partially wooded buffer also might be established in the area marked E2. (3) Creation: Despite the soil being classified as non-hydric, small pockets of hydric soil were found in the lower cultivated area and would be the most likely focal points for a minor amount (< 1 acre) of wetland restoration or creation, such as by deepening low spots in the cultivated field.. Table 4. Results of HGM function assessment for Munger wetland Calculated Function

Capacity for SF sites Function: if HFR: if LAR: Water Storage & Delay (ws) 0.05 0.11 Sediment Stabilization & Phosphorus Retention (sp) 0.77 0.82 Nitrogen Removal (n) 0.96 0.96

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Calculated Function Capacity for SF sites

Primary Production (pp) 0.82 0.82 Invertebrate Habitat Support (i) 0.47 0.47 Amphibian & Turtle Habitat (at) 0.96 1.27 Breeding Waterbird Support (bw) 0.00 0.00 Wintering & Migrating Waterbird Support (ww) 0.42 0.49 Songbird Habitat Support (sb) 0.85 1.30 Support of Characteristic Vegetation (v) 0.68 0.70 * HFR = score relative to highest-functioning wetland of this HGM subclass that was assessed in the Willamette Valley. LAR= score relative to presumably least-altered wetland of this HGM subclass that was assessed in the Willamette Valley. The above scores do not directly account for the size of the wetland.

3.5 Pigeon Lake Site Visit: This property was visited on October 15 and on February 2. Rainfall totaled 0.79 inches in the week preceding the October visit, and 0.47 inches in the week preceding the February visit, during an unusually dry winter. Classification: By the HGM classification for Oregon, the property has two distinct wetland units. One, the deep pond adjoining the east side of the entrance road -- may be classified as a Depressional Outlet wetland or a Slope wetland. The other, which comprises most of the remaining wetland area on the property, may be classified as Riverine Impounding. According to the Cowardin classification, the pond may be classified as Palustrine Unconsolidated Bottom, while the remainder of the wetland on the property would be classified mainly as Palustrine Forested and Palustrine Scrub-Shrub. Land Cover: The eastern half of the property is farmed (cabbage in summer 2004). Most of the rest of the property is coniferous and mixed woodland, with a smaller amount of emergent and shrub wetland. Topography and Hydrology: An aerial photograph from 1936 shows a large cutoff meander looping through the site, and remnants remain. During most winters the Clackamas River spills into a portion of the property and may cause temporary backing up of Richardson Creek. Richardson Creek, which supports spawning coho, originates on slopes to the northeast and follows the northern and western boundary of the property before flowing into the Clackamas River. A deep pond adjoins the east side of the entrance road from Route 224. The pond has no permanent inlet but may receive occasional input from Richardson Creek. A water control structure is present at the outlet but may not be functional, as a small amount of water was seen flowing around it. Outflow supplies a deep, narrow ditch which becomes an intermittent tributary of Richardson Creek further west and contains a small, old beaver dam. Another noteworthy feature is a wooded wetland south of the ditch. This wetland remains inundated year-round and has a shallow connection to the ditch that eventually connects to Richardson Creek and the Clackamas River.

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Soils: The site contains Cloquato silt loam, McBee silty clay loam, and Newberg loam. None of these are classified as hydric, so it is unlikely that jurisdictional wetlands existed historically on any extensive part of the site, although the site very clearly is and was part of the annual floodplain of the Clackamas River. Vegetation: Portions of the property most likely to be jurisdictional wetland are dominated by invasive plants, primarily reed canary grass, yellow water-flag (Iris pseudacorus), and Japanese knotweed (Polygonum cuspidatum). Native wetland and riparian plants mainly include red alder, hazel, elderberry, bigleaf maple, cascara, cedar, grand fir, and black cottonwood . Much of the surface of the deep pond is dominated by pond lily (Nuphar lutea), while its shorelines are carpeted with reed canary grass and soft rush. Function Assessment: Functions were assessed only in the portions of the property considered most likely to be jurisdictional wetland, and/or within the 2-year floodplain. The deep pond was assessed as one unit, and the forested wetland (including the ditch and lower Richardson Creek) was assessed as another unit. Scores for the latter are shown in Table 5. Specific Comments on Habitat: Pileated woodpecker (a state-listed sensitive species) was detected during the October visit. The wooded wetland appears suitable for another sensitive species – red-legged frog – although these were not searched for. Non-native bullfrogs are abundant in the deep pond. Jurisdictional vs. NWI wetlands: Passage of the Clackamas River along the property is mapped by NWI as a riverine wetland, but field indicators suggested little if any of the mapped wetland meets jurisdictional criteria, due general lack of soil redoximorphic indicators and limited prevalence of hydrophytic vegetation. Human Alteration of the Site: The deep pond almost certainly was excavated. A short cobble berm is present behind structures on the property, separating them from Richardson Creek, and is probably of human origin. It is likely some of the cropped area has been recontoured by farming activities. Opportunities: (1) Restoration: About 1.5 acres of restoration may be possible, based on overlay of hydric soils map with NWI wetlands map. The most feasible option is probably to remove the low berm that separates a few buildings from Richardson Creek (marked R on the accompanying map, Figure 5). Because this could seasonally flood the buildings, they would need to first be removed. In addition, it is likely that area along the path of the old cutoff meander that currently are not wetlands (marked C on the accompanying map), may have historically been wetlands, although maps do not show hydric soil there. Restoration of the historic wetlands could be accomplished by regrading part of the cultivated field so that existing wetlands connect to the Clackamas River. However, efforts to reinstate the full meander loop are unlikely to succeed because the mainstem is now regulated by dams, and has substantially changed course and incised its channel, which is bounded by coarse-textured alluvial soils.

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(2) Enhancement: Aggressive and sustained control of invasive vegetation along the shore of the pond and in the existing wetland comprising the backwater of the Clackamas River (marked E on the map) might yield some enhancement credits. (3) Creation: Opportunities for creation would be limited, at best, to the 53 acres of the property that are neither wetland nor hydric soil. (If regrading the old meander loop is considered creation rather than restoration, it would add to this total). Table 5. Results of HGM function assessment for Pigeon Lake wetland Calculated Function Capacity

for RI sites Function: if HFR: if LAR: Water Storage & Delay (ws) 0.14 0.14 Sediment Stabilization & Phosphorus Retention (sp) 0.69 0.69 Nitrogen Removal (n) 0.78 0.84 Thermoregulation (t) 0.29 0.29 Primary Production (pp) 0.79 0.79 Resident Fish Habitat Support (rf) 0.99 1.65 Anadromous Fish Habitat Support (af) 0.82 0.95 Invertebrate Habitat Support (i) 0.86 0.96 Amphibian & Turtle Habitat (at) 0.82 0.83 Breeding Waterbird Support (bw) 0.00 0.00 Wintering & Migrating Waterbird Support (ww) 0.46 0.62 Songbird Habitat Support (sb) 0.83 0.88 Support of Characteristic Vegetation (v) 0.61 0.69 * HFR = score relative to highest-functioning wetland of this HGM subclass that was assessed in the Willamette Valley. LAR= score relative to presumably least-altered wetland of this HGM subclass that was assessed in the Willamette Valley. The above scores do not directly account for the size of the wetland

3.6 Weber Farms Site Visit: This 16-acre property was visited on October 16 and February 2. Rainfall totaled 0.79 inches in the week preceding the October visit. It was not visited again. Classification: By the HGM classification for Oregon, the main wetland on the property is classified as Riverine Flow-through. It is partly the result of partial blockage of a stream (by beaver) as the stream flows south and east into the Willamette River, but it also receives substantial groundwater and runoff from the adjoining slopes. By the Cowardin classification, it includes the following classes: Palustrine Emergent

Palustrine Scrub-Shrub Palustrine Forested Palustrine Unconsolidated Bottom Riverine

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Another assessment unit is on a plateau in the northwestern part of the site, and it was unclear whether indicators are sufficient to qualify it as jurisdictional wetland. If it is, it would be classified as a Slope (HGM) and Palustrine Emergent (Cowardin) wetland. Topography and Hydrology: One wetland (termed the “lower wetland”) lies between the cultivated fields near the Willamette River and a steep wooded slope that rises to the plateau comprising the rest of the property. This wetland appears to be a primary source of water for a creek that flows eastward through the forest. It is assumed, but was not confirmed, that there are no impassible fish barriers between this creek, the Willamette River, and this wetland. A separate wetland (actually, a complex of many very small wetlands) is termed the “upper wetland” and is located in open (mostly logged-over) areas on the plateau at the northwest portion of the property. It contains scattered pools of water only during winter and is not on hydric soil. A stream just west of the upper fields is bounded by steep slopes and flows southward toward the lower wetland. Soils: The site contains Cloquato silt loam, McBee silty clay loam, and Newberg loam. None of these are classified as hydric, so it is unlikely that jurisdictional wetlands existed historically on any extensive part of the site. Land Cover: The lower wetland is bounded on the south by cropland and on other sides by forest. The upper wetland complex is surrounded by natural vegetation typical of post-clearcut environments. Vegetation: Portions of the property most likely to be jurisdictional wetland are dominated by invasive plants, primarily reed canary grass (lower wetland) and soft rush (Juncus effusus, upper wetland complex). Jurisdictional vs. NWI wetlands: The only wetland shown on current NWI maps of this property no longer exists, and in fact may never have existed. No hydric soils or hydrophytic vegetation were found at that location. Function Assessment: Functions were assessed only in the lower wetland. Scores are shown in Table 6. Specific Comments on Habitat: Pileated woodpecker (a state-listed sensitive species) was detected during the October visit. The wetland appears suitable for another sensitive species – red-legged frog – although these were not searched for. Human Alteration of the Site: No obvious alterations to the natural hydrology of the site were noticed. It is likely some of the cropped area has been recontoured by farming activities. Opportunities: (1) Restoration: Because none of the site’s soils are mapped as hydric soil, restoration opportunities are unlikely to exist. (2) Enhancement: Some functions in the existing wetland (marked E1, Figure 6) that exists on non-hydric soil might be enhanced by aggressively maintaining control of invasive vegetation.

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Also, a partially wooded buffer could be established where cropland now exists along the southern edge of this wetland. (3) Creation: Small seasonal pools might be excavated in the logged area (C1). Runoff in the swale marked C2 might be detained with a checkdam to create a small seasonal wetland. Shallow pools might also be excavated in existing low spots in the field such as near C3. Table 6. Results of HGM function assessment for Weber Farms wetland Calculated Function Capacity

for RI sites Function: if HFR: if LAR: Water Storage & Delay (ws) 0.06 0.06 Sediment Stabilization & Phosphorus Retention (sp) 0.79 0.79 Nitrogen Removal (n) 0.75 0.81 Thermoregulation (t) 0.11 0.11 Primary Production (pp) 0.82 0.82 Resident Fish Habitat Support (rf) 1.04 1.74 Anadromous Fish Habitat Support (af) 0.62 0.72 Invertebrate Habitat Support (i) 0.64 0.72 Amphibian & Turtle Habitat (at) 0.82 0.84 Breeding Waterbird Support (bw) 0.00 0.00 Wintering & Migrating Waterbird Support (ww) 0.43 0.58 Songbird Habitat Support (sb) 0.88 0.93 Support of Characteristic Vegetation (v) 0.58 0.65 * HFR = score relative to highest-functioning wetland of this HGM subclass that was assessed in the Willamette Valley. LAR= score relative to presumably least-altered wetland of this HGM subclass that was assessed in the Willamette Valley. The above scores do not directly account for the size of the wetland

3.7 Wilsonville Site Visit: This 262-acre property was visited on November 19. Rainfall totaled 0.71 inches in the week preceding the November visit, and and 0.47 inches in the week preceding the February visit, during an unusually dry winter. Only the parcel north of Wilsonville Road was visited. Classification: By the HGM classification for Oregon, the sole wetland on the property would be classified as Slope/Flat. By the Cowardin classification, this wetland may include the following classes: Palustrine Emergent, Palustrine Scrub-Shrub. Topography and Hydrology: The site generally slopes westward toward Mill Creek, and has distinctly rolling topography (slopes mostly 3-15%).. Soils: Mostly Aloha silt loam (non-hydric), with inclusions of Woodburn silt loam (non-hydric), Amity silt loam (non-hydric), and Dayton silt loam (hydric).

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Land Cover: Most of the property is farmed, with bare fields predominating during the November 2004 visit. A small filbert orchard is present in the southwestern corner. The western boundary is extensively forested (coniferous and mixed woodland). Vegetation: Portions of the property most likely to be jurisdictional wetland are in a fenced area adjoining the school on the east side, where mapped as Dayton silt loam. That area is dominated by invasive reed canary grass. Scattered amid the field are a few tiny (<0.1 acre) artificial depressions that are not plowed and contain reed canary grass. Function Assessment: Functions were assessed only in the fenced wetland, and results are shown in Table 7. Specific Comments on Habitat: Portions of the field in its current condition provide excellent habitat for wintering shorebirds, notably killdeer. Jurisdictional vs. NWI wetlands: Only the portion of the property on Dayton silt loam is mapped by NWI as a wetland. Field indicators suggested little if any of the cultivated portion on Woodburn, Amity, or Aloha soils would meet wetland jurisdictional criteria, due general lack of soil redoximorphic indicators and absence of hydrophytic vegetation. Human Alteration of the Property: A single tile drain outlet was noted along the western margin of the field. Its effluent flows eastward to Mill Creek in an intermittent incised channel through the forest. A pipe that conducts stormwater away from developments to the east underlies non-wetland parts of the site. Opportunities: (1) Restoration: There is an area (R on the accompanying map, Figure 7) mapped as hydric soil that is no mapped as wetland by NWI, and which site inspection showed to be mostly lacking in wetland indicators. Some of this area is underlaid by tile drains, and might be a candidate for restoration. Blockage of the tile drains, accompanied by some regrading, might effectively extend an existing wetland (W) in a westerly direction. However, the current value of that area as shorebird habitat (vegetation sparse or lacking due to cultivation) could exceed its value for other functions that might be restored. (2) Enhancement: A buffer might be created along part of the existing wetland’s (W) west side, and within the wetland aggressive control of invasive vegetation might be maintained, thus possibly qualifying for enhancement credit. (3) Creation: No opportunities for creation were identified. Creation is severely limited by the sloping topography of the site. Table 7. Results of HGM function assessment for Wilsonville wetland Calculated Function

Capacity for SF sites Function: if HFR: if LAR: Water Storage & Delay (ws) 0.50 1.11 Sediment Stabilization & Phosphorus Retention (sp) 0.86 0.92 Nitrogen Removal (n) 0.94 0.94

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Calculated Function Capacity for SF sites

Primary Production (pp) 0.70 0.82 Invertebrate Habitat Support (i) 0.37 0.37 Amphibian & Turtle Habitat (at) 0.64 0.84 Breeding Waterbird Support (bw) 0.00 0.00 Wintering & Migrating Waterbird Support (ww) 0.53 0.61 Songbird Habitat Support (sb) 0.42 0.65 Support of Characteristic Vegetation (v) 0.61 0.64 * HFR = score relative to highest-functioning wetland of this HGM subclass that was assessed in the Willamette Valley. LAR= score relative to presumably least-altered wetland of this HGM subclass that was assessed in the Willamette Valley. The above scores do not directly account for the size of the wetland

3.8 River Island Site Visit: This 50-acre property along the Clackamas River was visited briefly in September, but not assessed further. Classification: Only the MPG unit on the south side of the Clackamas River was visited. This unit contains a Riverine Impounding wetland (as classified by the HGM classification) which under the Cowardin classification is a Riverine Unconsolidated Bottom wetland with a Palustrine Scrub-shrub fringe. Topography and Hydrology: Not assessed. Soils: The site contains Cloquato silt loam, McBee silty clay loam, and Newberg loam. None of these are classified as hydric, so it is unlikely that jurisdictional wetlands existed historically on any extensive part of the site. Land Cover: The property is mostly an abandoned gravel operation. The property contains extensive coniferous and mixed woodland, with a smaller amount of emergent and shrub wetland. Vegetation: Portions of the property most likely to be jurisdictional wetland are dominated by reed canary grass. Native wetland and riparian plants mainly include willow and black cottonwood. Function Assessment: Functions were not assessed. Specific Comments on Habitat: Pileated woodpecker (a state-listed sensitive species) was detected during a September visit. Jurisdictional vs. NWI wetlands: Passage of the Clackamas River along the property is mapped by NWI as a riverine wetland, but field indicators suggested little if any of the mapped wetland meets jurisdictional criteria, due general lack of soil redoximorphic indicators and limited prevalence of hydrophytic vegetation.

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Human Alteration of the Property: Previous gravel operations have altered the topography of the site. Restoration Opportunities: Not assessed.

4. Conclusions

Opportunities for wetland restoration on these properties appear to be very limited, and opportunities for wetland enhancement and creation are moderately limited. The tables below summarize this assessment of wetlands on selected MPG properties. Table 8. Potential opportunities (acres) for wetland restoration measures at MPG properties Potential

Total Tile Drain Plugging

Ditch Plugging

Berm Removal

Regrading

Coffee Lake < 5 ♦ ♦Gales Creek south < 77 ♦ ♦Madsen 0 Munger < 20 Pigeon Lake < 8 ♦ ♦Weber Farms 0 Wilsonville < 18 ♦ ♦ NOTE: The estimated acreages are based on cursory visual field inspection, not on an engineering analysis or formal field delineation of each site’s restorable area. No inference should be made regarding the technical feasibility, safety, legality, or economics of implementing these measures, or the likelihood that regulatory agencies will find any or all of these measures acceptable for compensatory mitigation. Table 9. Potential opportunities (acres) for wetland enhancement measures at MPG properties

Potential Total

Invasive Species Control

Increase Water Persistence*

Buffer Revegetation*

Coffee Lake ~90 ♦ ♦ ♦ Gales Creek south ~11 ♦ ♦ ♦ Madsen ~ 3 ♦ ♦ ♦ Munger ~ 2 ♦ ♦ Pigeon Lake ~ 12 ♦ ♦ Weber Farms ~ 2 ♦ ♦ Wilsonville ~10 ♦ ♦ ♦

* Increase Water Persistence = accomplished via topographic grading, placement of berms or dams, and/or addition of water control structures. Buffer Revegetation = passive or active establishment of native vegetation in agricultural lands within 100 ft upslope of the wetland boundary. Of the wetlands examined, the priority for enhancement (based on currently low capacity of functions as shown in Table 11) would be approximately: Munger> Pigeon Lake> Weber Farms> Wilsonville> Gales Creek> Coffee Lake> Madsen. No inference should be made regarding the technical feasibility, safety, legality, or economics of implementing these measures, or the likelihood that regulatory agencies will find any or all of these measures acceptable for compensatory mitigation.

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Table 10. Potential opportunities (acres) for wetland creation at MPG properties

Potential Total

Drainage Blocking

Excavation

Coffee Lake < 1 ♦ ♦ Gales Creek south <10 ♦ ♦ Madsen <10 ♦ ♦ Munger <10 ♦ ♦ Pigeon Lake < 10 ♦ ♦ Weber Farms < 5 ♦ ♦ Wilsonville < 10 ♦ ♦

NOTE: The above figures merely represent acreage that is neither hydric soil nor wetland, and is not steeply sloping. The actual potential for creating sustainable wetlands is considerably less than shown, due to the steep slopes of uplands on most of these sites. Drainage Blocking = increased water extent on non-hydric non-wetland soils, accomplished via placement of berms or dams and/or addition of water control structures. Excavation = regrading to create sustainably wet depressions in flat uplands with non-hydric soil. No inference should be made regarding the technical feasibility, safety, legality, or economics of implementing these measures, or the likelihood that regulatory agencies will find any or all of these measures acceptable for compensatory mitigation.

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Table 11. Estimates of the relative levels of functions in the existing wetlands The numbers are relative to the highest-functioning (score = 1.0) reference wetlands assessed previously by the Willamette Valley HGM Method. The scores do not directly account for the size of the wetland.

Coffee Lake

Gales C

reek

Madsen

Munger

Pigeon Lake

Weber Farm

s

Wilsonville

Water Storage & Delay 0.20 0.20 0.50 0.05 0.14 0.06 0.50 Sediment Stabilization & Phosphorus Retention 0.73 0.84 0.89 0.77 0.69 0.79 0.86 Nitrogen Removal 0.77 0.71 1.03 0.96 0.78 0.75 0.94 Thermoregulation 0.06 0.06 0.82 0.82 0.29 0.11 0.70 Primary Production 0.59 0.66 0.73 0.47 0.79 0.82 0.37 Resident Fish Habitat Support 0.78 0.74 0.90 0.96 0.99 1.04 0.64 Anadromous Fish Habitat Support 0.75 0.72 1.01 0.00 0.82 0.62 0.00 Invertebrate Habitat Support 0.56 0.59 0.60 0.42 0.86 0.64 0.53 Amphibian & Turtle Habitat 0.64 0.53 0.88 0.85 0.82 0.82 0.42 Breeding Waterbird Support 0.41 0.00 0.65 0.68 0.00 0.00 0.61 Wintering & Migrating Waterbird Support 0.57 0.80 0.50 0.05 0.46 0.43 0.50 Songbird Habitat Support 0.79 0.91 0.89 0.77 0.83 0.88 0.86 Support of Characteristic Vegetation 0.74 0.75 1.03 0.96 0.61 0.58 0.94

5. Literature Cited Adamus, P.R. and D. Field. 2001. Guidebook for Hydrogeomorphic (HGM)–based Assessment of Oregon Wetland and Riparian Sites. I. Willamette Valley Ecoregion, Riverine Impounding and Slope/Flat Subclasses. Volume IA: Assessment Methods. Oregon Division of State Lands, Salem, OR. Roth, E., R. Olsen, P. Snow, and R. Sumner. 1996. Oregon Freshwater Wetland Assessment Method. Wetlands Program, Oregon Div. State Lands, Salem, OR.

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Figure 1. Coffee Lake property showing general vicinity of potential restoration (R1, R2, R3) and enhancement (E1, E2) opportunities

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Figure 2. Gales Creek south property showing general vicinity of potential restoration (R, R2) or enhancement (W)

Figure 3. Madsen property showing general vicinity of potential restoration (R), enhancement (E1, E2), or creation (C) opportunities

Figure 4. Munger property showing general vicinity of potential restoration (R), enhancement (E1, E2), or creation (C) opportunities

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Figure 5. Pigeon Lake property showing general vicinity of potential restoration (R), enhancement (E), or creation (C) opportunities

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Figure 6. Weber Farms property showing general vicinity of potential enhancement (E1,

E2) or creation (C1, C2, C3) opportunities

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Figure 7. Wilsonville property showing general vicinity of potential restoration (R) or enhancement (W) opportunities

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