CITY OF GRESHAM Urban Design & Planning 1333 NW Eastman Parkway Gresham, OR 97030 STAFF REPORT TYPE II FINDINGS AND RECOMMENDATIONS DATE:
August 15, 2017
FROM:
Ricardo Banuelos, Assistant Development Planner
FILE NUMBER:
SD/TR/MIS 17-26000019
APPLICANT:
M&T Development, LLC
LOCATION:
1300 SW 21st Ter., Gresham OR 97080
PARCEL DESCRIPTION:
1S3E16CA 10400
PROPOSAL:
A 14-lot subdivision of approximately 6,200 square-foot average sized single-family detached residential lots. Removal of 14 regulated trees, a Hillside street extension, and dedication of 0.45 acres of Habitat Conservation Area. The pre-existing dwelling is proposed to be resituated onto proposed Lot 5. No habitat conservation area disturbance is proposed for construction of public facilities or vegetation clearing and grading associated with proposed building pads.
DECISION:
APPROVAL with Conditions
EXHIBITS:
A. Vicinity Map B. Applicant’s Narrative Materials and Plans C. Public Comments D. Email from GeoTechnical Engineer E. Third Party GeoTechnical Review F. Lot Reconfiguration Alternatives & Staff Preferred Alternatives
The following are the Findings and Approval with Conditions for SD/TR/MIS 17-26000019 for a 14-lot subdivision, removal of 14 trees, and no Habitat Conservation Area disturbance. The proposal was reviewed in accordance with the standards of the Gresham Community Development Code (GCDC) Sections: •
4.0100 - Residential Land Use Districts
•
5.0200 - Hillside Physical Constraint Overlay
•
5.0400 - Habitat Conservation Area
•
6.0000 - Land Divisions
•
9.0200 - Clear Vision Area
•
9.0500 - Grading Drainage and Stormwater Quality Control
•
9.0700 - Neighborhood Circulation and Future Street Plans
•
9.0800 - Parking
•
9.1030 - Tree Regulations for Single-Family Detached Dwellings
•
11.0400 - Type II Development Permit Applications.
I. FINDINGS Findings of Fact The proposed 14-lot subdivision is located at 1300 SW 21st Ter. It is a 121,853 square-foot lot (2.8 acres) that is zoned Low Density Residential - 7 (LDR-7). The lot is located south of Gresham Butte and contains one existing single-family residential home. The surrounding neighborhood to the north, south, and west consist of single-family residential homes in the LDR-5 and LDR-7 zones. To the east is a vacant wooded open space area that is owned and managed by the City of Gresham. There are two environmental overlay districts affecting the site (Figure 1); the Habitat Conservation Area (HCA) and Hillside Physical Constraint (Hillside) overlays. There are numerous regulated size trees and a forest understory that is concentrated to a ravine along the eastern edge of the lot. Chastain Creek runs south/north just beyond the east property line. Most of the lot consists of vacant grass fields. There is a moderate slope downhill towards the south, and steep slopes within the ravine.
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Figure 1. Aerial Photo (2016)
Site Application Review The applicant submitted for a development permit on January 23, 2017. The application was deemed incomplete on February 21, 2017 before being deemed complete on June 21, 2017. Completeness occurred within 150 days of submittal. The application was processed in accordance with Section 11.0400 and a decision is being rendered within 120 days of the application completeness date. Two preapplication meetings were held for this proposed land division, the first on April 20, 2016 (PAM 16-26000098) and the second on August 17, 2016 (PAM 16-26000246). The required early neighborhood notification meeting was held on September 17, 2016 at the Gresham Library. Documentation of the neighborhood meeting is included in the file copy. Request for agency comments was made on June 21, 2017. A public notice was mailed to property owners and residents within 300 feet of the boundary of the site as well as to representatives of the Gresham Butte Neighborhood Association on June 26, 2017. The applicant submitted an affidavit stating that the site was posted on June 22, 2017. Per Gresham Community Development Code (GCDC) Section 6.0201, the review of a tentative subdivision plan is subject to a Type II review procedure. The proposal includes development within two special purpose districts, both of which are reviewed under the Type II procedure. A Type II tree removal permit is also submitted concurrently. Per GCDC 11.0203(B)(2), an
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application that involves two or more procedures may be processed collectively under the highest numbered procedure required for any part of the application. Thus, this Subdivision, Tree Removal, and Environmental Overlay application was reviewed under the Type II procedure. Community Development Code standards are met as stated in the applicant’s narrative unless otherwise indicated in the following findings. Regulatory Findings Article 4 - Land Use District. The property is zoned LDR-7, and single-family residential homes are a permitted use. The proposed density of 5.96 dwelling units per acre falls within the 4.35/6.22 minimum/maximum density range for the LDR-7 district (Table 1). Table 1. Minimum and Maximum Permitted Density Range Net
X
Rate
Result
Minimum*
1.89
4.35
8.22 units
Maximum^
2.45
6.22
15.24 units
Proposed 14 units
*GCDC 3.0200 stipulates that both right of way (ROW) and HCA areas are subtracted from gross area when calculating the minimum density. {2.8 ac – (0.35 ac + 0.56 ac) = 1.89 ac} ^GCDC 3.0200 stipulates that only ROW dedication area is subtracted from gross area when calculating maximum density. {2.8 ac – 0.35 ac = 2.45 ac} The subdivision includes 15,088 sq. ft. (0.35 ac.) of ROW dedication and 24,493 sq. ft. (0.56 ac.) of habitat conservation area.
All base district lot dimension standards are eligible for a 20 percent reduction in order to accommodate an onsite density transfer requested by the applicant. The density transfer preserves habitat area by relocating development away from sensitive areas. Compliance with density transfer standards is discussed later in the Report under Section 5.0411(B)(3). This reduction is hereby referred to as the density transfer discount. The LDR-7 minimum lot width is 40 feet. Proposed lot widths range between 44 feet and 71 feet, exceeding the minimum requirement of 32 feet (accounting for the density transfer discount). None of the proposed lots are substandard with respect to lot width. The LDR-7 minimum lot depth requirement is 70 feet. Proposed lot depths range between 85 feet and 180 feet, exceeding the minimum requirement of 56 feet (accounting for the density transfer discount). None of the proposed lots are substandard with respect to lot depth. The LDR-7 minimum street frontage is 40 feet. Proposed lot street frontages range between 15 feet and 104 feet. Generally, the proposed lots meet the minimum 32-foot street frontage requirement (accounting for the density transfer discount). However, Lots 4, 5, and 6 are proposed as non-standard street frontage lots with Lot 5 being a flag
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lot. Findings are submitted by the applicant requesting the reduction of minimum street frontage in accordance with the parameters of GCDC Section 10.1520. As described later in this Report, a condition of approval is required to modify the lot configuration of Lots 4 through 6 to better comply with the street frontage reduction and rectilinear lot requirements. Per GCDC Section 5.0220(D), safe neighborhood standards will not apply to Lots 4 through 11 because they are located entirely within the Hillside environmental overlay. Only Lots 1, 2, 3, 12, 13, and 14 will be subject to safe neighborhood standards. Other base district standards are met as described in the applicant’s narrative. All lots will be subject to the standard setback requirements of Table 4.0130(E) (Table 2) and the 35-foot maximum building height. Lot 5 will comply with the reduced building height requirements for flag lots. Compliance with setbacks and height requirements will be reviewed at the time of building permit, and the standard required dimensions in effect at the time of building permit application will apply. Table 2. Setbacks (In feet) Front
Front or Streetside Porch
Front or Streetside Garage
Interior Side
Street Side
Rear, No Alley
Lots 1-3; 7-14
10
6
20
5
10
15
Flag Lots (Two Likely)
10
10
20
10
10
10
The residential compatibility (infill) standards of Section 4.0138(B) will apply to all lots except Lots 8 - 10, since the other lots are substandard with respect to LDR-7 minimum lot size and/or minimum street frontage. Compliance with Residential Floor Area Ratio (FAR) and supplemental building height setback will be required for those non-standard infill lots at building permit review. After accounting for the required lot reconfiguration (Condition of Approval #9) up to two of the lots will classify as non-standard lots that also meet the definition of a flag lot - having two distinct parts, a flag pole for access, and a flag large enough to accommodate the building envelope. Those lots will not be subject to the infill standards of Section 4.0138(B), but will instead be subject to those of Section 4.0138(C). A minimum 12-foot wide paved driveway will be required. The 3-foot landscape strip will be optional, since GCDC Sections 4.0138(C)(6)(c) and 9.0110(H) only require the landscape strip between the proposed pole and neighboring parcels that are not party to the proposed subdivision. Both adjacent lots are internal to the proposed subdivision. The effective lot area of each flag lot, subtracting the flag pole, will be approximately between 5,600 and 6,000 square feet. This meets the minimum requirement of 5,600 square feet, accounting for the density transfer discount. These will be permanent flag lots since there is no practical way to provide future street service.
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All area to the east is publicly owned and identified as open space to remain undeveloped for the foreseeable future, and adjacent neighborhoods to the south and north are already built to LDR-5 and LDR-7 densities. The infill standards of Section 4.0138(D) will not apply to any of these lots since they are not being constructed immediately adjacent to pre-existing single story single-family homes. Also, per Section 4.0138(B)(3), lots that are required to comply with the infill standards of Section 4.0138(B) are exempt from the infill standards of Section 4.0138(D). These standards are met with Condition of Approval #9 (Revised Layout Plan) and #24 (Lot Restrictions). Article 5 - Overlay Districts. The development site is affected by 101,138 square feet (2.32 acres) of Hillside Physical Constraint and 24,493 square feet (0.56 acres) of Habitat Conservation Area. Hillside Overlay. Eighty-three percent of the site lies within the hillside physical constraint overlay district. This section requires that a slope analysis map and a geotechnical report prepared by a registered civil engineer be submitted with the application. A slope analysis was submitted (Sheet G04) illustrating areas on the site with slopes exceeding 15 percent, and those with slopes exceeding 25 percent. Those areas sum to 54,717 square feet (1.26 acres) and 7,065 square feet (0.16 acres) respectively. None of the proposed buildings pads or street construction is located on slopes greater than 35 percent. A geotechnical report and technical memorandum prepared by Advanced Remediation Technologies, Inc., dated November 15, 2016 and May 20, 2017, were submitted. The reports were prepared by Lance A. Downs, PE, GE (OR #18510PE) Senior Principal Engineer. The general foundation design recommendations identified in the report include a restriction from developing in the portion of the 17-foot fill slope bordering the greenway area to the east. Shallow soil conditions may result in some limited settlement of shallow foundations. Limited over-excavation and/or structural fill placement, or other technologies, may be required in some areas to increase soil bearing capacity and strength, and to remove unsuitable soil from foundation areas. Wet weather work shall be performed on gravel work surface. Once clearing and striping is completed, proof-rolling the site with a loaded dump truck or other heavy vehicle is recommended. The report identifies general and structural fill placement specifications, as well as recommended cut and fill maximum slopes. Recommendations are also provided with respect to spread and continuous footings, seismic design, slabon-grade floors, settlement, lateral earth pressures, and pavement section. The November 2016 geotechnical report concludes that the site can be developed using standard construction practices given geotechnical engineer supervision during
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foundation preparation and their review of fill placement procedures to verify the execution of the design intent. The May 2017 memorandum prepared by Mr. Downs of Advanced Remediation Technologies provides additional clarification on findings and recommendations. It specifies that the 17 feet of non-structural fill that was placed on the site in the recent past affects proposed Lots 9, 10, 11, and 14. Otherwise, the site is generally underlain by medium stiff clayey silty soil. He affirms the conclusion of the November 2016 report that the site is suitable for residential development with conventional shallow-footing foundations. Modeling of slope stability for Lots 9 and 10 results in a static factor of safety well above the standard 1.5 required for design, and a seismic factor of safety above 1.1. The slopes are expected to be generally stable in their existing conditions. The memo confirmed that soil analysis of the site was based on soil samples collected from three shallow test borings conducted on October 3, 2016 by Western States Soil Conservation, Inc. (November 2016 GeoTechnical Study, Attachment A). However, no diagram or site plan showing the location of those borings is provided. Further analysis of the seismic hazard concludes that the site classifies as moderate (landslide possible), except that the southeast corner of the site has a landslide hazard of high (landslide likely). The report identifies the western portion of Lots 9 and 10 as landslide prone; however, in an email Mr. Downs confirmed that it is the eastern portion of Lots 9 and 10, abutting the greenspace, that is categorized as high landslide hazard (Exhibit D). The memo also gives further instruction on stormwater management. The applicant’s geo-technical report and memo were submitted to Timothy W. Blackwood, PE, GE CEG (OR #52838), of Hart Crowser for a third-party review. The memo dated July 21, 2017 documents the extent of compliance with GCDC Section 5.0220 - Hillside Overlay Development Standards. It evaluated the methodology, conclusions, and recommendations of the applicant’s geo-technical materials. This memo is hereby made part of the findings of this Staff Report and is included as Exhibit E. It found several aspects of the geo-technical report need more attention and recommends five conditions of approval, listed here: 1. A disclosure of financial interest in the project should be provided by the geotechnical engineer. 2. Boring locations should be provided so that the suitability of the exploration program can be assessed. The program should include enough explorations to adequately define the extents of the existing fills, evaluate slopes along Lots 5 through 10, and evaluate fills, cuts and walls if required. 3. Erosion Control Measures should be recommended by the geo-technical engineer, or they should review the civil plans for approval of the erosion control measures shown. 4. Vegetation removal should be addressed by the geotechnical engineer.
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5. A well supported assessment of the potential effects of the project onsite slopes should be included. The assessment should consider the effects of cuts, fills, walls, temporary and permanent slopes, grading, etc. Additionally, the report identifies three other deficiencies in the scope of the review that must be addressed by building permit submittal, and are therefore included as conditions of approval. They are: 1. Assessment of the cuts/potential wall on Lots 11 - 14. 2. A reassessment of the preliminary grading plan for severity of fills and cuts, especially as it relates to the 17 feet of pre-existing fill along the southern edge of the site. 3. An inspection schedule and erosion control plan minimum requirements shall be included. Per GCDC Section 5.0222(C), all areas with slopes of 35 percent or greater must be preserved by either private or public easement. Most of these slopes are located within the Habitat Conservation Area proposed to be dedicated as a tract to the City of Gresham. Private Steep Slope easements must be recorded for Lots 5, 9, and 10 for those areas identified in Sheets G05 and G06 as exhibiting slopes of 35 percent or greater (Condition of Approval #15). The applicant states in their narrative that there will be no site disturbance in areas exhibiting slopes of 15 percent or greater. However, the hillside slope analysis map (Sheet G05) in conjunction with the Construction Management Plan (Sheet G07) demonstrate that roadway grading, vegetation clearing and grading for building pads, and tree removal will occur in areas of the site with slopes exceeding 15 percent. Slope analysis data indicates that there are 67,136 square feet of areas exhibiting slopes of 15 percent or greater. Of this, approximately 11,075 square feet, or 16 percent of these slopes, are proposed to be cleared, graded, or otherwise disturbed. This complies with the cap of 35 percent (GCDC Section 5.0223(A)). Table 4. Area of Disturbance in Slopes 15 Percent or Greater Lot
6
7
8*
9
12
13*
14
ROW
Total
Approx. Area of Disturbance (Sq. Ft.)
600
400
2,400
600
1,200
2,400
800
2,675
11,075
*Includes building pad and driveway, front yard area.
The removal of 14 trees from a 121,853 square-foot lot does not meet the definition of clear cutting. There are approximately 89 trees on the lot prior to development, most are located within the Habitat Conservation Area that will remain undeveloped and be dedicated to the City. The tree density ratio prior to development, 0.73, is less than 1 per 1,000 square feet. A revegetation plan for those areas to be graded and striped as part of the utility and building pad construction shall be submitted with the public SD/TR/MIS 17-26000019 – Robbins Terrace Subdivision
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facilities building permit. The plan shall include details on native trees and shrubs to be planted in areas beyond 20 feet of the perimeter of proposed building pads, roadway, and driveways. The applicant has identified Teragan and Associates, a qualified arborist, to prepare the mitigation plan. Teragan shall consult with the engineer of record in drafting and finalizing the revegetation plan. These standards are met by Conditions of Approval #10 (Revised Construction Management/Grading Plan), #11 (Geo-Technical) and #12 (Revegetation Plan), and #15 (Private Steep Slope Easement). HCA Overlay: 5.0402 and 5.0403 - Applicability & Exempt Uses and Conditioned Activities. This overlay applies to all properties containing mapped Habitat Conservation Areas (HCA). The lot contains 21,180 square feet of moderate and 3,313 square feet of high HCA designated areas. Subdivisions are not an activity that is exempt from the HCA review. The proposal is subject to the standards of this section. There is no home construction proposed at this time. The applicant has opted for HCA disturbance applications to be submitted as necessary by homebuilders at the time of individual lot construction. Thus, no physical disturbance within the HCA is proposed as part of this subdivision application. All preliminary building pads are proposed to be situated outside of the Habitat Conservation Area. All grading and clearing activity related to road construction and utility installation will be located over 50 feet away from the HCA boundary. Maximum disturbance areas on an individualized lot basis are not being determined at this time. No mitigation plan is proposed. A revised construction management plan must be submitted showing the placement of required silt/erosion control and construction barrier fencing, including a detail of the construction barrier fencing. Do to the use of heavy equipment, the construction barrier fencing shall be as per the chain link fence detail, or another sturdy material as approved by the Manager. Orange construction fencing will not be permitted. The contractor shall be notified at the pre-construction meeting of the HCA requirements and instructed to prevent any work/disturbance beyond the HCA protection fence. This standard is met by Conditions of Approval #10 (Revised Construction Management Plan) and #27 (HCA and Tree Protection Fencing). 5.0404 - Prohibitions. This section prohibits the following in the HCA: •
The planting of invasive non-native or noxious vegetation;
•
Outdoor storage of materials;
•
New gardens, lawns, and structures other than those approved through this HCA permit;
•
Dumping of materials; and
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•
Grading, cut or fill that is not part of the approved HCA permit.
All grading to occur as part of this development permit shall be essential to achieving structural integrity of the roadway, utility infrastructure, and proposed building pads. No other grading shall occur within the HCA portion of the site that is not permitted to be disturbed. The applicant’s Sheet G07 lists the HCA prohibitions for reference by the contractors. A condition of approval will ensure that these standards are met. This standard is met by Condition of Approval #10 (Revised Construction Management/Grading Plan). 5.0411(B) - Methods for Avoiding HCA. This section indicates several methods for avoiding disturbance of the HCA. The applicant has opted to utilize flexible site design (onsite density transfer) as a method for avoiding impact to the Habitat Conservation Area. This method permits the transfer of up to 50 percent of the maximum density permitted on the HCA portion of the site to be transferred to the non-HCA portion. There is a total of 24,493 square feet of Habitat Conservation Area on the site. This equates to 0.56 acres. A density transfer of 50 percent of the maximum 6.22 dwelling units per acre permitted in the LDR-7 district results in a transfer of 1.74 units, which may round up to two units. The net non-HCA portion of the site is 1.89 acres in size (Subtracting HCA and right of way). The maximum density permitted on that portion of the lot would be 1.89 x 6.22, or 12 units. Twelve plus the additional two transferred units sum to a total maximum density in the non-HCA portion of the lot of 14 units. Fourteen units are proposed. The applicant does not request any of the lot level methods be applied. Eligibility and application of the setback flexibility and flexible landscaping requirements methods will be evaluated upon submittal of a separate HCA disturbance application(s) on a lot by lot basis. This standard is met. 5.0411(C)(1)(ii) and (iii) - Development within HCA. This section regulates the amount of incursion into the HCA that is permitted. No incursion into the HCA is proposed as part of the subdivision, road construction, utility installation, or building pad vegetation clearing/grading. The standards of these sections do not apply. 5.0411(D) - Utility Standards. Disturbance area limitations apply to new utilities and private connections to existing or new utility lines. The applicant proposes to place water line and other utility connections from the street frontage away from the HCA area. These standards do not apply. 5.0411(E)(1) - Mitigation Requirements for Disturbance in HCAs. To achieve the goal of reestablishing forested canopy that meets the ecological values and functions described SD/TR/MIS 17-26000019 – Robbins Terrace Subdivision
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in Section 5.0401(A) of this overlay, tree replacement and vegetation planting are required when development intrudes into an HCA according to the following standards. Either Mitigation Option 1 or 2 is required, based on which option results in more tree plantings. There is no mitigation requirement since there is no vegetation clearing or grading occurring within the HCA area. In case of inadvertent disturbance within the High HCA area, mitigation shall be required at the rate of 820 trees and 820 shrubs per acre. The species mix and size shall be as approved by the Manager. Trees and shrubs shall be a minimum of 12 inches in height. Trees shall be a combination of Western Red Cedar, Douglas Fir and Big Leaf Maple. Shrubs shall be a combination of Salal, Snowberry and Oregon Grape. Trees shall be planted at an average interval of 7 feet on-center. Shrubs shall be clustered in single species groups of four or less and be spaced from 8 feet to 10 feet on center. The fiveyear survival rate will be a minimum of 500 trees per acre and 650 shrubs per acre. This standard is not applicable unless there is inadvertent disturbance within the high or moderate HCA areas. Condition of Approval #7 (Inadvertent Disturbance) relates to this standard. 5.0411(E)(7) - Invasive Vegetation. The applicant is encouraged to voluntarily remove invasive vegetation present in the immediate 10-foot perimeter of the proposed building pads. This standard is not applicable. Recommendation A is included at the end of this Report. 5.0411(F)(2) - Subdivisions in HCA. The applicant states in their narrative that the proposal is to subdivide and develop the property. Over the course of their entire submittal narrative, they make clear that the intent is to only develop the road, utility infrastructure, tree removal, and building pad vegetation clearing and grading. The development does not include home construction. The lots will be sold off individually and will apply for residential construction at later dates. Those lots with HCA designation will require a separate Habitat Conservation Area development permit application if home construction will encroach into the restricted area. Thus, the applicant has chosen to proceed with Mitigation Option 2, deferred mitigation, as specified in Section 5.0411(F)(2)(a)(ii). The applicant complies with the requirement to place at least 80 percent of all HCA on the site in a separate unbuildable tract since Moderate HCA comprises most HCA on the parcel. A total of 80 percent of the HCA (19,600 square feet) is being dedicated to the City of Gresham as Tract A. This includes 100 percent of the High HCA (3,312 square feet) and 77 percent of the Moderate HCA (16,287 square feet). Note that the applicant states on their narrative that 93 percent of the moderate HCA area is being dedicated, or 19,697 square feet. This is not shown to be the case on Sheet G06 and exceeds the stated total quantity of dedication. Drawings and other sections of the applicant’s
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narrative indicate that 19,600 square feet is being dedicated, including 3,313 square feet of high HCA dedication. No reduced rear setback is requested or granted as part of this approval; it is retained as the LDR-7 district standard 15 feet. The applicant intends to deed the tract to the City of Gresham, or if necessary, to Metro or a private non-profit with the mission of land conservation. The City will accept the dedication and the tract must be deeded prior to the recordation of the plat. A draft of the transfer of deed documents must be submitted with the final map application. Table 3. HCA Proportions on Buildable Lots Lot
Size (ft.)
Percent of Lot
5
1,540
22
6
840
15
7
877
13
8
335
4
9
560
8
10
741
10
This standard is met with Condition of Approval #14 (HCA Tract Dedication). 5.0413 - Variances. Variances may be granted when strict compliance with the standard HCA provisions result in unreasonable hardship. The requirements of the HCA overlay may be varied to avoid such instances. The applicant does not propose any variances. This standard is not applicable. 5.0414 - Map Administration and HCA Verification. This section provides mapping standards if the applicant chooses not to adopt the HCA boundary as mapped by the City. The HCA area will be marked and fenced off on the field prior to commencement of grading and vegetation stripping. The applicant accepts the HCA boundary as drawn by the City, Basic Verification Approach 1. The HCA area will be fenced off using the standard chain link fence detail, Exhibit F. These standards are met with Conditions of Approval #6 (HCA Disturbance Area), #10 (Revised Construction Management/Grading Plan) and #27 (HCA and Tree Protection Fencing). 5.0415 - Consistency and Relationship with Other Regulations. Eighty-three percent of the site is within the Hillside Constraint District. A Soils and Engineering Report has been provided. The recommendations within the Soils and Engineering Report are to be followed at the time of building construction.
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These standards are met by Condition of Approval #11 (Geo-Technical). 5.0415(D) - Development Near Regulated Streams. There is no regulated stream present on the lot. This standard is not applicable. 5.0416 - Violations. As cautionary information, actions that violate the HCA regulations, such as removing habitat without having a required HCA permit, are subject to the abatement and penalty provisions of Section 11.0600 of the Development Code. If the applicant violates the HCA regulations during the house construction process, these standards will apply. This standard is not applicable at this time but will be if the provisions of the HCA are violated. Condition of Approval #7 (Inadvertent HCA Disturbance) relates to this standard. Article 6 - Land Divisions. Lot design standards are met as demonstrated by the applicant, except as described here. Staff generally concurs with the applicant’s assessment that proposed lots are as rectilinear as possible given site topography and parent lot configuration except for proposed Lots 4 through 6. While the shared side lot lines between Lots 3 and 4 and between 6 and 7 are not precisely radial to the right of way frontage edge, they are perpendicular to the right of way center line and are thus acceptable. The configuration of Lots 4 through 6 include one shared side lot line that is severely skewed from the radial and must be corrected. Additionally, better compliance with the street frontage reduction standards, as described in findings for Section 10.1520 below, necessitates this change. A preferred alternative as well as alternates are included for the applicant’s reference in redrawing these lots (Exhibit F). The final map application shall include a plat layout based on the preferred alternative, or one that demonstrates compliance with these criteria: 1. The shared side lot lines shall be rectilinear (radial to the street right of way, either at the edge of the right of way or centerline). 2. At least one of the three lots shall have a minimum 32-foot street frontage. 3. Effective lot areas of at least 5,600 square feet. 4. The building pads shall not be located within the Habitat Conservation Area and must be setback a sufficient distance from the HCA so that no disturbance will occur during grading and vegetation for a distance of at least 10 feet. The applicant proposes building pads of approximately 30 by 40 feet, not including the front yard and driveway approach areas. Table 3 shows this is sufficient for ensuring no foreseeable difficulties for reason of topography, HCA restrictions, or other conditions in securing building permits to build on each of the proposed lots.
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Section 6.0010 Lot arrangement is met. The rectilinear lots are of sufficient size and depth as to not cause foreseeable difficulties with acquiring building permits. Lots 8, 9, 12, 13 and 14 may need to be significantly regraded under the direction of the geotechnical engineer in order to achieve a structurally sound building pad. Lots 10 and 11, although relatively flat, may need over-excavation and placement of structural fill or as recommended by the geotechnical engineer in order to ensure adequate load bearing capacities. These measures are within the scope of conventional single-family residential construction. Section 6.0011 - Residential District Lot and Parcel Configuration Standards are mostly met. The subdivision includes three corner lots, 11 non-standard lots (primarily with respect to lot size), 11 irregular/non-rectangular shape lots, and 12 rectilinear shape lots. Lot configuration revisions outlined above will ensure that all 14 lots are platted as rectilinear lots. The irregular shaped lots are permitted on the basis that their nonrectangular shape is a product of either the required right of way edge design and/or the curvilinear edge of the City mapped Habitat Conservation Area. This standard is met with Conditions of Approval #9 (Revised Layout Plan) and #24 (Lot Restrictions). Recommendation B (Rear Lot Lines Lots 5 through 10) addresses this standard. Article 9 - Common Requirements. The applicant’s findings with regards to the applicable sections of Article 9.0000 are accepted as described in the narrative, except as described here. 9.0100 - Buffering and Screening. Section 9.0110(H) specifies requirements for buffering of flag lots. Development of new residential structures on flag lots shall provide a landscaped area around the perimeter of the flag portion of the flag lot. The flag pole and lot lines that are internal to the original land division that created the flag lot, or adjacent to an alley, are exempt from this requirement (see Figure 9.0110(H)). Lot 5 is proposed as a flag lot and a second flag lot will most likely be required to comply with Condition of Approval #10 (Revised Layout Plan). The only property line shared with property not party to the proposed subdivision will be those lot lines to the north. A 5-foot vegetated landscape strip shall be provided along this property line. The revegetation plan submitted with the final plat review shall include the placement, quantity, species, spacing, size at planting, and proposed irrigation method for the vegetated buffer strip, as well as a labeled outline of the 5-foot wide buffer area. This standard is met by Conditions of Approval #12 (Revegetation Plan) and #24 (Lot Restrictions).
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9.0500 - Grading and Drainage Plans. See other staff comments on compliance with this section. These standards are met by Conditions of Approval #3 (Public Facilities), #4 (PreDesign Meeting), #5 (Site Construction), #11 (Geo-Technical), #13 (Civil Engineer Construction Drawing Set). 9.0800 - Parking Standards. Parking standards will be met. Parking will be provided through a combination of 20-foot minimum length concrete driveway and/or garage parking. Compliance will be assessed at the building permit review stage. This standard will be met. 9.1032 - Tree Removal and Protection. This section contains regulations for the removal and/or protection of regulated size trees (8-inch diameter at breast height (DBH)). A tree protection zone shall be installed with protective fencing around all regulated, required, and significant trees/significant grove to remain onsite and shall be located in a radius from the tree at a rate of 1 foot of horizontal distance from the tree for each 1 inch diameter of tree, or as determined by a Certified Arborist. There are 14 regulated trees proposed to be removed out of approximately 89 presently located on the site. The construction management plan (Sheet G07) shows that tree protection fencing will be installed between the proposed grading area and both the greenspace to the east and the single-family homes to the north. A detail of the proposed fencing is not included. The plan notes but does not illustrate the critical root zones of Trees #12, #13, #17, #18, and #19. These trees are meant to be preserved. A revised construction management plan must include a detail of the proposed fence that complies with the minimum requirements specified in this section. It must also include the outlines of the tree protection zones for these trees and any other regulated size trees within the greenspace area whose protection zones extend into the proposed grading area. Section 9.1032(B) requires that a certified arborist prepare the tree protection plan for those trees with protection zones within the grading area. Trees #12, #13, and #19 will have grading occurring within the protection zone. Thus, the tree protection measures of the construction management plan must be stamped or signed by a registered arborist. The arborist shall be consulted about specific preservation/protection measures necessary to ensure tree protection. The construction management plan shall be revised to include the following tree protection instructions to contractors, and/or instructions as recommended by the certified arborist. 
No machinery repair or cleaning shall be performed within 10 feet of the Tree Protection Zone of any trees identified for protection.

Digging a trench for placement of public or private utilities or other structure within the critical root zone of a tree to be protected is prohibited.
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A Certified Arborist must be present when grading within 29 feet of Tree #12, 31 feet of Tree #13, 26 feet of Tree #17, and 46 feet of Tree #19.
No soil compaction or removal of vegetation or tree branches within the Tree Protection Zone shall be allowed during construction, except as outlined by a Certified Arborist in a submitted Tree Protection Plan.
Trees #12 (29-inch Doug Fir), #13 (31-inch Doug Fir), #17 (26-inch Doug Fir), #18 (17-inch Cedar), and #19 (46-inch Cedar) are slated for preservation. Home footprints must be located no closer than 10 feet from the trunk of these trees and they may not be removed by future applicants by exemption request. If removal is requested, a Type I or Type II tree removal permit will be required depending on the reason for removal. There are no registered significant trees on the site or on abutting sites. These standards are met by Conditions of Approval #10 (Revised Construction Management/Grading Plan), #16 (Tree Protection), and #24 (Lot Restrictions). 9.1023 - Street Tree Planting. Residential subdivision developments are required to plant one tree per 30 feet of lineal frontage, discounting driveways, or pay into the tree fund for trees whose planting is infeasible due to site constraints, per Section 9.1033(G). Street trees cannot be planted because of the reduced Hillside street cross section which does not include a planter strip. The site constraint in this case is topography. The applicant agrees in their narrative to make the contributions as necessary. A contribution of $300 per tree is the current fee amount. The subdivision includes 578 lineal feet of non-driveway street frontage. An in-lieu-fee of $6,000 ($300 x 20 required street trees not planted) is required prior to final plat approval. This standard is met with Condition of Approval #8 (Street Tree In-Lieu). Article 10 - Supplementary Development Regulations. The development includes a request for reduction of minimum street frontage. It does not include any request for variance. 10.1520 - Reduction of Minimum Frontage. Staff concurs with the applicant’s request for a reduction in minimum frontage, except that at least one of the proposed Lots 4, 5, and 6 must be reconfigured to meet the minimum street frontage of 32 feet (accounting for the density transfer discount). As proposed, there is 50 feet of frontage allocated amongst three lots. Fifty feet is sufficient for at least one lot to meet the minimum 32foot requirement. While there is only enough lineal frontage to support one lot in that corner of the subdivision, there is enough square footage available for three. Thus, two of the lots will not have sufficient frontage to meet the minimum frontage requirement. Two of the proposed lots qualify for a reduction of the minimum street frontage due to steep hillside topographical constraints, as well as lack of opportunity for future street connectivity to the east due to three constraints: a) Habitat Conservation Area designation and proposed dedication, b) presence of a ravine with slopes greater than SD/TR/MIS 17-26000019 – Robbins Terrace Subdivision
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35 percent, and c) build out of adjacent single-family residential neighborhoods within LDR-7 and LDR-5 densities and restriction of development to the east which is publicly owned open space woodland that is intended to remain undeveloped. The final plat shall incorporate a lot configuration revision for Lots 4 through 6 that complies with these criteria: a. Rectilinear Lots. The shared side lot lines shall be rectilinear (defined as perpendicular or radial to the street right of way, either the edge of the ROW or centerline). b. Minimum Street Frontage. At least one of Lots 4, 5, and 6 must be revised to comply with the minimum 32-foot street frontage requirement. c. Minimum Lot Size. The effective lot area of the proposed flag lots, subtracting the flag pole, must be at least 5,600 square feet, accounting for the density transfer discount. d. HCA Disturbance. The building pads for the revised pads shall not be located within the Habitat Conservation Area and must be setback a sufficient distance from the HCA so that no disturbance will occur during grading and vegetation clearing. These standards are met with Condition of Approval #9 (Revised Layout Plan). Appendix 5.000 – Public Facilities. The proposed subdivision must provide adequate water, sewer, stormwater, and transportation facilities. Development engineering comments address compliance with these standards and identify conditions of approval necessary to ensure compliance. These standards are met by Conditions of Approval #3 (Public Facilities), #4 (PreDesign Meeting), #5 (Site Construction), #11 (Geo-Technical), #13 (Civil Engineer Construction Drawing Set), #17, (Septic Decommissioning), #18 (General Utility Easement), #19 (Water Well), #20 (Water Main Extension), #21 (Streets), #22 (Curb & Sidewalk Connectivity), and #25. II. AGENCY COMMENTS ADDRESSING COMMENTS FROM: Carrie Osborn, Planning Technician II DATE: June 27, 2017 For the plat, please update the streets as follows: • East/west street: SW 22ND TERRACE (Lot 1 to Lot 6) • North/south street: SW WALLULA LANE (Lot 7 to Lot 10) The existing home located on proposed Lot-5 will require an address change after the new streets have been constructed. Addresses for the lots will be available after the final plat has been recorded with Multnomah County and building permits have been submitted. Addresses will be assigned in accordance SD/TR/MIS 17-26000019 – Robbins Terrace Subdivision
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with the City of Gresham Street Naming and Property Numbering Guidelines of Gresham Community Development Code Appendix 13. Additionally, the US Postal Service requires that mail delivery to all new developments be centralized by using centralized box units. It is the responsibility of the developer/builder to purchase, install and maintain the mail receptacles. A handout from the Post Office with more information is available upon request. The applicant and/or representative may contact the Addressing Coordinator at 503-618-2809 with any questions or concerns. FIRE COMMENTS FROM: Kyle Stuart, Gresham Fire DATE: June 30, 2017 NOTE: Building permit plans shall include a separate “FIRE ACCESS AND WATER SUPPLY PLAN” indicating all of the following: 1. Residential homes up to 3,600 square feet require a minimum of 1,000 gpm fire flow. Residential homes from 3,601 - 4,800 square feet require 1,750 gpm fire flow. The fire flow increases from there. Fire Flow forms will be required to be filled out during the permit process. OFC App B 2. Each building is required to be sprinklered if the code's minimum water flow is not available. OFC App B 3. Fire Access roads are required to be a minimum of 20 feet wide. Roads 20 to 26 feet wide do not allow parking on either side and require NO PARKING FIRE LANE marking/signage on both sides. Fire Access roads 26 to 32 feet allow parking on one side only and require the NO PARKING FIRE LANE marking/signage on one side. OFC 503.3 4. The turning radius for all emergency apparatus roads shall be: 28 feet inside and 48 feet outside radius. This must be indicated. OFC 503.2.4 5. All Fire Department access roads shall be constructed and maintained prior to and during construction. OFC 1410 6. Access roads shall support an imposed load of at least 75,000 lbs. Provide an engineer’s letter stating that requirement was met during subdivision final. OFC 503 & APP D-102.1 7. Fire access turn arounds are to be at the dead-end side of the fire access. OFC D103.4 8. Each public or private fire hydrant used for fire flow for this property shall have a 5-inch Storz adapter with National Standard Threads installed on the 4½-inch fire hydrant outlet. The adapter shall be constructed of high-strength aluminum alloy, have a Teflon coating on the seat and threads, and use a rubber gasket and two (2) set screws to secure it in place. The adapter shall be provided with an aluminum alloy pressure cap. The cap shall be attached to the hydrant barrel or Storz adapter with a cable to prevent theft of the cap. Adapter shall be Harrington HPHA50-45NHWCAP or equal approved by Gresham Fire.
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9. Where a fire hydrant is installed, the access road must be a minimum of 26 feet wide for a minimum of 40 feet. OFC APP D-103.1 10. Put a note on the plans stating “All watermains and hydrants shall operate prior to construction materials arriving on site.” A hydrant must be within 600 feet of the furthest point on each house. OFC 1412.1 & 507 DEVELOPMENT ENGINEERING COMMENTS FROM: Jesse Davies, Development Engineering Specialist DATE: July 20, 2017 The project area is located at 1300 SW 21st Ter. in the Low Density Residential - 7 (LDR-7) land use district and partially within a hillside constraint overlay. The applicant proposes a 14-lot subdivision with an extension of SW 22nd Terrace to the east and then south connecting to SW 23rd Terrace. The following comments are from Development Engineering and refer to the plans submitted by R&T Engineering LLC on June 19, 2017. A5.000 GENERAL Design and construction of all public facility improvements shall be in conformance with applicable sections of the Gresham Community Development Code (GCDC), Gresham Public Works Standards (PWS), Water Quality Manual (WQM) and Gresham Revised Code (GRC). If the land use application is approved, the applicant shall schedule a pre-design meeting with Jesse Davies, Development Engineering, at 503-618-2395 prior to construction plan submittal to discuss technical requirements, design and construction schedules, and to review processes. With construction plan submittal, the applicant will provide an engineer’s estimate of the cost of public improvements (including private onsite stormwater detention and water quality systems), enter into an agreement with the City of Gresham for plan review and inspection services, and pay deposits based on the estimate. The applicant will provide a performance bond based on 110 percent of the engineer’s estimate. Approvable public facilities construction plans and performance bond are required prior to plat approval. Approved plans are valid for one year, and all public improvements must be completed within two years of the Notice to Proceed unless otherwise approved by the Manager. Any project that includes construction of public facilities must comply with City of Gresham survey standards. Plans must reference City of Gresham benchmark, NGVD 1929, 1947 adjustment. Coordinates must be based on Lambert State Plane Coordinate System, Oregon North Zone. Basis of bearing for all measurements must be taken from the City Control Network. Control Points can be found at www.GreshamOregon.gov/Maps/. Plans that reference Multnomah County or City of Portland control points are not approvable.
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A5.100: SANITARY SEWER FACILITIES City records show an existing 8-inch diameter PVC mainline that terminates at the end of SW 22nd Terrace and an 8-inch diameter PVC mainline that travels though the center of SW 23rd Terrace. A new sanitary mainline will need to be extended from where it terminates in SW 22nd Terrace through the proposed subdivision as needed for the development. New laterals will need to be constructed to serve each newly created lot and the existing house. Laterals may be extended from the mainline in SW 23rd Terrace to serve lots along this frontage. City records indicate the existing home at 1300 SW 21st Terrace has no sewer connection. It is assumed the existing house is still on a septic system. This system shall be decommissioned prior to plat approval. The applicant will need to contact the City of Portland about decommissioning the septic tank. More information about septic decommissioning can be found at www.PortlandOregon.gov/bds/38123. A5.200: SURFACE WATER MANAGEMENT SYSTEMS The site lies in the Johnson Creek drainage basin. Per the GCDC, onsite detention and water quality treatment are required for developments that add or replace 1,000 square feet or more of the existing surface with impervious area. There is an existing 12-inch HDPE storm line that extends to the end of SW 22nd Terrace. This line can be extended through the proposed subdivision as needed. Detention requirements for stormwater facilities must comply with the current Public Works Standards. The minimum requirements for detention are described in Section 4.02 and design guidance can be found in Section 4.08 of the PWS. The use of onsite stormwater systems such as rain gardens, planter boxes, pervious pavement, and other green development practices as described in the City’s Green Development Practices Manual should be given preference in satisfying water quality requirements. Please use this Manual for guidance in the final green development design. Sizing calculations provided in the Green Development Practices Manual must be adjusted for this site’s conditions. A final storm report as well as construction plans for the private water quality treatment and detention facilities must be submitted for review at the time of building permit submittal. All subdivision level water quality and detention facilities must be public. An NPDES 1200-C permit is required from the Oregon Department of Environmental Quality (DEQ) as the land disturbance exceeds one acre. Application and information is available at: www.deq.state.or.us/wq/wqpermit/StormWaterFeesTable.htm. Completed application materials are submitted through the City of Gresham. All grading, drainage, and construction activities shall be in accordance with the geotechnical report submitted by Advance Remediation Technologies, Inc. or City of Gresham standards where more stringent.
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A5.300: WATER FACILITIES The site is located in the South Hills service level with an average static pressure of 86 psi. Available fire flow is 1,100 gallons per minute at 57 psi residual pressure. The developer’s engineer is responsible to ensure the water system is adequate for the customer’s needs. State plumbing code requires private pressure reducing valves (PRV’s) on homes where the system pressure exceeds 80 psi. Each new home shall have a private PRV installed behind the meter. City records indicate that the existing house is currently not served by public water. It is assumed the house utilizes an onsite well. Proof of well abandonment or its location on an adjacent site shall be provided prior to final plat approval. There is an 8-inch ductile iron water main in SW 22nd Terrace and an 8-inch ductile iron water main in SW 23rd Terrace. The 8-inch mainline in SW 22nd Terrace shall be extended and “looped” through to the mainline in SW 23rd Terrace. New 1-inch services and ¾-inch meters will be needed for each newly created lot and the existing house. Fire flow requirements are determined by the Fire Department and not by Development Engineering. Only the Fire Marshal or the Building Official can reduce or increase these requirements. A5.400: STREETS SW 22nd Terrace and the new north-south street are classified as a Local Transitional street. The standard right of way width and improvements are shown in the following cross section. Per Section 6.02.02 of the Public Works Standards, roadways in hillside overlay zones are allowed to have reduced ROW widths. The full width of the continuation of SW 22nd Terrace and the new north-south street shall be dedicated with 40 feet of right of way. Both streets shall be improved to provide 28 feet of pavement with 6-inch curbs and 5-foot sidewalks on either side of the streets. Future Street Plan (FSP) #59 shows SW 22nd Terrace connecting with SW Binford Lake Parkway. The plan to connect to SW 23rd Terrace as proposed is substantially compliant with the FSP and no FSP Modification would be needed.
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SW 23rd Terrace is classified as a Local Queuing street. The standard right of way width and improvements are shown in the following cross section. Per Section 6.02.02 of the Public Works Standards, roadways in hillside overlay zones are allowed to have reduced ROW widths. SW 23rd Terrace can remain with a 40 foot ROW and 28 feet of pavement. Frontage improvements should include a new curb-tight 5-foot walk. Existing curb return and pavement dead-end on the north side of SW 23rd Terrace at SW Binford Lake Parkway shall be removed and replaced with standard curb and sidewalk, as proposed. No additional dedication is required.
The long chord must be dedicated for all street intersections based on the curb return radius of the lower classification street. ADA-compliant curb ramps must be installed at the intersection of the new north-south street and SW 23rd Terrace. Per Section 6.02.14 of the PWS, street lighting with LED fixtures must be provided on all public street frontages at an appropriate spacing based on each street’s classification. A street light plan, including a preliminary plan showing the connection to Portland General Electric’s (PGE’s) current system must be submitted with the construction plans submitted at the time of building permit review. EASEMENTS AND OTHER General Utility Easements shall be provided along all street frontages. All easements on the property, public and private, must be shown on the plans. Easements on adjacent property that benefit the project site must also be shown. CHARGES AND FEES System Development Charges (SDCs) and connection fees for parks, transportation, stormwater, water and wastewater are due to the City of Gresham prior to building permit SD/TR/MIS 17-26000019 – Robbins Terrace Subdivision
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issuance or at the time of connection for the existing house. Allocated capacity (credit) for the existing home, if demolished, will be provided to one lot in the subdivision to be determined by the developer. For required public improvements, the developer will enter into a contract to pay City staff for plan review and inspection services. A deposit will be paid based on the engineer’s estimate, and these services will be paid for at actual rates. A guarantee of completion will be required for 110 percent of the public improvement estimate. SUMMARY OF DEVELOPMENT ENGINEERING COMMENTS Findings submitted under each proceeding code section are generally consistent with section A5.000 of the Community Development Code and the Public Works Standards. Recommended conditions will ensure that the Community Development Code and the Public Works Standards are met and adequate public facilities to serve this development are constructed. III. PUBLIC COMMENTS Two public comments were received by the July 10, 2017 deadline. Comments submitted by the Land Use Chair of the Gresham Butte Neighborhood Association expressed concern about the quality of the geotechnical report submitted, specifically with regards to the number and location of bore holes, adequacy of grading plan, erosion control along the eastern edge of grading adjacent to the ravine, and the need for retaining walls. The comment also calls out the lack of connection of the proposed water main line to facilitate more consistent water pressures. Mr. Aaron Eder submitted concerns about sidewalk connectivity and water line continuity. Staff Response: The geotechnical report was submitted for third party review and was found to be generally compliant with Development Code standards. There were some deficiencies identified which are being addressed by Condition of Approval #11 (GeoTechnical). The engineer will be required to identify the location of the three bore holes and to perform additional site explorations as needed to adequately define the extents of the existing fills, evaluate slopes along Lots 5 through 10, and evaluate fills, cuts and walls if required. Condition of Approval #20 (Water Main Extension) requires the applicant to extend the waterline through to the mainline in SW 23rd to complete the loop. Condition of Approval #23 (Sidewalk and Curb Connectivity) requires that the applicant fully connect the proposed sidewalk and curb to the existing terminus point south of the site. IV. DECISION The proposal is approved with conditions for a 14-lot single-family residential subdivision, the removal of 14 regulated trees, a Hillside street extension, dedication of 0.45 acres of Habitat Conservation Area, and zero feet of Habitat Conservation Area (HCA) disturbance.
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V. CONDITIONS OF APPROVAL 1. Effective Period. This approval is valid for a period of two years from the date the decision becomes final (August 28, 2019 if not appealed). 2. Final Map Application. Before the end of the effective period of the tentative plan approval, submit to the City of Gresham Permit Center 10 paper copies of the final plat, along with the required fee, application, and documents required by Section 6.0403. The final plat submittal shall conform to Sections 6.0401 through 6.0404 and shall comply with the approved preliminary plan, conditions of approval, and applicable requirements of the Development Code. A one-year extension as permitted under Section 11.0106 is available. The proposed land division will be void if a final map application is not submitted. GENERAL 3. Public Facilities. The applicant shall provide adequate public facilities and services including access, drainage, water and sanitary sewer, as applicable, per all applicable sections of Appendix 5 of the Community Development Code and Public Works Standards. 4. Pre-Design Meeting. The applicant shall schedule a pre-design meeting with Jesse Davies, Development Engineering Specialist, at 503-618-2395 prior to construction plan submittal to discuss permit processes, technical requirements, design and construction schedules, and plan review processes. 5. Site Construction. All grading, drainage, and construction activities shall be in accordance with the geotechnical report submitted by Advance Remediation Technologies, Inc. or City of Gresham standards where more stringent. 6. HCA Disturbance Area. There shall be no disturbance within the Habitat Conservation Areas on the site. The lead contractor and sub-contractors must be informed of this restriction and instructed not to clear, strip, grade, fill, stage, or otherwise disturb areas located beyond the HCA boundary fencing. 7. Inadvertent HCA Disturbance. In case of inadvertent disturbance within the High HCA area, mitigation shall be required at the rate of 820 trees and 820 shrubs per acre. The species mix and size shall be as approved by the Manager. Trees and shrubs shall be a minimum of 12 inches in height. Trees shall be a combination of Western Red Cedar, Douglas Fir and Big Leaf Maple. Shrubs shall be a combination of Salal, Snowberry and Oregon Grape. Trees shall be planted at an average interval of 7 feet on-center. Shrubs shall be clustered in single species groups of four or less and be spaced from 8 feet to 10 feet on center. The five-year survival rate will be a minimum of 500 trees per acre and 650 shrubs per acre. TO BE MET PRIOR TO FINAL PLAT APPROVAL 8. Street Tree In-Lieu Payment. An in-lieu-fee of $6,000 ($300 x 20 trees) is required prior to final plat approval. 9. Revised Layout Plan. Submit a revised subdivision configuration that reconfigures Lots 4, 5 and 6. Refer to Exhibit D (Redlines).
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a. Rectilinear Lots. The shared side lot lines shall be rectilinear (defined as perpendicular or radial to the street right of way, either at the edge of the ROW or centerline). b. Minimum Street Frontage. At least one of Lots 4, 5, and 6 must be revised to comply with the minimum 32-foot street frontage requirement. c. Minimum Lot Size. The effective lot area of Lot 5, subtracting the flag pole, must be at least 5,600 square feet, accounting for the density transfer discount. d. HCA Disturbance. The building pads for the revised pads shall not be located within the Habitat Conservation Area and must be setback a sufficient distance from the HCA so that no disturbance will occur during grading and vegetation clearing for a distance of at least 10 feet. 10. Revised Construction Management/Grading Plan. A revised construction management plan must be submitted showing the placement of required silt/erosion control and construction barrier fencing, including a detail of the construction barrier fencing. All grading to occur as part of this development permit shall be essential to achieving structural integrity of the roadway, utility infrastructure, and proposed building pads. No other grading shall occur within the HCA portion of the site that is not permitted to be disturbed. Do to the use of heavy equipment, the construction barrier fencing shall be as per the chain link fence detail. Orange construction fencing will not be permitted. The construction management plan shall be revised to include the following tree protection instructions to contractors, and/or instructions as recommended by the certified arborist.
No machinery repair or cleaning shall be performed within 10 feet of the Tree Protection Zone of any trees identified for protection.
Digging a trench for placement of public or private utilities or other structure within the critical root zone of a tree to be protected is prohibited.
A Certified Arborist must be present when grading within 29 feet of Tree #12, 31 feet of Tree #13, 26 feet of Tree #17, and 46 feet of Tree #19.
No soil compaction or removal of vegetation or tree branches within the Tree Protection Zone shall be allowed during construction, except as outlined by a Certified Arborist in a submitted Tree Protection Plan.
11. Geo-Technical. a. A disclosure of financial interest in the project should be provided by the geotechnical engineer. b. Boring locations should be provided so that the suitability of the exploration program can be assessed. The program should include enough explorations to adequately define the extents of the existing fills, evaluate slopes along Lots 5 through 10, and evaluate fills, cuts and walls if required.
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c. Erosion Control Measures should be recommended by the geo-technical engineer, or they should review the civil plans for approval of the erosion control measures shown. d. Vegetation removal should be addressed by the geotechnical engineer. e. A well supported assessment of the potential effects of the project onsite slopes should be included. The assessment should consider the effects of cuts, fills, walls, temporary and permanent slopes, grading, etc. f. Assessment of the cuts/potential wall on Lots 11 - 14. g. A reassessment of the preliminary grading plan for severity of fills and cuts, especially as it relates to the 17 feet of pre-existing fill along the southern edge of the site. h. An inspection schedule and erosion control plan minimum requirements shall be included. 12. Revegetation Plan. Submit a revegetation plan for those 15 percent and greater sloped areas that will be cleared and/or graded and that are located beyond the front yard and building pads. It must show quantity, species, size at planting, location, and proposed irrigation during establishment period. Teragan shall consult with the engineer of record in drafting and finalizing the revegetation plan. The revegetation plan submitted with the final plat review shall include the placement, quantity, species, spacing, size at planting, and proposed irrigation method for the vegetated buffer strip, as well as a labeled outline of the 5-foot wide buffer area. 13. Civil Engineer Construction Drawing Set. Submit a public facilities construction drawing set prepared by a registered civil engineer showing proposed street, water, sewer, and stormwater infrastructure improvements. The grading plan and/or construction management sheet in the set shall include the following instructions to the contractor: a. The following activities are PROHIBITED in the Habitat Conservation Area: •
The planting of invasive non-native or noxious vegetation.
•
Outdoor storage of materials or equipment staging.
•
Dumping of materials and spoils piles.
•
Grading, cut or fill.
14. HCA Tract Dedication. The City will accept the dedication and the tract must be deeded over to the City prior or concurrent to the recordation of the plat. A draft of the transfer of deed documents must be submitted with the final map application. 15. Private Steep Slope Easement. Private Steep Slope easements must be recorded for Lots 5, 9, and 10 for those areas identified in Sheets G05 and G06 as exhibiting slopes of 35 percent or greater.
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16. Tree Protection. The tree protection measures of the construction management plan must be stamped or signed by a registered arborist. The arborist shall be consulted about specific preservation/protection measures necessary to ensure tree protection. 17. Septic Decommissioning. The existing sanitary sewer system shall be decommissioned and proof provided prior to final plat approval. 18. General Utility Easement. Six-foot wide General Utility Easements shall be provided along all street frontages. 19. Water Well. Proof of well abandonment or its location on an adjacent site shall be provided prior to final plat approval. 20. Water Main Extension. The 8-inch mainline in SW 22nd Terrace shall be extended and “looped” through to the mainline in SW 23rd Terrace. 21. Streets. SW 22nd Terrace shall be extended to the east and a new north-south street constructed that connects to SW 23rd Terrace. Both streets shall be constructed to modified Local Transitional Streets standards requiring 40 feet of right of way, 28 feet of pavement, 6-inch curbs, 5-foot sidewalks and streetlights. SW 23rd Terrace shall be widened to modified Local Queuing Street standards requiring the construction of a 5-foot sidewalk behind the existing curb. 22. Curb & Sidewalk Connectivity. The existing curb return and pavement dead-end at the intersection of SW 23rd Terrace and SW Binford Lake Parkway shall be removed and replaced with standard curb and sidewalk. Existing curb return and pavement dead-end on the north side of SW 23rd Terrace at SW Binford Lake Parkway shall be removed and replaced with standard curb and sidewalk, as proposed. The sidewalk shall be completed off-site as necessary to extend to the existing terminus west of the fire hydrant on SW Binford Lake Parkway. 23. Final Plat Street Formatting. For the final plat, include the following: a. East/west street: SW 22ND TERRACE (Lot 1 to Lot 6). b. North/south street: SW WALLULA LANE (Lot 7 to Lot 10). c. Remove all periods from street names. For example, N.E. COUCH ST should appear as NE COUCH ST. d. Spell out all street suffixes. For example, NE COUCH ST, should appear as NE COUCH STREET. TO BE MET PRIOR TO BUILDING PERMIT APPROVAL 24. Lot Restrictions a. Lot 5 must comply with the infill standards including alternate setbacks and reduced building height requirements for flag lots.
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b. The residential compatibility (infill) standards of Section 4.0138(B) will apply to all lots except Lots 8, 9, and 10 since most lots are substandard with respect to LDR-7 minimum lot size and/or minimum street frontage. Compliance with Residential Floor Area Ratio (FAR) and supplemental building height setback will be required for those non-standard infill lots at building permit review. c. Per GCDC Section 5.0220(D), safe neighborhood standards will not apply to Lots 4 through 11 because they are located entirely within the Hillside environmental overlay. Only Lots 1, 2, 3, 12, 13, and 14 will be subject to safe neighborhood standards. d. Any flag lots with shared property lines with properties not party to this subdivision shall provide the 5-foot vegetated buffer as required by Section 9.0110(H). e. Construction management plans submitted with building permits in the vicinity of Trees #12, #13, #17, #18, and #19 must comply with the tree protection measures of Article 9.1000. If work is to occur within the tree protection area, an arborist evaluation of tree protection measures and/or supervision may be required. Home footprints must be located no closer than 10 feet from the trunk of these trees. These trees are slated for preservation and may not be removed by exemption request. If removal is requested, a Type I or Type II tree removal permit will be required depending on the reason for removal. 25. Each new home shall have a private pressure reducing valve (PRV) installed behind the meter. 26. Fire Code Conditions. a. Residential homes up to 3,600 square feet require a minimum of 1,000 gpm fire flow. Residential homes from 3,601 - 4,800 square feet require 1,750 gpm fire flow. The fire flow increases from there. Fire Flow forms will be required to be filled out during the permit process. OFC App B b. Each building is required to be sprinklered if the code's minimum water flow is not available. OFC App B c. Put a note on the plans stating “All watermains and hydrants shall operate prior to construction materials arriving on site.” A hydrant must be within 600 feet of the furthest point on each house. OFC 1412.1 & 507 TO BE MET PRIOR TO CONSTRUCTION ACTIVITIES 27. HCA and Tree Protection Fencing. Install the required HCA and tree protection fencing in accordance with the approved grading and/or construction management plan. The contractor shall be notified at the pre-construction meeting of the HCA requirements and instructed to prevent any work/disturbance beyond the HCA protection fence. The construction barrier fencing shall be as per the chain link fence detail, or another sturdy material as approved by the Manager. Orange construction fencing will not be permitted.
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VI. RECOMMENDATIONS A. Invasive Removal. The applicant is encouraged to voluntarily remove invasive vegetation present in the immediate 10-foot perimeter of the proposed building pads. B. Rear Lot Lines Lots 5 through 10. Refine the rear yard boundaries to be simpler, reducing both the number of corners and the number of bearings. It is not necessary to match the mapped HCA boundary line trajectory exactly. Any refinement shall conform with the following parameter. i.
Maintain a total HCA dedication area of at least 19,600 square feet (i.e. 80 percent of the 24,492 square feet of HCA area on the site).
The proposed polyline consists of seven points. A polyline of five points appears achievable. End of Staff Report All exhibits and plans referenced in this Staff Report are filed and maintained with the City of Gresham Urban Design & Planning office and are available for review upon request.
SD/TR/MIS 17-26000019 – Robbins Terrace Subdivision
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