PENINSULA DRAINAGE DISTRICT NO. 2
Peninsula Drainage District #2 is located in Multnomah County, along the left bank of the Columbia River, approximately 5 miles Northeast of the city center of Portland.  It borders on North Portland Harbor opposite Columbia River miles 106.5 to 108.2.  The district is bounded on the north by a levee along North Portland Harbor, on the west by the Denver Avenue fill and on the south and east by a continuous levee along Columbia Slough and Peninsula Drainage Canal.  Peninsula Drainage Canal, which separates Peninsula Drainage District No. 2 from Multnomah county Drainage District No. 1, is plugged at both ends, at its junction with Columbia Slough, and on the Columbia River.  The Union Avenue fill, carrying U.S. Highway 99E, crosses the district in a southwest corner on a viaduct and fill which merges with the Denver Avenue fill about midpoint on the west boundary of the district.

The district includes 1,475 acres, of which 1,326 acres are improved (principally industrial and residential) and 20 acres are sloughs and drainage canals.  The ground elevation varies from 10 to 27 feet NGVD.  Land use is divided among agriculture, recreation, industrial, commercial, and residential.  Developments include several motels and trailer courts, Columbia Edgewater Golf Course, Delta Park, Columbia Elementary school, many businesses with small industrial building, a large number of residences and several large trucking companies.

EXSISTING LEVEES AND PREVIOUS WORK
Construction of the levee system was started in 1921 and since 1939 the Corps of Engineers has participated in several levee improvement and emergency repair projects to maintain and upgrade the District’s flood protection system.  During the 1948 flood, the Denver Ave. embankment was breached and the district flooded.  Following the food, the Denver Ave. fill was reconstructed.  In 1959, in response to serious seepage problems that occurred in the 1956 flooded, a new pump house was constructed, relief walls were installed at the Denver Ave. and Schmeer Road intersection, several sections of levee repaired and reinforced, and the Peninsula Drainage Canal was plugged.  In 1963 several sections of the Oregon Slough Levee were reinforced with a sand blanket placement on the interior slope.  Additional repairs were made on the Oregon Slough Levee in 1966 and 1967.  Also in 1967 at the intersection of the Columbia Slough Levee and Denver Ave. highway embankment was reinforced with a sand blanket on the landward slope.  A short section of revetment was placed on the Oregon slough Levee in 1970.

Significant data on the district and its flood protection system are presented in the following tabulation and the system is shown in plan on Plat 2

CONSTRUCTION
From 1921 until present, improvements and/or repairs were made as follows:

From 1939 – 1940 the Corps approved a project to reconstruct and enlarge the existing levee.  Work involved reinforcing 960 linear feet of concrete wall, raising and reinforcing 3,200 linear feet of levee, installing pipe drains and culverts, constructing a drainage ditch and pump station, and placing stone revetment.

In 1948 to repair and restore the protective system destroyed by the flood.  This work involved repairing a pumping plant, cleaning out drains, sewer outlets, culverts and ditches. Placing a 72” culvert under Union Ave., and replacing the ring levees on Union Ave.

In 1959, relief well and a pumping plant were constructed, repairs of a levee section was completed, and levee toe reinforcement placed.  The Peninsula drainage canal closure No. 1 was also completed this year.

In 1963, a sand blanket was placed on the landward slope of the levee along North Portland Harbor.

In 1966, the Corps repaired and restored the levee at Station PD2 38+00.

In 1967, the Corps repaired and restored a sunken area.  In addition, a sand blanket was placed on the landward slope of the levee at Denver Ave. and Schmeer Road.

In 1970, 230 linear feet of bank protection was placed.
 
In 1979, the district upgraded the levee system to provide protection against the 100-year recurrence frequency flood event, which was determined to be elevation 28.5 ft. NGVD.  The 100-year recurrence frequency flood event elevation at Peninsula drainage District No. 2 is now considered to be 27.5 ft. NGVD as per North Pacific Division draft report “Review of Flood control” dated November 1987. 

TIDEBOX LOCATIONS  None
STOPLOG CLOSURES   None
PUMPING PLANTS
NE Schmear Rd - Station 270+00
No. Of pumps - 2
Capacity  20,000 GPM ea.
Condition  - Excellent, installed 1999
Constructed - 1959, re-constructed in 1999 
NE Fazio Way - Station PD2  194+00
No. of pumps  -  2
Capacity  20,000 GPM ea. combined at 21-foot static head
Condition  -  Excellent, rebuilt in 1998
Constructed  - 1982

GENERAL INFORMATION
The Corps of Engineers and the District completed a major Levee rehab project along NE Schmear Rd. in 1998. Repairing the toe of the Levee with 40,000 tons of riprap.

The levees in the District are in very good condition and has received an excellent Corps of Engineers rating.

PERTINENT DATA
Area Protected - Within boundary 1,475 Acres

LEVEE
Length   5.3 Miles

Top Width (in feet)
Main Levee 12.0  Min.
Denver Ave. Embankment 90.0  Max.

Sideslopes                     Riverward               Landward 

N. Portland Harbor        1:2                        1:2.5 – 1:3 Columbia
Slough                             1:2                        1:2.5 – 1:3.5 
Denver Ave. Emb.          1:1

TOP ELEVATION (in feet NGVD)
Main Levee     U/S end =35.8      D/S end = 35.3

LOCATION OF REVETMENT
Station 41+50  to  43+65

PRELIM. PEAK FLD. EL. (in feet NGVD) at the MIDPOINT of LEVEE

10yr       50yr      100yr       500yr       Levee Design Flood

21.8       25.8       27.5       32.2          32.4

LEVEE FREEBOARD (in feet NVGD)
Levee Design Flood -3.2
100 year Flood   8.0

SAFE WATER LEVEL ( in feet NGVD)
Main Levee    U/S End = 28.5   D/S End = 28.0

*The drainage district improved the levee to provide protection for up to a 100-year recurrence interval flood in 1978 and 1979.  The Portland District Corps of Engineers certified this level of protection.  The 100-year recurrence interval flood elevation at that time was recognized to be 28.5 and 28.0 feet NGVD at the upstream and downstream ends of the district, respectively.   


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