The Central Platte NRD is comprised of 27 municipalities with varying flood control issues and challenges. There has been a multitude of flood control projects across the NRD ranging from dams to levees, to the clearing of creeks and streams. CPNRD works with landowners and other agencies to minimize damages that cause flooding. Our goal is to use each acre within its capability and to treat each acre according to its needs as set forth in the technical guidelines adopted by the District.
Upper Prairie/Silver/Moores Flood Control Project
FEDERAL EMERGENCY MANAGEMENT AGENCY APPROVES CONDITIONAL LETTER OF MAP REVISION FOR THE UPPER PRAIRIE/SILVER/MOORES CREEK FLOOD RISK REDUCTION PROJECT
Grand Island, Neb. (Aug. 23, 2018) – The floodplain maps for northwest Grand Island and portions of Hall County are one step closer to being revised to reflect the recent flood risk reduction efforts of the Central Platte NRD, City of Grand Island, and Hall County.
This significant milestone of the Upper Prairie/Silver/Moores Creek Flood Risk Reduction Project is a result of the Federal Emergency Management Agency’s (FEMA) recent approval of a Conditional Letter of Map Revision (CLOMR). In other words, FEMA indicated that the project, if completed as proposed, will meet the standards necessary to revise the FEMA floodplain maps for the area through a future Letter of Map Revision (LOMR).
The CLOMR is essential to the floodplain map revision process as it provides assurance that FEMA will accept the technical information necessary to update the floodplain maps when the LOMR is submitted. It is anticipated that the LOMR request will be submitted to FEMA as soon as possible after all project components have been constructed.
Despite this news, it is important to note that the area’s floodplain maps have not yet been revised. The effective floodplain maps, which can be accessed through FEMA’s Flood Map Service Center (www.msc.fema.gov), remain the effective floodplain maps until FEMA approves the future LOMR and subsequently updates the maps. As such, those with property in the floodplain should maintain flood insurance coverage in accordance with applicable laws.
The Central Platte NRD (CPNRD), City of Grand Island, Hall County, and Merrick County have been working together in coordination with Nebraska DNR (NeDNR) since 2005 to implement the Upper Prairie/Silver/Moores Creek Flood Control Project. The purpose of this project is to provide flood risk reduction to properties in northwest Grand Island and portions of Hall County. The project consists of construction of four dry dams, an approximately 554-acre detention cell, and a levee. More information about individual improvement projects can be found at www.cpnrd.org/flood-control. For more information, please contact:
- Floodplain Management – Chad Nabity, Grand Island/Hall County Regional Planning Director
- firstname.lastname@example.org, 308-385-5240
- Project Construction – Jesse Mintken, CPNRD Assistant Manager
- email@example.com, 308-385-6282
June 28, 2018 – Van Kirk Bros. Contracting of Sutton, Nebraska, was selected to build the levee for the Upper Prairie/Silver/Moores Flood Control Project in northwest Grand Island in the amount of $572,170.19. Van Kirk submitted the low bid of three. Construction will include a reinforced concrete box culvert, earthen embankment, site grading, storm drainage piping, surfacing, seeding and any other work necessary to provide a complete working system. Work will begin September 1, 2018, and is scheduled to be completed by November 20, 2018.
June 1, 2017- The CPNRD board awarded the Phase II construction bid for the Upper Prairie/Silver/Moores Creek Flood Control Detention Cell Project in Hall County to Hooker Brothers Construction Company of Grand Island in the amount of $2,246,959.00. Nine bids were received to excavate 1,036,300 million cubic yards of dirt for the detention cell. Hooker Brothers had the low bid, which was $1,175,041 below the engineer’s estimate. Construction will begin in mid-July and be completed by May 1, 2018. A bid letting will be held this fall for construction of the levy to be located on Engleman Road.
CPNRD contracted with Van Kirk Brothers Construction of Sutton, Nebraska, to complete the next phase of implementation for the Upper Prairie/Silver/Moores Flood Control Project. Detention cells located approximately five miles west of Grand Island at the Cornhusker Army Ammunition Plant are just one component of the flood control project.
The detention cells (SCLL4-S Phase I and SCLL4N-E Addition) are currently under construction to expand the overall footprint will be 540 acres. Van Kirk Brothers Construction of Sutton, Nebraska, began construction in mid-January with excellent progress given the moderate winter. The Project’s detention cells, located approximately five miles west of Grand Island at the Cornhusker Army Ammunition Plant, are currently under construction. The overall footprint will be 540 acres.
Equipment for this major construction includes four scrapers that hold 20 cubic yards, two excavators, four dump trucks that hold 30 cubic yards, a bulldozer and a road grader. Soil excavated from both cells will be spoiled on site.
Mintken said the north detention cell, located on Airport Road, (SCLL4N-E Addition) is nearly completed. An additional 71,500 cubic yards have been excavated to form this cell. The southern portion of Phase I (SCLL4-S Phase I) included approximately 815,000 cubic yards; located at Capital and Schauppsville roads. Periodic seeding and mulching will take place to ensure that permit requirements are met and that proper erosion control measures are implemented. Phase II was completed in 2017. A levee system located at the northwest corner of Grand Island. The bid letting on that portion of the flood control project will take place in mid-spring.
Much of the area of the Central Platte NRD has long been plagued by floods. On the average, there’s a flood every year in some area of the District, with major floods occurring every six to eight years. The land area within the District is unusual in the fact that most of the tributaries of the Platte River run almost parallel to the Platte itself. Consequently, the tributaries span many miles of the flat terrace or bottomlands adjacent to the Platte before emptying into the river.
In the central and western ends of the District, most of the tributaries originate in the uplands where flood control structure sites are plentiful, but then drop off into the flat terrace or bottomlands and meander for many miles before reaching the Platte River. Many of the District’s other streams, such as Silver Creek, Warm Slough, and the North Branch, originate in the flat terraces or bottomlands where there are no sites for flood control structures. Even Prairie Creek has no flood control structure sites except in its extreme upper reaches.
The Wood River has approximately 173 miles of channel meandering through the fertile Platte River Valley. There are numerous flood control structure sites in its upper reaches. However, in the flood of June 1967 on the Wood River, most of the rain contributing to the flooding in the Grand Island area fell east of Kearney where there are few flood control structures sites. Although flood control structures are or could be, of great benefit to this area, total protection cannot be achieved without some form of channel rectification. The Board has adopted, as a general policy, the design and construction of flood control measures on a watershed basis.
The NRD has developed over 30 flood control structures. The plans for these structures have been designed to provide for orderly development of flood control and other related resources activities in watersheds, with each watershed plan encompassing a number of individual project plans in the total watershed development.
For more information on CPNRD’s flood control projects, contact Jesse Mintken.
More Flood Control Projects
- Snagging and Clearing Projects In December 2015, the board voted to discontinue the snagging and clearing program with the exception of projects already in progress including the Kearney Whitewater Association; who had requested $2,200 to aid in removing trees that have fallen into Turkey Creek along the Whitewater Trail. The trail is available for use by canoes, kayaks, rafts, and paddleboards.
- Warm Slough/Trouble Creek Flood Control Project Due to a history of flood damage to agricultural and urban property within Central City, a project was proposed for reducing flooding along those streams; caused by storm runoff into the Warm Slough, Dry Run, and Trouble creeks. That project would have included construction near Grand Island in order to take care of storm runoff from the city, as well as channel clearing and renovation from Grand Island to Central City. A study determined that portions of the project were not economically feasible. A revision was made that subsequently dropped the infeasible portions of the plans. Partial funding was provided by the state through the Nebraska Natural Resources Development Fund. Cosponsors, with varying shares of the local matching portion, were CPNRD, Merrick and Hall counties, and cities of Grand Island and Central City. Construction was completed in 1993 and maintenance responsibilities were turned over to Merrick County and Central City. In 2002, the NRD performed snagging and clearing of the Lower Warm Slough from Grand Island to Central City with an initial cost of $110,000. Additional funds in the amount of $23,000 were transferred to complete the project since the construction company was required to truck the dirt away due to the close proximity of wetlands in the area. From June 1-8, 2008, Central City received over 6” of rainfall, which exceeded a 100-year event. The project has improved drainage of the entire watershed.
- Prairie-Silver Flood Control Project A flooding problem was studied by the NRD in central Hall County, just west of the city of Grand Island. CPNRD determined that the problem was caused by two short stretches of Prairie Creek and Silver Creek that produced channel overflow after large storm events. A project was developed to correct the problem by cleaning out the channels and constructing training levees to prevent the Construction was completed on the project in 1986. Construction and land leveling in the area disturbed natural drainage flows along the Prairie/Silver Creek, northwest of Grand Island. In 2000, a design proposed by the NRCS was approved by the board to install a uniform drain and add culverts for a two-mile stretch. The total cost was $22,000 of which the NRD provided $17,500.
- Clear Creek Watershed Clear Creek watershed, located in Polk County, encompasses 75,700 acres. It has a long history of flooding. A feasibility report for flood prevention and watershed protection was developed and completed in 1978 which lead to the construction of 15 flood control structures completed in Clear Creek Watershed over the last several years. Funds from the Natural Resources Development Fund were received on five of the larger structures. Polk County provided funds to construct additional smaller structures including road structures
- Lepin Ditch Flood Control Project Landowners petitioned CPNRD in 1993 to solve excess storm runoff that was overloading the “old north channel” of the Platte River, north of I-80 in southwest Hall County. A study by Nebraska Department of Roads (NDOR) & CPNRD determined that the problem resulted when I-80 was constructed and an attempt was made to redirect runoff from the Lepin Ditch to another crossing site under the Interstate. A joint project was developed to place a culvert in the vicinity of the natural channel to allow runoff to flow under the Interstate at $700,000 with partners CPNRD, NDOR and Hall County. Easements were obtained from area land-owners for construction and maintenance of the ditch. The county provided site preparation and ditch excavation and provides maintenance. CPNRD contributed $120,000; which was completed in 1995. NDOR provided funds for the culvert.
- Cairo Downtown Improvement Project In 2007, the NRD approved $50,000 in flood control funds to aid in the construction of adding a 48” drainage outlet for the Project to divert excess water along the Hwy 11 corridor. The previous drainage system couldn’t handle a one-year rainfall event, which caused overflow ponds and flooding in low areas. The community of Cairo contributed $2 million to the project.
- City of Gibbon The City of Gibbon filed a formal request for help with a drainage project. Olsson Associates proposed solutions to the city’s current drainage system including relocating the existing sluice gate, improvements on hydraulic conditions at the outfall and installing an automated sluice gate system. The total cost of the project is estimated at $150,000 and has been added to the Hazardous Mitigation Plan to be considered for Federal funding in the future. In 2008, provided $50,000 to the City for improvements to the stormwater system and the project was completed in 2010. In April 2015, OA reviewed what the City of Gibbon had accomplished towards drainage issues and the additional needs in order to resolve remaining issues. CPNRD staff has facilitated meetings with the City of Gibbon, Buffalo County, and CPNRD to address the remaining drainage problems.
- Odessa Area Flood Control Project Miller & Associates of Kearney started the final design of the Odessa Area FCP in 2008 and completed it in 2010 at a cost of $15,000. The Project is located east and south of the project boundaries include the Odessa Road to the west, 24th Road to the North, and Sartoria Road to the east. The two-mile project consists of improvements to existing roadside and field drainage ditches, replacement of culverts and supplementing existing culverts.
- Doniphan Drainage In 2015, the Village of Doniphan requested $4,000 to pump standing water from a detention cell located in the city park and into the curb and gutter system. The project was completed in the fall of 2015.
- Clarks Floodplain Silver Creek is the major source of flooding in the area. The board approved participation in the Clarks Floodplain mapping study up to $5,000; which is 50% of the expected cost of the study and needed to meet FEMA requirements. The study and funding were added to the 2014 Fiscal Budget.
- Lake Helen In 2013 and 2014, CPNRD provided $75,000 towards the restoration of Lake Helen in Gothenburg for water quality conditions. The lake was drained to accommodate: excavation of 171,773 cubic yards of sediment, stabilization of 3,391 linear feet of shoreline, development of underwater shoals, installation of a circulation system, dam repair, installation of a pier and boat ramp. Sediment and nutrient loading from outside the lake boundary was addressed by treating the lake with aluminum sulfate to precipitate phosphorus, installing a deeper well to access lower phosphorus water, and stocking recreational fish. The total cost of the water quality and habitat project was nearly $1.8 million. The project was completed in May 2016.PROJECTS UNDER MAINTENANCE
- Kearney Northeast Flood Control Project A cooperative effort involving the City of Kearney, Buffalo County, and CPNRD, was initiated in 1990 due to the expansion to the northeast of the city of Kearney. The expansion has resulted in increased flooding on an unnamed tributary of the Wood River resulting mainly from storm runoff. CPNRD obtained aerial photography and participated in survey work needed for topographic mapping of the affected area. After the mapping was completed in 1991, NRCS conducted a feasibility study to determine what options were available. In 1995, Miller & Associates developed a plan for the watershed; including channel improvements, drop structures, road crossings and a detention cell. Cosponsors shared costs of the project & agreed to do the construction in phases so taxpayers would not have a large one-time impact. To stop a serious erosion problem at the point where water had been entering the Wood River, a drop structure was constructed in 1996 at the cost of $240,000 by the NRD. As part of it’s bridge replacement program, the County also built a road structure used by the project.The project was completed in three phases: Phase I: The existing channel was widened starting at the drop structure and meandered westerly and south to a point near 56th Street on Eaton Road. Phase III: (Completed before Phase II) In 2000, properties were bought and construction was completed on the detention cells and channel improvements. Detention cells are located 1/2 mile north of “N” Ave and 56th St in Kearney. Construction included 300,000 yards of excavation with a 50 ac/ft storage design for a 100-year storm and a 50 ac/ft storage design for a 25-year storm on the other cell. In 2003, the NRD approved a contract change to complete channel improvements south of the detention cells and to control erosion. There were 800,000 cubic yards of soil excavated to create the channel. Storage capacity is 200-300 ac/ft. Phase II: Consisted primarily of channel improvements from the Phase I channel south to about 39th Street and then westward to Antelope Road. Phase II to Phase III, from 56th Street to Avenue N was completed in the spring of 2006. Total cost of the project was $3.4 million.
- Kearney West Clearing Project In the fall of 1999, landowners west of Kearney requested a clearing project to assist them with flooding problems along Turkey Creek, also known as the Platte River North Channel. About 2 1/2 miles were cleared after the request. In 2000, an additional mile was cleared and snagged. Snagging & clearing was done in 2000 on the North channel and again in 2001 at a cost of $8,650. In 2002, the NRD was notified that the North Channel of the Platte River/Turkey Creek had eroded to within 5 feet of a local sandpit. The U.S. Corps of Engineers surveyed the problem and provided an Emergency 404 permit to the NRD to stabilize the bank. The City of Kearney provided 25% of the total cost (approximately $1,850) and the NRD provided $13,500.
- Dry Creek Clearing Project Debris from a wind storm/tornado fell into the Dry Creek channel northeast of Cairo in 1997, prompting a request from landowners for a clearing project. The NRD Board authorized a clearing project. The cost of the project completed in the winter of 1998 was approximately $11,500. Area landowners petitioned the NRD to complete about 21,000 feet of additional clearing; which was completed in the winter of 1999-2000 at a cost of about $42,000. In 2012, a three-mile channel improvement was completed to the west of Central Nebraska Airport and a culvert was added under Gunbarrel Road. Maintenance is completed by the NRD as needed.
- Amick Acres Project The Amick Acres Project Improvement Area is located in south central Hall County, just to the west of Doniphan. It diverts flood and drainage water away from the Amick Acres residential subdivision by utilizing part of a county road ditch for approximately one mile of channel. The initial cost of the project was $25,000; most of which was assessed to the benefiting landowners. Maintenance is performed as necessary at a estimated cost of $500-$1,000 annually. Actual costs are calculated and assessed to benefiting landowners.
- Platte County Project The Platte County Project is an improvement area located just southwest of Duncan. The project provides drainage improvement and minor flood control benefits to 1,300 acres of irrigated cropland in southwest Platte County. Maintenance is performed as necessary at an estimated cost of $500-$1,000 annually. Actual costs are calculated and assessed to benefiting landowners.
- Wood River Watershed In 1972, snagging and clearing was completed from the mouth of the stream to Gibbon in 1972. In 2002, one mile was cleared at a cost of $20,000. Annual maintenance for the Wood River Clearing Project is about $10,000. Additional spot clearing is completed as needed.
- Moores Creek Flood Control Project In the 1980s, CPNRD, and others recognized the need for flood control in Hall & Merrick counties on Moores Creek. Project sponsors- CPNRD, City of Grand Island, Merrick & Hall counties– submitted the feasibility study to the Nebraska Natural Resources Commission in January 1984. The Commission approved the Moores Creek Project and agreed to cost share at a 65% rate. A three-phase construction plan was developed and carried out. Phase I: Channel improvements from the mouth near Archer upstream to the Hall-Merrick county line were completed in 1990. Phase II: Three detention/retention and wildlife habitat enhancement cells were completed on Moores Creek channel from the Hall-Merrick county line upstream to Grand Island. Phase III: Waterways and bridges were constructed to enable storm runoff from the Capital Heights area, northwest of Grand Island, to drain into the improved Moores Creek channel. Project was completed in 1995. Annual maintenance is completed as needed with an approximate cost of $20,000.The U.S. Army Corps of Engineers participated in studies in the early stages of the Project. Following new rules for such projects adopted in the 1980s, the Corps reviewed its findings and conducted reconnaissance studies to determine if a project was possible after the criteria changed. The review indicated highly feasible floodway projects using several different routes. Following public hearings in 1989, the Corps narrowed the choices and began a study to determine the actual feasibility of a route to carry excess water from the Wood River and Warm Slough into the Platte River. Appropriation and construction-start authorizations were obtained from Congress in 1996. The Corps’ revision of plans and increased projected cost required new Congressional re-authorization, accomplished in 1999. Construction began in March of 2000. In 2002, the Corps contract was increased by $1 million due to miscalculations regarding the amount of topsoil needed for the project. 180,000 yards of soil was added with co-sponsors paying $95,000 of the increase. A total of 500 acres were involved in land acquisition for the project; 2 miles west of Hwy 281 to the Hwy 34 bridge along the Platte River where five bridges were constructed. A reappraisal of Hall County Park resulted in an agreement/compensation for damages to the RV park with the Hall County Board. The board proceeded with the remaining 11 tracks of land needed for the project.Benefits of the project include flood control for flood zones in the Grand Island, rural Hall and Merrick counties and groundwater quality improvement. Close to 7,000 acres of land were taken out of the flood zones. FEMA revised its floodplain maps in 2004, taking away the need for flood insurance in southern Grand Island. Landowners had been paying $317,000 to protect $56 million worth of property prior to the revision of the floodplain maps. Full funding of the Federal share enabled construction to be completed on schedule. CPNRD borrowed funds in the amount of $1.1 million at an interest rate of 6.5%, to meet the needs of project construction over a 2-3 year period. All monies were reimbursed to CPNRD by the State of Nebraska through a cost-share grant and the other local sponsors. The entire project was completed and dedicated in May 2004. Total cost was about $15 million as follows: $7,148,000- U.S. Army Corps of Engineers, $4.million– Nebraska Department of Natural Resources, $1.4 million- CPNRD, $1.2 million-City of Grand Island, $352,000- Hall County, $200,000-Merrick County. CPNRD is responsible for maintenance, with costs split between the cosponsors. In May 2015, the board approved $25,000 for JEO to complete design work for the Wood River Flood Control Project’s System-Wide Improvement Framework. The board also approved $20,000 for maintenance and repairs required by the Corps of Engineers.
- Wood River Flood Control Project The Wood River has approximately 173 miles of channel meandering through the fertile Platte River Valley. There are numerous flood control structure sites in its upper reaches. During the flood of June 1967 on the Wood River, most of the rain contributing to the flooding in the Grand Island area fell east of Kearney where there were few flood control structures sites. Ten inches of rain fell over nine days from June 7-15, with the most falling on June 13 at 3.2”. After the extensive damage in Grand Island caused by the Wood River and Warm Slough in 1967, the area is now protected by the Wood River Flood Control Project. After 30 years of planning, the Wood River Flood Control Project was put to the test on May 11, 2005, and recognized as an event that exemplified the importance of flood control projects within the District. The 300 foot-wide channel of the diversion project provided flood control protection for over 1,500 homes and businesses. A total of 7.21” of rain fell between May 11th -May 12th, more than any one-day of rainfall during the 1967 Flood. The project was put to the test again in June 2008, when the area received 6” of rain from June 1-8.
- Prairie Creek Clearing Project Flooding from Prairie Creek caused considerable damage to agricultural property in the past. While the Prairie-Silver Creek Flood Control Project had a local effect, it didn’t solve all of the flooding problems on Prairie Creek, nor did it evolve that a feasible project could be developed to solve all of the flooding problems on the stream. Further study indicated that damages could be reduced by keeping the channel clear. Snagging and clearing projects involving the selective removal of timber, trash and debris from the stream channel in an area of 35 feet on either side of the center of the channel were completed from the mouth of Prairie Creek in Merrick County to the Hall-Buffalo county line. Annual maintenance is approximately $10,500.
- Buffalo Creek Watershed-Structures Feasibility planning for flood control was completed in the Buffalo Creek Watershed, located in Custer, Dawson and Buffalo counties. CPNRD received approval for cost-share funding from the Natural Resources Development Fund to construct seven flood control structures in the watershed: B-1, B-3, C-5, F-l, F-3, F-5 and F-7. Additional work: B-1: the largest structure, was completed in 1983 along with the supply canal, 1.6 miles of power line relocation and 1/2 mile of county road improvement. In addition to flood control, the project was expanded to include recreation and groundwater recharge. Cracks were identified in the B-1 structure in the fall of 1983. Repair included installing a chimney drain system on the back side of the structure and was completed in 1985. In 1987, the reservoir was opened for day fishing. In 1995, a petition from numerous landowners requested that the NRD discontinue filling the reservoir because they were concerned that the reservoir contributed to high water tables in the c Hydrological studies conducted by the NRD showed that the B-1 reservoir made no significant contribution to the high water tables and that projected groundwater declines had not materialized due to continued strong annual rainfall amounts. However, the request to stop filling the reservoir was granted effective January 1, 1996. In May 2009, the board voted to start filling the B-1 Reservoir in Lexington every other year starting in spring of 2010 and was required to fill the reservoir once every five years to keep the NRD’s water right. In March 2011, the board approved leasing water from B-1, for a one-year basis, to 40-45 individuals who needed 1-15 AF of water. In March 2013, the board voted to start filling the reservoir every year and to get it back to its original concept. The NRD has a diversion right of 4,000 acre/feet of water per year from NPPD to fill the reservoir and there are plans to have the NGPC begin stocking the reservoir within this planning period. F-7: Cracks were identified in the structure and repair was completed in 1990 at a cost of $11,500. Two sites in the Buffalo Creek Watershed north of Lexington were studied to determine their potential as flood control structures. Based on the study, the NRD board determined that construction of flood control structures at those sites was not feasible and that all further planning efforts for the watershed would be discontinued. Operation & maintenance continues for all of the structures in the watershed including dam safety checks. In addition, CPNRD will fill the reservoir periodically with the minimum amount of water to satisfy the project’s Platte River water right.
- Silver Creek Watershed Located in Merrick County, this watershed encompasses approximately 90,000 acres. A feasibility study was completed in 1979 to provide flood relief in the watershed with the project completed in four parts that consisted of mainly channel improvement. Phase 1A: Lower 4.1 miles of Silver Creek. 1B: One mile of Silver Creek and 15 miles of the Clarks drain. Phase 2: Continued upstream on Silver Creek for 6 miles. Phase 3: The next 10 miles upstream. Phase 4: Wasn’t completed until the fall of 1987 due to wet weather in the 1985/1986 construction seasons. The 11-mile stretch upstream from Hwy 14 north of Central City to Silver Creek’s headwaters west of Chapman. The Board approved extension of the project at a cost of $7,500 in February 2000 due to additional flooding. Maintenance costs are approximately $20,000 annually.
- County Road Structures The NRD’s road structure program helps counties provide minor flood control by replacing bridges on their roads with structures that generally consist of an earthen embankment with a culvert or tube at the bottom. Storm water is stored in small reservoirs to prevent damage to agriculture land below the road structure. CPNRD has completed several structures in cooperation with the county highway departments and is conducted on a request basis. CPNRD will continue maintenance on these county road structures.
- Kirkpatrick Memorial Park Lake In October 2016, the board approved a $25,000 request from JEO towards lake improvements for the Kirkpatrick Memorial Park Lake in Lexington, NE. Improvements include 4,000 cubic yards of dredging, 2,500’ of bank improvements including removal of trees, and a 700’ sea wall to the four-acre lake. The project will provide improvements to water quality, aquatic habitat, public access and provide an area for educational events. Construction is expected to be completed in the fall of 2017.PROJECTS UNDER CONSTRUCTION/PLANNING
- Upper Prairie/Silver/Moores Flood Control Project The NRD and the City of Grand Island completed a detailed analysis of the hydrology and 100-year floodplain in the upper parts of the Dry, Prairie, Silver, and Moores Creek watershed located south of Hwy 2 and east of Hwy 281. To accomplish flood control, upland and lowland flood control structures were developed, including roadways to act as dams, berms built to keep the creeks within their banks, and water detention cells were built on 500 acres at the former Cornhusker Army Ammunition Plant. Because of the widespread improvements to croplands and expanding development of urban property in the study area, an application and feasibility study report were filed with the Nebraska Natural Resources Commission for cost sharing for a 10-year, $15.5 million construction project. The project was approved and received $8.3 million in state funding, with the remaining $7.2 million to be financed by co-sponsors. The completed project will include:
- 3 P.L.566-type floodwater retarding sites in upland areas of the Prairie Creek watershed southwest of Cairo
- one upland detention site in the Dry Creek watershed
- a series of small excavated floodwater detention sites in lowland areas along upper Prairie Creek
- 3 excavated off-channel detention sites in the Silver Creek Watershed
- one low-level berm to prevent basin overflows from Silver Creek into Moores Creek
- Other parts of the Prairie Creek channel are slated for clearing to improve their capacity
Construction was phased over a 10-year period, starting with the construction of the off-channel lowland sites in Silver Creek and stepping through the rest of the facilities depending on their contribution to flood control. The study showed that a 100-year flood would inundate 23,000 acres of lands south of Hwy 2, producing crop damages of $3 million a 10-year flood would cause $1.6 million in crop damages. In addition, the flood waters would collect along Hwy 2 resulting in large quantities of water flowing east into developed areas of northwest and west Grand Island. The results of the study proved true on May 11, 2005, when central Nebraska was hit with a flood. The city of Grand Island sustained an estimated $3-5 million in damages and Hall County sustained a total of $12-15 million. There were 2,769 homes and businesses damaged in the area that would’ve received flood relief from the project. Acquisition of or easements included 1,800 acres (mostly dryland crops or pasture), excavation of 3,500 AF of off-channel storage in lowland areas, construction of 6 upland floodwater detention dams and outlet works and installation or replacement of a few roadway culverts under Hwy 2 and other county roads. 500 acres of irrigated cropland was acquired for the flood detention cells at strategic locations. The design phase began in 2005, construction began in 2006. In 2011, directors approved a revised agreement with Hall County on the White Cloud Road dam. As part of the agreement, CPNRD set up a maintenance fund for up to $10,000 for 10 years for erosion, gravel, etc. In 2015, an amendment contract was approved in the amount of $118,650 to allow JEO to submit a Conditional Letter of Map Revision (CLOMR) to FEMA that provides an early-stage assessment of the flood risk reductions due to proposed flood control measures. When completed, the project will protect northwestern Grand Island from Prairie and Silver Creek flooding; reduce future flood damages to crops, properties/infrastructures; and eliminate an
estimated $130 million in damages during a 100-year (1% annual chance) event. In October 2016, the board condemned 7.25 acres of irrigated land located at Engleman and Airport roads following unsuccessful negotiation attempts. The property is central to the existing levy and to a new levy.
As of August 2017, all four upstream flood control dams and detention cells are completed. Phase I, north detention cell, located on Airport Road, (SCLL4N-E Addition) was completed in summer 2016. Equipment included four scrapers that held 20 cubic yards, two excavators, 4 dump trucks that held 30 cubic yards, a bulldozer and a road grader. Soil excavated from both cells was spoiled on site. An additional 71,500 cubic yards was been excavated to form the north cell. The southern portion of Phase I (SCLL4-S Phase I) included approximately 815,000 cubic yards. It is located at Capital and Schauppsville. Periodic seeding and mulching will take place to ensure that permit requirements are met and that proper erosion control measures are implemented. Phase II construction bid for the detention cell project was awarded to Hooker Brothers Construction Co. of Grand Island in the amount of $2,246,959.00; which was $1,175,041 below the engineer’s estimate. Nine bids were received to excavate 1,036,300 million cubic yards of dirt for the detention cell. Construction began July 2017 and is scheduled for completion by May 1, 2018. A bid letting will be held this fall for construction of the levy to be located on Engleman Road. The entire project is scheduled to be completed in 2018.
2. Hazardous Mitigation Plan In September 2008, the NRD was awarded a FEMA grant to develop the multi-jurisdictional All-Hazard Mitigation Plan; which enables communities to take action and reduce threats from natural disasters. Public input from officials and landowners were a key component of the hazard mitigation planning process. Regional meetings were held to obtain input on the hazard mitigation plan in the initial stages. Potential hazards affecting the area and individual communities were identified, critical facilities located, and potential mitigation actions or projects were listed. Among the many projects being considered to protect people and property are flood and drainage system improvements, purchasing backup generators for critical facilities, evaluating/replacing alert sirens, purchasing weather radios, constructing public tornado shelters/safe rooms, tree inventory and maintenance programs to reduce electrical outages. Kirkham Michael Engineering of Lincoln, Nebraska, assisted in the development of the plan; which became active in July 2012. In 2015, the board hired JEO Consulting to update the Plan in the amount of $120,000 (must be updated every four years.) In order to be eligible for emergency funds, each county, community, and school are required to actively participate in the process. In September 2017, the board of directors will consider adopting an update of the CPNRD Hazard Mitigation Plan. CPNRD sponsored the initial development of the plan in 2010 and is again sponsoring the update of the 2016 plan. Jurisdictions which participate in the planning process and adopt the plan locally become eligible to apply for FEMA grants aimed at implementing mitigation projects to reduce future losses from natural hazards. JEO Consulting Group’s Hazard Mitigation & Emergency Planning team assisted in the plan update. Local cities, towns, villages, schools, and fire departments that participated in the initial Plan were required to participate in the FEMA plan review process to be eligible for the FEMA grants.
3. Ice Jams In July 2011, the board approved an inter-jurisdictional cooperative agreement on how to deal with ice jams in the Middle Platte River, with the formation of a continual escrow (interest-bearing) account in the amount of $50,000. If an ice jam were to begin, CPNRD would be the first entity to start the process of calling FEMA & NEMA; in which the entire process could be completed in one day. The agreement is signed by seven partners who have deposited $37,000 in an emergency fund to use in the case of an ice jam on the Platte River. In 2016, the board voted to dissolve the existing Platte River Ice Jam Removal Agreement. Instead, the agreement partners plan to develop a working agreement that will focus on emergency preparedness in the event of an ice jam related to flooding and safety education. All funds in the ice jam account were returned to the partners who include: Tri-Basin NRD and Buffalo, Hamilton, Merrick, Phelps, and Kearney counties.
4. Elm Creek/Turkey Creek Watershed A feasibility study was conducted for $125,000 and submitted to the Nebraska Resources Development Fund to request cost share. A community meeting was held in June 2006, on the feasibility study for Elm Creek Watershed Flood Control Project. 130 landowners attended. Olsson Associates’ Plan consisted of a 975-acre flood control and re-regulating reservoir located northwest of the Village of Elm Creek and two dry flood control structures located on Turkey Creek. The reservoir would provide both traditional flood reduction benefits to the Village of Elm Creek and non-traditional environmental benefits including recreation. The Turkey Creek structures would reduce current peak flows to downstream areas. Together, the flood control structures would provide flood protection to the Village of Elm Creek and downstream cropland. The preliminary cost estimate was $22.8 million. The board approved a study with OA to perform a geotechnical investigation/seepage analysis of the area. The study involved the drilling 30 test borings at the reservoir site and adjacent lands to determine if leaching would raise adjacent water tables to a level that would create problems for either cropland or basements. OA developed a preliminary design feasibility study and CPNRD applied for Resources Development Funds. In June 2012, the board again reviewed the project due to a potential new source of funding from the Nebraska Water Cash Fund. The board authorized staff to work with OA, Nebraska Public Power District (NPPD), State of Nebraska & Platte River Program on options to move forward with a project. The proposed project was estimated at 6,800 -12,000 AF depending upon future agreements with a projected cost of at least $35 million. In 2013, the board approved the transfer of funds in the amount of $631,465 that was originally designated for the proposed Elm Creek Re-Regulating Reservoir to the CNPPID’s new J-2 Reregulating Reservoir project; cutting the Elm Creek project from the budget.
5. LiDAR A LiDAR agreement was approved in July 2012 to provide district-wide coverage of topographic elevation developed from aerial radar detection. The NRD’s cost will be $40,000 for Custer County, providing necessary data for several projects and programs. Data is scheduled to be collected from November 2012 to March 2013, with results available for use in August 2013. Other NRDs and partners included: Lower Platte North, Twin Platte, Lower Loup, North Platte, and Middle Niobrara NRDs; Nebraska Department of Natural Resources; Nebraska Department of Environmental Quality; and the Nebraska Natural Resources Conservation Service.6. GI Dewatering Study The NRD began participating in the Grand Island Dewatering System Study in September 2000. The Study identified a practical groundwater dewatering system to remove groundwater from residential basements and minimize impacts on the project area. The study also assessed potential transmission and discharge location options, financing options, potential impacts on water quality and quantity, and subsidence issues; using both low and high capacity vertical wells. The NRD delivered public opinion surveys to the northwest and southeast project areas prior to the initiation of the Study, with the majority of responses returned as “very interested” in the Study. The Study areas fall within the “Valleys” topographic region, characterized by low relief along streams that are underlain by alluvial clay, silt, san, and gravel. The general direction of groundwater flow is east to northeast generally paralleling the Platte River.
Evapotranspiration (ET) losses are relatively high due to a shallow water table; saturated thickness of Quaternary deposits in/around Grand Island ranges between 80-200’. Depth to water table ranges from 5-20’ below ground level. In 2012, Olsson Associates presented information to the board about the draft 2012 Study to improve and expand project implemented in 1998. The original study involved 29 dewatering wells compared to 33 in the 2012 updated study. Three dewatering areas and areas of contamination were taken into account with wells proposed to be outside of those plumes. Prior reported that the Grand Island City Council was receptive to the proposed updates and that the Council would like the NRD to be involved in the project. There has been no further contact from the Grand Island City Council.
7. Dams Inventory In October 2016, the board approved a contract with JEO Consulting in the amount of $39,500 to conduct an inventory of dams that are one acre or larger within the District. Staff will request the remaining fee of $25,000 through FEMA’s Hazard Mitigation Fund.
Do you own property along the Platte River? With river flows predicted to be above average this winter, flood potential does exist. Landowners are being cautioned to be prepared for flooding, especially those who have experienced ice jam flooding events in the past.
You may be wondering why the potential for ice jams is higher in some years and not others? Ice jams occur with changing temperatures such as a hard freeze followed by a quick thaw. During the cold winter and early spring months, ice begins to form in the river. When there is enough ice, it will “jam” up the river and create blockages to the water flow. This forces the water out of its banks and creates a flood. Click here for ice jam specifics along the Platte River.