Ozarks Electric Cooperative required the design of 4 miles of 161kV transmission line through a remote location and difficult terrain. Allgeier Martin completed the design of a four-mile 161kV transmission line. Approximately one half of the line is H-Frame construction with steel poles, crossarms and x-braces. The other half is single pole design with steel poles, braced post insulators and distribution under build.

• Assisted with routing
• Obtained right-of-way easements
• Prepared specifications for obtaining terrain information through LiDAR
• Prepared bid documents for clearing
• Staked the line for clearing
• Detailed materials lists were also prepared for procurement

Arkansas Electric Cooperative Corporation needed to clear the right-of-way in preparation to build a new 23-mile 69kV transmission line to connect a 13.2kV Substation to another 13.2kV Substation as part of a larger plan to meet the area’s growing demand. Allgeier Martin provided design services for the clearing and assembled and administered the contract for the clearing. The design included identifying and quantifying areas for clearing, locations and specifications for fencing, gates and culverts, as well as estimated locations and quantities of necessary SWPPP measures.

• Parts of the route were swampy, which caused design and construction challenges
• Access was limited in many areas and there were many ditch crossings that needed to have new culvert crossings
• Contractor used boats in some places to remove trees and other brush

Sho-me needed a 161KV transmission tie of adequate capacity to connect their Macedonia Substation and Ameren's Dillon substation. AMA designed a transmission line utilizing 795 (Drake) ACSR conductor. This line was comprised of a single circuit section on new right of way and a double circuit section (161/69KV) using existing right of way.

• Two design types, a transmission line crossing, modifications to an existing line and connections to two separate substations
• Both designs used steel pole construction with direct embedded tangent structures, guyed dead-end structures and self-supported angle structures on caisson foundations
• AMA also provided technical specifications and bid documents for purchase of the steel poles and for the balance of materials

The new Clear Creek Wind Farm, located North of Maryville in Nodaway County, is comprised of 111 Vestas turbines across approximately 31,000 acres. To accommodate the new wind farm, this required a rebuild of about 30 miles of 161 kV line. Allgeier Martin designed the 161 kV line rebuild and provided land surveying and right-of-way services for the 30 mile-line.

• Wood H-frame supports for 161kV transmission line
• Approximately 30 miles of line with tie-ins at three substations (Gentry, Nodaway, Maryville)
• Final price was 20% less than bid price

Liberty Utilities assigned Allgeier Martin the task of designing the new poles and solving the water rot issue. The distribution poles were replaced with steel poles with a cap that can be removed and another piece of pole bolted on top to add future transmission. The steel poles were placed in concrete foundations to mitigate water rot and increase longevity of the structures.

• Multi-phase design and construction to accommodate budgets

OECC hired AMA to remove and rebuild the low voltage side of the substation, replace station transformers, move the capacitor bank, remove regulators, add Low Voltage (LV) feeder positions for present and future positions, rework connection from High Voltage (HV) bay to station transformer and move sectionalizing switch on HV structure.

• Completed all boundary and topographical site surveying
• Expanded the security fence of approximately 400 linear feet
• Low voltage structure modified and installed with three feeder positions, two future feeder positions, a future regulator bay, fiber building power feed, capacitor bank feed and feed to existing Automatic Meter Reader (AMR). All switches and insulation levels in LV section are 25kV. Mobile transformer connections provided for use during construction and in case of emergency.
• New 795 kcmil 26/7 ACSR installed from HV bay to transformer; dual 1000 kcmil MHD CU, 61-strand installed from transformer to LV structure; 4”x4”x3/8” aluminum angle bus conductor installed as part of LV structure; single 500 kcmil MHD CU, 37-strand installed for primary feeder positions; assorted other conductor sizes installed for various other connections.

Provided engineering services to expand the substation to include a new 69kV box structure. We also designed a new transformer and low voltage structure to split the IOU and Member Cooperative loads from each other. This eliminated outages on N.W.’s Member’s system for problems on the IOU’s distribution.

• Performed all substation design, construction management and observation and major equipment procurement, including the procurement of four (4) 69kV circuit breakers, 69kV switches, 69kV instrument transformers, new protective relay panels and a new prefabricated control building.
• Expanded the site to nearly twice the original footprint.
• New 69kV bus connected to existing 69kV bus via 2 ½” tube bus with connections for a mobile substation.
• New underground conduit system to connect power and control cable between new equipment and new control building, abandoning old, direct-buried cable system.

Substation was renovated by replacing all of the 161kV bus, and 161kV breakers. The carrier equipment was removed and replaced with fiber relay systems. The autotransformer was replaced with a new 150MVA unit and accompanied by new high and low-side breakers. The 69kV facilities were replaced with a new Empire design for a 69kV ring-bus structure. AMA assisted in the approval drawing review of all equipment and steel development. AMA assisted in the construction phase with multiple trips to the site as well as regular phone conferences to expedite information needs in the field.

• New modular concrete control enclosure specified as requested by client
• Relay panels developed and I/O logic input factory-installed and wired before delivery

Design a new 69kV dead end along with a low voltage structure capable of handling 8 feeder lines. The new substation was designed to keep the existing substation live during construction to minimize outages. The rocky ground created issues with footings and electrical grounding. The rock was jack hammered and excavated and the latest grounding techniques were used to create a safe substation. Trench’s and drain pipe were used throughout the site in order to keep the pad dry. During the update, a control building was built to house relaying equipment. Arkansas Valley Electric agreed to use a concrete modular system of trenches to feed power and control cables to outdoor equipment. Arkansas Valley Electric was very pleased with the usage of concrete trenches inside the substation.

• Grading for new substation pad and drainage
• New security fence installed
• Removed and replaced all structures, replaced station transformer and single-phase voltage regulators, added low voltage and TWACS positions, added 69kV bypass switch
• Structure designed for addition of three breaker positions for future use
• 22.4 MVA transformer foundation designed with a drainage system running through an oil containment tank, which retains potential spill from transformer

Developed the 345/161kV 400MVA transformer specifications, relay equipment and panel specifications. AMA also prepared construction plans and contract specifications. Additional services included support for the procurement process by reviewing bids and recommendation of construction contract award. AMA coordinated material specifications for the 345kV, 161kV and 69kV breakers, switches and instrument transformers. Vendors provided drawings for approval which were reviewed for adherence to the design. AMA met the budget requirements, design timeframe and construction schedule.

• 161/69kV upgrades: new 161kV ring bus, control building, relay equipment, oil containment, breakers, switches, instrument transformers, steel, buswork, and cabling
• 345kV upgrade: new transformer, oil containment, 345kV breaker, buswork, switches, and instrument transformers

Allgeier Martin coordinated with Northwest Electric Power Cooperative, KCP&L and Northwest’s member distribution cooperative in the design of the substation. AMA designed and prepared construction plans and specifications, coordinated the bidding process and administered the contract during construction. AMA provided on-site representation throughout the construction phase. We also designed and procured other major equipment for the substation construction.

• The substation included two 161kV lines, two 10/12/14 MVA transformers and two 13.2 kV feeders
• AMA tendered proposals, evaluated and recommended a vendor for both transformers.