From water pressure analysis and gravity sewer design to DOT encroachment permits and Duke Energy relocation plans, Hagen Engineering delivers the full scope of utility engineering that land development projects demand.
Every land development project depends on reliable utility infrastructure. Water distribution systems must provide adequate domestic supply and fire flow. Sanitary sewer systems must be designed to proper grades and capacities for municipal acceptance. And on most projects, existing utilities need to be relocated, extended, or coordinated with third-party providers. Hagen Engineering handles all of these disciplines under one roof — water, sewer, relocations, and third-party utility coordination — so that utility design is fully integrated with the overall site design from day one.
Designing a water distribution system begins with understanding demand. We work with site planners to project peak domestic demands, incorporate fire flow requirements, and assess peak hourly versus peak day demand patterns. Line sizing is based on demand projections, velocity constraints, and pressure loss calculations that ensure adequate supply reaches all fixtures and fire hydrants. We evaluate hydrant spacing requirements per applicable fire codes, design service laterals to individual buildings, and specify meter sizing to match demand profiles.
We coordinate directly with local water authorities — whether the City of Greensboro, City of Charlotte, or other municipalities — to obtain system availability letters, understand tap fees and extension agreement requirements, and design the connection to match the authority's standards and expectations. We design systems to AWWA standards and comply with state requirements from NCDWQ, SCDHEC, and equivalent agencies in states where we work. Our approach ensures that systems are not only technically sound but are readily accepted by utility authorities, avoiding costly redesigns and delays during permit approval.
Simply sizing pipes is not enough. We perform hydraulic modeling to verify that the proposed water system can deliver adequate pressure and flow under peak demand and fire flow conditions. This involves modeling the existing municipal water system (often requiring coordination with the utility authority to obtain current system data), adding proposed demands for the new development, and verifying that residual pressures meet minimum standards across all points on the system. We use industry-standard hydraulic analysis software to simulate conditions and document that the system performs as designed.
Fire marshals and utility authorities increasingly require this analysis before approving new water systems. Our pressure and fire flow analysis demonstrates that fire suppression water will be available when needed, and that domestic service will not suffer during peak demand or fire flow conditions. This analysis often informs decisions about booster pump requirements, storage tank sizing, or system looping strategies that ensure adequate service.
Sanitary sewer design demands precision. Every component — from initial building service lines to trunk sewers — must be designed to proper slopes, velocities, and capacities. We calculate design flows based on fixture units, peaking factors, and future growth projections. We size sewer lines to maintain velocities between minimum and maximum thresholds that prevent solids deposition and excessive scour. We establish manhole locations based on line direction changes, slope transitions, and line junctions, and design cleanout placement that allows maintenance access without excessive extensions.
We work directly with municipal sewer authorities to understand their specific requirements — some municipalities require minimum slopes of 0.5%, others 0.4%; infiltration allowances vary; storm-sanitary separation policies differ. We design systems that comply with the local authority's standards and coordinate throughout design and construction to secure their approval. Our goal is design for long-term maintainability and unambiguous municipal acceptance at the time of completion.
Not all sites permit gravity sewer lines. Where sewer infrastructure must cross streams, drainage swales, or other features that prevent underground installation, aerial sewer crossings provide the necessary solution. These crossings require specialized structural support design, encasement specifications to protect the sewer pipe, and careful attention to environmental and utility coordination requirements. Aerial sewer designs must address structural adequacy under pipe and wastewater loads, provide expansion provisions for thermal and structural movement, and often require separate permitting from both environmental agencies and transportation authorities.
Hagen has designed numerous aerial sewer crossings across the Southeast. We understand the structural, hydraulic, and environmental requirements that govern these systems and prepare designs that satisfy all applicable standards and permitting agencies. We coordinate with environmental agencies on stream crossing protocols and manage the permit requirements to ensure seamless construction.
Development projects frequently require relocating existing water or sewer lines that conflict with proposed improvements, driveways, parking areas, or road widening. When those utilities occupy NCDOT or SCDOT right-of-way, encroachment permits are required before any work proceeds. We prepare detailed relocation plans showing existing and proposed utility locations, specify traffic control requirements during construction, and provide restoration details for road surfaces and site improvements disturbed during relocation work.
DOT permit processes demand thorough documentation and clear communication with DOT utility engineers. We manage this coordination, responding to agency questions and securing permits in a timely manner. Understanding each DOT's specific requirements and preferences — which vary by state and district — helps us prepare applications that are approved on first submittal, avoiding delays.
Many land development projects require coordinating with Duke Energy on power line relocations, converting overhead service to underground, or designing new electrical service infrastructure. We prepare detailed relocation plans showing existing and proposed power line routing, work with Duke's engineering team through their review process, and integrate electrical infrastructure into the overall site design. We also incorporate Duke Energy service standards and requirements into our designs so that projects are coordinated with utility operations from the start.
Beyond power relocations, we also prepare site lighting plans for projects requiring public lighting. These plans show pole locations, fixture types, electrical specifications, and photometric analysis demonstrating that lighting levels meet municipal requirements and Duke Energy standards. Proper lighting design enhances site safety, security, and aesthetics while meeting utility and municipal requirements.
The scope of utility coordination extends beyond water, sewer, and power. Land development sites often have natural gas (served by Piedmont Natural Gas and similar operators), telecommunications infrastructure, cable television, and fiber optic lines that affect site design. We coordinate with all utility providers to identify existing facilities, understand planned infrastructure, and ensure proposed site improvements don't create conflicts. This broader coordination discipline is often overlooked until construction, when undocumented conflicts create costly delays and safety risks.
We maintain relationships with utility providers throughout the region and understand their coordination requirements and timelines. Early involvement of all utilities in the design process prevents last-minute conflicts and ensures that utility placement is optimized alongside other site requirements.
Designing utilities is only part of the process. Water and sewer systems must ultimately be accepted into public ownership and integrated into the municipal system. We work with water and sewer authorities throughout design and construction — obtaining will-serve letters that confirm system capacity to serve the development, negotiating extension agreements if the system extends beyond the development parcel, coordinating system testing and disinfection procedures, and managing the final acceptance process when the system is turned over to the municipality.
Each utility authority has specific requirements for acceptance — testing procedures, documentation standards, final inspection protocols, and training requirements. Understanding these requirements and maintaining regular communication with the authority prevents rework and ensures smooth handoff to operations.
Hagen Engineering's utility design service provides comprehensive coverage of water distribution, sanitary sewer collection, pressure and fire flow analysis, third-party utility coordination, and DOT permitting. When combined with our site and civil engineering expertise, utilities are designed as an integral part of the overall site plan from the earliest feasibility phases through final construction. This integration prevents the conflicts and rework that occur when utilities are designed as an afterthought. If you're developing in the Southeast and need experienced utility engineering that coordinates seamlessly with your overall project, we're the partner to deliver reliable, permitted, municipally-accepted utility systems.
Let Hagen Engineering design your complete water, sewer, and utility infrastructure. Integrated design. Municipal acceptance. Real results.