Mills Engineering LLC

"Water & Waste Water System Design"

Mills Engineering, LLC was started by Kathryn Mills, P.E. She earned her Master of Science in Civil Engineering from the University of Arizona, specializing in water and wastewater treatment. She started working for local, state, and federal agencies and moved to the consulting after three years to find more challenging projects.

She has worked for more than eleven years in the water and wastewater consulting industry.
Projects she has designed and managed have included septic systems, alternative septic systems, pipelines, pump stations, water treatment to remove Arsenic, sewage lift stations, wastewater treatment plant permitting and design, upgrades to water treatment plants, odor control, and water and wastewater master planning.

Mills Engineering strives to provide a fun, flexible, fulfilling, and challenging work place with opportunities for continual learning, growth and advancement.

 
Mills Engineering fills your needs for design of water and wastewater systems in Arizona. We can help you supply safe water to your project and safely dispose of the wastewater to preserve the quality of life in our communities.

Our current projects are mainly on-site wastewater systems in the greater Phoenix area.  Our staff has experience designing, preparation of construction plans and specifications, permitting, and reviewing project construction for large and small water and wastewater pipeline, pumping, treatment, and disposal projects.

We take quality control and quality assurance seriously. We have a program in place to maintain the quality of our finished products. By focusing on water and wastewater, we keep informed of the latest rule, policy changes, and technology that may affect your project and permitting process.

Communication is important to keep our projects on track. We strive to promptly return phone calls, answer emails, and maintain open communication with clients, suppliers, contractors, and regulators.

We strive to complete your design in a timely manner at a reasonable cost. We are committed to following your project through permitting and construction.

Whether it is a 20-foot water line or a simple septic tank and disposal trench to serve your new house, a state-of-the-art treatment system and irrigation disposal system, a short sewer pipe connection, a small well treatment system, miles of pipe to serve your subdivision, a sewer lift station and pressure pipe connecting to the local sewer system, a commercial treatment system, or a multiple well water system with tanks and booster pumps, we can help you. Soil and site evaluations are other services we provide.

On-site Wastewater
Site and Soils Evaluation (Phase 1 in Maricopa County)

- Purpose: to determine if there are any limiting conditions present that will affect the design of the septic system

- Information required: site plan with house location, water source (well or community water system), planned system location (if known)

- Time frame for completion: Test holes ready for review: one week turn around, Test holes needed: 2-3 weeks - based on availability of backhoe contractor.


NOID (Notice of Intent to Discharge) Application

 - Purpose: To submit the design to the regulatory agency for review. The design of the system is based on the soil evaluation and the floor plan – number of bedrooms and number of fixture units.

- Information required: floor plan, grading and drainage or final site plan, soils and site evaluation by County or sealed by engineer or geologist, water source, copy of property deed

- Time frame for completion: Electronic site file Emailed in ACAD: 2 weeks, Site plan drafting required: 3 weeks

- Design Service Includes: Draft site plan for your review by fax or Email, Site plan plotted 24”x36” and sealed for submittal to regulatory agency, 2 copies to you, Design Report, O and M manual if required

Off-site Wastewater
Gravity Sewer, Lift Station, and Wastewater Treatment Plant Design

- Purpose: to convey, treat, and dispose of wastewater following the state rules

- Information Required: property plat, type of zoning, existing sewer or treatment plant location, other relevant information.

- Time frame for completion: this varies based on the size and complexity of the project and permitting process. For a gravity sewer it can be as short as one month to complete a plan set and specifications. For a full treatment plant it can be several years for permitting, design, and construction.

- Design service include: this varies based on project – from preliminary design reports, sewer modeling, and feasibility studies to detailed plans, specifications, construction documents and bidding services. Contact us for more information.

Water
Pipeline, pump station, well, storage tank, and treatment system Design

- Purpose: to provide safe drinking water to your project

- Information required: property plat, type of zoning, existing water system details (if any), other relevant information such as water quality or water company requirements.

- Time frame for completion: this varies based on the size and complexity of the project. For a short waterline extension it can be as short as two weeks to complete a plan set. For a full treatment plant or storage and booster station it can take several months to over a year for writing the design report, completing the detailed design, writing specifications, permitting, and construction.

- Design service includes: this varies based on project – from pressure or flow testing, water modeling, and pipeline plan and profiles to well pump design and specifications, storage tank sizing, water master plan reports, and booster station design.