Who does water and sewer engineering for new developments on the Colorado Front Range?

Front Range water and sewer engineering for a new development is done by a Colorado-licensed civil firm that knows the district or city serving the land, the city or county reviewing the plans, and CDPHE. Firms in that pool range from local civil practices with a water and wastewater group to specialists who do only plants and lift stations. What separates them is whether they have run your kind of project past those reviewers.

What counts as water and sewer engineering on a new development?

The work splits into related packages, and few firms carry all of them at the same depth.

• Water supply, treatment, storage and distribution, including the fire flow question.
• Sanitary sewer collection, lift stations, and the route to a plant or an onsite system.
• Site civil: grading, utility profiles and drainage, which decide whether a line can be built at the depth the drawings show.

A firm that is strong in sewer may be thin on water rights. A site civil firm may hand the plant design to someone else. Ask which of these your project actually needs before you compare firms.

Who reviews a water and sewer design in Colorado?

CDPHE's Water Quality Control Division is the main state reviewer, and the city, county or special district reviews the civil work in its own area. Both happen on the same project, and neither substitutes for the other.

The Water Quality Control Division issues discharge permits and approves the design of water and wastewater facilities. Most new or expanded wastewater plants and lift stations with a design capacity above 2,000 gallons per day need CDPHE site location and design approval under Regulation 22, and local agencies get a chance to comment on the site application first.

More state steps sit behind that. New drinking water sources, treatment and storage are reviewed against the state Design Criteria for Potable Water Systems, and construction that disturbs one acre or more needs coverage under the CDPHE construction stormwater general permit.

Locally, cities, counties and special districts review the civil plans, line extensions and taps in their own areas. MES's Colorado water and wastewater engineering overview lays out both state steps in plain terms.

Who provides the water and sewer to the site?

Often a special district, not the city. Many new neighborhoods get water and sewer from a metropolitan district or a water and sanitation district rather than from a municipality.

That changes who you call. The district holds the capacity, sets the standards the mains must meet, and decides whether your flows fit its plant. A developer who starts with the city can lose time finding out the city is not the provider.

The district answer also has to be settled before the site plan is final. Moving a lift station or a main after the lots are drawn costs more than the design work did.

“this has to be us locking in the site plan with her.”

A water engineering firm we spoke with

Jurisdiction lines matter as much as capacity. MES's Golden, Colorado water and wastewater engineering page notes that sites inside city limits go through City of Golden review while unincorporated land goes through Jefferson County review instead.

Foothill and mountain sites follow a different path again. Those often rely on a small district, a well or an onsite system, and smaller onsite systems are permitted by the local public health agency rather than through the state facility review.

Does Colorado water law change the water design?

Yes, because supply is ranked by priority rather than by need. Colorado water rights follow prior appropriation, so older rights are served first in a dry year.

For a new development, that turns "is there a main nearby" into "what right backs this supply, and where does this project sit in line." Districts answer that in their will-serve terms, and the answer can shape storage, phasing or the number of taps.

Reuse comes up when supply is tight. The Bureau of Reclamation's Colorado River Basin Water Supply and Demand Study (opens in a new tab), a federal basin-wide planning study, lists reuse among the supply options it characterized. Treat that as background planning context, not a Front Range entitlement answer.

Our Live Show episode on selling treated wastewater to industry covers what reuse looks like when a community has an industrial customer for the water.

How do you check a Front Range team before you hire it?

Ask for the district, the reviewer and the stamp, then test the answers. A firm that has run Front Range work names projects without hedging. One that has not will talk about capability instead.

Treat the list below as a yes/no check. The team is ready to start when every item is a yes.

1. Has the firm prepared a CDPHE site location and design application, or worked beside the firm that did?
2. Can it name the districts it has designed for, and what those districts required?
3. Has it designed a lift station or a plant above 2,000 gallons per day, or kept a system below that line on purpose?
4. Does it know which city, county or special district reviews your tract?
5. Can it point to a project where the water right or a will-serve answer changed the layout?
6. Will the PE who stamps the sheets also answer the review comments?

A no is a question to settle before you sign, not a reason to walk away. Then put these on the agenda for the first meeting: the provider's capacity answer, the review path, the district's schedule, and who owns each sheet.

What do you do when your own team is at capacity?

You borrow a production bench rather than hire one. Firms carrying Front Range work often have more water and sewer design hours than their staff can absorb in a given stretch, and the choice is to send some out or turn it down.

Scope is what keeps outside help from becoming babysitting. Settle in writing whose standards the sheets follow, what software they come back in, who checks them before they reach you, and who talks to the client.

Add the review path to that scope when the work is water and sewer. The bench needs to know which district, which reviewer and which CDPHE step the sheets are aimed at, because those decide how the drawings are laid out.

This article is general education about how Colorado reviews water and sewer work for new development, not a review of any specific tract. District standards, local requirements and CDPHE rules change, and the serving entity and the reviewing agency have the final word on an application.

Frequently asked questions

Who reviews a lift station design in Colorado?

A lift station with a design capacity above 2,000 gallons per day needs CDPHE site location and design approval, and the local agency gets a chance to comment on the site application first. A Colorado-licensed professional engineer stamps the design.

Does every new development need a CDPHE permit?

No. The state steps attach to the work, not to the subdivision itself. A plant or lift station above the threshold needs site location and design approval, and construction that disturbs one acre or more needs construction stormwater coverage. Smaller onsite systems go through the local public health agency.

I run a small civil firm in Colorado and we were asked to design water and sewer for a subdivision outside the district's service boundary. What should we confirm before we start?

Confirm who will serve the lots, and on what terms, before you lay out streets. Ask the district whether it will extend service, what it needs in order to answer, and who pays for off-site main and capacity. If the answer is uncertain, price the fallback before the layout hardens.

I am a developer on the Front Range and the city told us a district would serve the site. How do I check that the district has capacity for our project?

Send a written request with a concept plan and phasing, not a single total. Ask what the district's model says about your demand, what upgrades it needs, who owns them afterward, and when connection fees come due. Keep the reply in the file you hand your engineer.

Can an engineer licensed in another state stamp the sheets?

The state expects a Colorado-licensed professional engineer behind the design. Check the stamp before you compare proposals, and ask whether that same person answers the review comments.

Related Resources

• Storm and Sanitary Sewer Permitting for Colorado Developments
• 3 Things You Should Know About Colorado Water and Sewers Providers
• Antidegradation Policy in Colorado Water Permits: What It Means for New Discharge Permits
• Colorado Water Quality Control Commission Basin Specific Standards: Why the Same Discharge Limit Does Not Apply Statewide

Sending Water and Sewer Work Out Without Losing the Design?

Modern Engineering Solutions designs water, sewer and site civil work for Colorado development from an office in Golden. When your own bench is full, we take the production hours and send back sheets a PE has reviewed, drawn in your standards.

We specialize in:

• Water and wastewater system design
• Site civil and land development engineering
• Lift station and small treatment plant design
• Sewer collection and water main design
• CDPHE site application and discharge permit support
• Overflow production support for engineering firms

Modern Engineering Solutions, McKinney, Texas. Contact: (214) 833-6748 or mod-eng.com