# How does a Suffolk well system work?

> Why Suffolk wells run so deep, which aquifers they draw from, how pump, tank and switch work together, and what it means for your water. Start with this guide.

URL: https://wellbornesuffolkwellpumprepair.com/guide/suffolk-well-systems/

Learn

From the sand under your yard to the pressure switch on the wall: the layers, the equipment and the rules behind a Suffolk well.

Most Suffolk homes on wells draw from deep, confined aquifers in the Coastal Plain, so a typical house well is several hundred feet deep with a submersible pump hanging in it. The pump fills a pressure tank, a switch turns the pump on and off between two pressures, and the water's chemistry depends on which layer the well reaches.

Key points

- Average reported Suffolk well depth: 371 feet; 59% deeper than 300 feet.
- Deep aquifers bring naturally higher sodium and, in many wells, fluoride.
- Pump, tank and switch work as one system and should be sized together.
- Pump replacement needs no VDH permit; new wells, deepening and abandonment do.

[Wellborne](https://wellbornesuffolkwellpumprepair.com/) works on wells across Suffolk and the communities around it, and most of those wells follow the pattern below.

## The ground under Suffolk

Suffolk sits in Virginia’s Coastal Plain, on a wedge of sand, clay, silt and shell beds that thickens toward the coast. Household wells here are drilled into these sediments, not into bedrock. Instead, water-bearing sand layers (aquifers) alternate with tight clay layers (confining units) that slow water moving between them.

From the top down, a Suffolk well can pass through:

- **The surficial sands.** The shallow water table just below the surface. Old dug, bored and driven wells draw from here, and so do many [irrigation wells](https://wellbornesuffolkwellpumprepair.com/irrigation-well-pump-repair/). It refills quickly from rain but is the most exposed to septic systems, fertilizer and runoff.
- **The Yorktown-Eastover aquifer.** A shell-rich layer that many wells across the region tap. USGS mapping found it absent in the southwestern part of the City of Suffolk, so wells there have to reach deeper units.
- **Deeper confined aquifers, down to the Potomac.** USGS describes the Potomac aquifer as the largest and most productive in Virginia’s Coastal Plain. Deep Suffolk wells reach these layers, well protected from the surface by the clays above.

## Why Suffolk wells run so deep

In a Virginia Cooperative Extension clinic of 204 Suffolk households, owners reported these well depths:

| Reported depth | Share of wells |
| --- | --- |
| Under 50 ft | 17% |
| 51 to 300 ft | 10% |
| Over 300 ft | 59% |
| Not known | 14% |

The average was 371 feet and the deepest 800 feet. Most wells were drilled; about one in ten was dug or bored. Drilling past the shallow layers buys protection from surface contamination and a steadier supply through dry summers, at the cost of a bigger pump and a longer, heavier pull when the pump needs work.

## How the equipment works together

A Suffolk well system is a chain, and a failure anywhere along it can stop the water.

**The casing and cap.** A steel or plastic casing lines the borehole, sealed with grout around the outside so surface water cannot run down beside it. A sanitary cap keeps insects, rodents and runoff out of the top.

**The pump.** In a deep well, a [submersible pump](https://wellbornesuffolkwellpumprepair.com/submersible-well-pump-repair/) and motor hang below the water level on a drop pipe. Two-wire pumps keep their start parts inside the motor. Three-wire pumps use a control box on the wall with a capacitor and relay. Shallow wells may use a [jet pump](https://wellbornesuffolkwellpumprepair.com/jet-pump-repair/) above ground instead, which lifts water by suction and only works within about 25 feet of lift.

**The pitless adapter.** Below ground, the drop pipe turns through the side of the casing into the buried line to the house. That keeps the line below the frost and away from mowers, and lets the pump be lifted straight up through the casing.

**Check valves.** One-way valves on the drop pipe hold the column of water in place when the pump stops. A leaking check valve lets water drain back, so the pump restarts more often than it should.

**The [pressure tank](https://wellbornesuffolkwellpumprepair.com/pressure-tank-replacement/).** A tank with a sealed air cushion stores a few gallons under pressure, so a glass of water does not start the pump. Its air charge should sit about 2 psi below the switch’s cut-in pressure.

**The [pressure switch](https://wellbornesuffolkwellpumprepair.com/pressure-switch-and-control-box-repair/).** The switch starts the pump at a [low pressure](https://wellbornesuffolkwellpumprepair.com/low-well-water-pressure/) (cut-in) and stops it at a high one (cut-out), commonly 40 and 60 psi. Some switches also cut the pump off if pressure falls very low, to protect it from running dry.

## Water level, drawdown and yield

When the pump is off, the water in the well settles at the **static water level**. When it runs, the level falls to the **[pumping water level](https://wellbornesuffolkwellpumprepair.com/guide/well-pump-sizing/)**; the difference is the **drawdown**. How fast the level comes back after pumping is the **recovery**, and how many gallons a minute the well can give without the level falling to the pump is its **yield**.

These numbers decide what pump a well can carry. A pump that outruns the well’s yield pulls the level down to its intake and draws air. Water levels also move over time: regional pumping in the Coastal Plain has lowered levels in the deep aquifers for decades, and recharge projects such as HRSD’s SWIFT program now inject treated water back into the Potomac aquifer. A pump set with little margin above the pumping level is the first to feel a drop.

## What the depth does to your water

The deep aquifers that protect Suffolk wells from surface contamination also shape their chemistry. In the extension clinic:

- **[Fluoride](https://wellbornesuffolkwellpumprepair.com/well-water-treatment/)** was at or above 2 mg/L in 60% of samples, and above the federal 4 mg/L limit in 19%. It is natural in parts of the deep aquifers, and you cannot taste it.
- **Sodium** was above 20 mg/L in 78% of samples. Some comes from the aquifer and some from water softeners.
- **Total coliform** bacteria turned up in 21% of samples, and E. coli in 2%. Bacteria usually point to a problem at the top of the well or a nearby source, not to the deep water itself.
- **A rotten-egg smell** was reported by about one household in five.

Clear water proves nothing. A test for bacteria once a year, and a fuller panel including fluoride and sodium when you buy a house or notice a change, is how you know what you are drinking. Those clinic results are years old, so treat them as the pattern, not your well’s result.

## The rules that apply to a Suffolk well

Private wells in Virginia are regulated by the Virginia Department of Health under its private well regulations, through the Western Tidewater Health District for Suffolk.

- **New wells, deepening and abandonment** need a written VDH construction [permit](https://wellbornesuffolkwellpumprepair.com/guide/well-pump-permit-virginia/); the usual fee is $300, with no fee to seal a well at your own home.
- **Replacing a pump**, replacing a cap or seal with an equivalent one, or extending the casing above ground are not well alterations and need no well permit.
- **Disinfection** is required before a well is placed in service, which includes after the pump has been pulled.
- **Setbacks** keep a well at least 15 feet from a foundation and 50 feet from a septic tank, and 50 or 100 feet from a drainfield depending on how the well is built.
- **The people doing the work** should hold a DPOR water well systems provider certification.
- **Large withdrawals** of 300,000 gallons or more in a month need a separate DEQ permit, because Suffolk is in the Eastern Virginia Groundwater Management Area.

## Living with a Suffolk well

A deep well with sound equipment needs little attention, but a few habits pay off. Learn where the pressure gauge normally sits between cut-in and cut-out, so you notice when it changes. Keep the cap sealed and the ground around the casing sloped away. Keep the tank’s air charge right, because [short cycling](https://wellbornesuffolkwellpumprepair.com/guide/well-pump-short-cycling/) is what wears pumps out early. Test the water once a year for bacteria. If the power has been out or there was a nearby [lightning](https://wellbornesuffolkwellpumprepair.com/guide/well-pump-tripping-breaker/) strike, check the breaker and the switch before assuming the pump is dead.

When something does go wrong, the depth of the well decides most of the cost and effort, which is why every repair starts with tests at ground level. If you are not sure what your well is telling you, call [(757) 919-1972](tel:+17579191972) and describe what the taps and the gauge are doing.

Related service

[Well pump repair](https://wellbornesuffolkwellpumprepair.com/)

More guides

- [Sizing a well pump](https://wellbornesuffolkwellpumprepair.com/guide/well-pump-sizing/)
- [Jet pump vs submersible](https://wellbornesuffolkwellpumprepair.com/guide/jet-pump-vs-submersible-pump/)
- [Testing well water after pump work](https://wellbornesuffolkwellpumprepair.com/guide/testing-well-water-after-pump-work/)
- [Buying a home with a well](https://wellbornesuffolkwellpumprepair.com/guide/buying-a-home-with-a-well-suffolk/)
- [Well pump repair cost](https://wellbornesuffolkwellpumprepair.com/guide/well-pump-repair-cost/)

## Questions people ask

### How can I find out how deep my well is?

Ask the local Virginia Department of Health office for the well record. Wells from 2003 on are in its electronic system, 1990 to 2003 records are on paper, and many older wells have none. The depth can also be measured when the pump is pulled.

### Is a deeper well always better?

Not always. Deeper aquifers in Suffolk are well protected from surface contamination, but they carry more sodium and often more fluoride. Near the coast, as in Virginia Beach, water below about 150 to 200 feet is too salty to use.

### What is a pitless adapter?

It is the fitting that connects the drop pipe inside the well casing to the buried water line, below ground. It lets the casing rise above grade with a sealed cap while the water line runs out underground, protected from freezing and damage.