Gravel, Crushed Stone and Soil Delivery in Lowell, MA

Merrimac sandy loam, quick to drain

The USDA soil survey maps the Merrimac-Urban land complex, 0 to 8 percent slopes, at the ZIP's center point. Urban land, paved or built over, makes up 40 percent of that map unit, and the Merrimac series makes up 45 percent. Merrimac soils formed on sand and gravel left behind by glacial meltwater, so the native ground is loose, layered and stony in places.^[1]

The top mineral layer is fine sandy loam, and the survey rates the soil somewhat excessively drained. Water drops through it quickly, and the sandy, gravelly layers below carry it away even faster.^[1]

The Merrimac soil falls in hydrologic group A, where water soaks in fast and runoff stays low, and its shrink-swell rating is low, at 0.8 percent. For a gravel base, this is close to ideal ground: it drains, it stays put, and it does not swell with moisture.^[1]

Diorite and tonalite deep below

The state geologic map shows diorite and tonalite under the center point, Silurian rock that cooled slowly from molten material deep underground. Diorite and tonalite are hard, speckled crystalline rocks related to granite.^[2]

In most yards that bedrock lies well below the sandy glacial deposits, but where it comes close to the surface, a post hole or trench can stop dead on solid rock. Dig a test hole before setting posts or footings, and plan around any ledge you find rather than trying to break through it.^[1],[2]

Builders sometimes turn up loose pieces of that crystalline rock mixed into the Merrimac sand and gravel, carried there by ice and meltwater. Set those stones aside. They make sturdy edging for a bed or a dry-laid step, and they match the native ground better than anything brought in.^[1],[2]

The ground at the survey point stands 90 feet above sea level.^[3]

Long winters at the Lowell station

Weather normals come from the NOAA station at Lowell, MA, about 3 miles away. It averages 48.5 inches of precipitation a year, spread through the seasons as rain and snow.^[4]

The Lowell station counts 148 days a year when the low reaches 32 F or colder. On many of those days the afternoon climbs above freezing, so water in the ground freezes and thaws again and again. That cycle is what lifts pavers, heaves walks and breaks up a gravel drive that holds water.^[4]

The station's median last spring freeze arrives on April 30, and its median first fall freeze arrives on October 10. Plant tender crops after the April date, and finish base work before the ground freezes in late fall.^[4]

A drive that drains through the frost

Fast-draining Merrimac ground is a natural ally against frost heave, since little water stays near the surface to freeze. Strip the topsoil and organic layer, then compact the sandy subgrade. On disturbed ground or old fill, dig test holes and replace any soft or silty pockets with compacted Fill Sand.^[1],[4]

Build the base with Road Base or Crushed Concrete in thin, compacted lifts. On native group A sandy loam, fabric is optional, though it helps where you find fine fill. Keep the base thick enough to spread the weight of plowing trucks and parked cars through the soft spring thaw.^[1]

Finish with 3/4" Crushed Stone or Driveway Gravel. Asphalt Millings hold up well to a plow blade and stay firm through the winter. In spring, rake plowed stone off the lawn edges and back onto the drive, then roll it.^[4]

Beds, lawns and stone around old houses

Fine sandy loam that drains this fast loses water and nutrients quickly. Blend Compost into the top of each bed, or build raised beds and fill them with Garden Soil. Topsoil spread a few inches deep over sandy ground gives a new lawn a better start.^[1]

Mulch beds with Brown Shredded Mulch or Black Shredded Mulch. Add a fresh layer after the median first fall freeze of October 10 to shield roots from freeze and thaw cycles, and pull it back from new shoots after the median last freeze of April 30.^[4]

Where part of a yard sits over old fill or a buried foundation, as the urban share of the map unit suggests, build beds up rather than digging down. Raised beds keep roots in clean soil.^[1]

#57 Crushed Stone or Pea Gravel for a walk

For a walk that gets shoveled through 148 freezing days a year at the Lowell station, angular stone works better than round. #57 Crushed Stone locks together and stays put under a shovel, and its open gaps let melt drain through. Pea Gravel is smooth and comfortable but rolls and scatters under a shovel blade.^[1],[4]

With a low shrink-swell rating and fast drainage, the Merrimac soil keeps edging straight. Use #57 Crushed Stone or 3/8" Crushed Stone for daily walks and Pea Gravel for garden paths and play areas you do not shovel. Stone Dust Screenings make a firm, compactable bed for stepping stones.^[1]

Mason Sand or Concrete Sand for paving work

Patios and walks laid in pavers or brick are common around older houses, and the job calls for sand in two places: a bedding layer under the units and fill in the joints. Concrete Sand is coarse and sharp, so it drains well and holds its shape under weight, which makes it the right bed on top of a compacted Road Base. Mason Sand is finer and smoother, so it flows into narrow joints and packs them tight.^[1]

Through the long freezing stretch at the Lowell station, water trapped in a bedding layer freezes and lifts the pavers above it. Coarse Concrete Sand lets that water drain down into the base and on into the fast-draining Merrimac soil, which is why it beats fine sand as a bed. In the joints, Mason Sand or Stone Dust Screenings swept in dry and settled with a light spray lock the pavers together. Refill the joints each spring, since snow clearing and melt carry some of the fine sand away.^[1],[4]

Housing in ZIP 01850 compared with Lowell

The Census counts 6,221 housing units in ZIP 01850. Detached single-family houses make up 39 percent of them, and owners live in 49 percent of the occupied homes.^[5]

Lowell as a whole holds 44,850 housing units, and 30 percent are detached houses. The median home in ZIP 01850 was built in 1939 or earlier, while the city median is 1953. Older homes on small lots mean many orders are for walkway stone, driveway top-ups and raised beds.^[5]

In a ZIP where detached houses are a minority of homes, much of the outdoor space is shared. Shared yards, side alleys and small front strips are where a few yards of stone or soil go furthest.^[5]