Gravel, Stone and Soil Delivery in Del Rio, TX

Shallow soil with rock close below

At the center point of ZIP 78840 the soil survey maps Ector-Rock outcrop complex, moist, 10 to 60 percent slopes. Ector soil makes up 55 percent of the unit, and much of the rest is bare rock at the surface. The top mineral layer is very cobbly loam, a soil packed with fist-sized stones.^[1]

Lithic bedrock lies only about 15 inches down. Shallow rock shapes almost every project here. A post hole may hit rock before it is deep enough, and a drainage trench may need to stay shallow. On the plus side, solid rock close below makes a firm, unmoving foundation for a drive or a pad once the loose soil is scraped off.^[1]

Ector is rated well drained, yet it sits in hydrologic group D, with very slow infiltration and high runoff. The reason is the shallow rock: the soil is too thin to hold much water, so rain that falls hard runs off fast. Shrink-swell in the top 100 cm is low, at 1.3 percent, so the ground itself barely moves.^[1]

Cobbles in the soil make digging slow, but they are useful. Stack the larger ones along a bed edge or use them to line the sides of a dry creek bed. Rake the smaller ones out of a planned path and leave them at the bottom of a drain trench, where they help water move.^[1]

Rain and freeze at Carta Valley

Weather normals come from the NOAA station Carta Valley, TX, about 16 miles away. It averages 27.1 inches of precipitation and 0.3 inches of snow a year. The low reaches 32 F or colder on about 38 days of the year.^[2]

The median last spring freeze at Carta Valley is March 4. The median first fall freeze there is November 20.^[2]

Rain in dry country can come all at once. A thunderstorm over thin, rocky ground sends water racing down every slope, and it carries loose gravel with it. The work below is shaped around that: firm, angular stone, channels that slow the water and covers that keep bare soil from blowing away in the long dry spells.^[1],[2]

Long dry stretches also leave bare ground open to wind. A cover of stone or mulch holds the soil in place, and it keeps grit from blowing into the house and onto the patio.^[2]

A ranch road over rock

On ground with bedrock this shallow, a drive is mostly a matter of scraping and filling. Clear brush and loose cobbles from the route, then grade the soil down toward the rock in high spots and fill the low spots. Where rock pokes through, it can serve as the base itself once the area around it is filled level.^[1]

Spread Road Base over the graded route and compact it with water. Texas road crews call this kind of dense, graded stone flexible base, and it packs into a hard layer that sheds runoff. Finish with Driveway Gravel or 3/4" Crushed Stone. On steep pitches, a surface of Crushed Concrete or Asphalt Millings binds tighter under spinning tires.^[1],[3]

Low-water crossings take the most abuse. Bed them with Riprap and 1-1/2" Crushed Gravel so a flash flood flows over the stone instead of carrying it away.^[1],[2]

Where a ranch road climbs a rocky slope, add water bars every so often: shallow, angled ridges of 1-1/2" Crushed Gravel set across the road. Each one turns runoff off the road before it gathers enough speed to cut ruts in the base.^[1]

Slowing runoff on steep slopes

Slopes in the map unit reach 60 percent, and runoff from group D ground is fast. Riprap at the bottom of a slope and across the path of a gully breaks up the flow. Fit the stones tightly and set them partly into the ground so a storm cannot roll them.^[1]

A dry creek bed of River Rock and larger stone gives storm water a planned route through a yard. Make it wide and shallow, and line the curves with the biggest pieces where water pushes hardest. Between storms, it looks like a natural feature.^[2]

Around the house, a strip of #57 Crushed Stone at the drip line catches roof water and keeps it from splashing mud on the walls. Slope the ground away from the foundation, using Fill Dirt where the grade needs raising.^[1]

Splash pads matter on homes here. Roof water from a hard storm lands on thin soil with little room to soak in, so a pad of River Rock under each downspout spreads the flow and stops it from cutting a trench beside the wall.^[1]

Check every channel and crossing after the first big storm of the year. A few stones moved out of place can open a path for water to cut under the rest, and resetting them early saves a much larger repair.^[2]

Yards and beds on thin, stony ground

Very cobbly loam over rock holds little water, so beds need imported soil. Build raised beds and fill them with Garden Soil or Topsoil, mixed with Compost. Plants with deep roots do better in a raised bed than in the thin native layer above the rock.^[1]

Gravel mulch suits dry country. Pea Gravel, River Rock or Decomposed Granite around cactus, yucca and native shrubs keeps the soil cooler and stops it from blowing away. Decomposed Granite also makes a firm, natural path that drains after a storm.^[2]

Plant cool-season crops after the March 4 median last freeze at Carta Valley. Wood Chips or Shredded Mulch over a bed help hold moisture through the summer heat.^[2]

Shade structures, patios and outdoor kitchens are common projects in a hot climate. Build the floor on a compacted pad of Road Base, then top it with Decomposed Granite or set pavers on a bed of Concrete Sand. Over shallow rock, the pad needs little depth to be solid.^[1]

Homes in ZIP 78840 compared with the city

The Census counts 18,575 housing units in ZIP 78840. Of those, 71 percent are detached single-family houses, and the median home was built in 1983. Owners live in 69 percent of the occupied homes.^[4]

Del Rio as a city has 13,523 housing units. Detached houses make up 72 percent of them, and the median home dates to 1978.^[4]

The Texas Department of Transportation names Flexible Base, Item 247, in its Standard Specifications for Construction and Maintenance of Highways, Streets, and Bridges (2024). Gravel Valet can match a base stone to that item when a plan calls for it.^[3]

With most houses in the ZIP detached, single-family lots are where most stone goes: driveways, side parking for a trailer, and gravel yards that need no watering.^[4]