Sand

• Coarse sand for LID construction shall be clean and free free of toxic materials.
• The pH of the sand shall be ≤ 7.0. Manufactured sand from limestone or dolostone parent material is not acceptable.
• The coarse sand shall have a fineness modulus index between 2.8 and 3.1 according to ASTM C33/C33M, or otherwise meet the gradation below.

Particle size distribution

Sieve	Percent passing	Header3
9.5 mm	100
4.75 mm (No.4)	95-100
2.36 mm (No.8)	80-100
1.18 mm (No.16)	50-85
0.60 mm (No.30)	25-85
0.30 mm (No.50)	5-30
0.15 mm (No.100)	0-10
0.075 mm (No.200)	≤ 3<

Mineral particles which are smaller than 2 mm, and which are free of appreciable quantities of clay and silt. Coarse sand usually designates sand grains with particle size between 0.2 and 0.02 mm.

Low Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting.