§ 20.07.090. Hard and Impervious Surface Limits.

1.

General standards. In addition to the hard surface coverage limits specified in this title, the following standards shall apply:

a.

The total area of hard surfaces shall not include access easements serving neighboring property and driveways to the extent that they extend beyond the street setback due to location within an access panhandle or due to the application of requirements to locate features over which the applicant does not have control.

b.

Pervious surfaces may be calculated at seventy-five percent area for the purpose of calculating total hard surface area.

c.

On any lot over two and one-half acres in area, an additional five percent of the lot area may be used for buildings related to agricultural or forestry practices.

d.

Hard surfaces rendered nonconforming by the coverage limits of this title may be replaced within the existing footprint, but not expanded.

e.

The hard surface coverage area for any lot may be increased beyond the total amount permitted in this chapter subject to approval of a special use permit under Chapter 20.54.

2.

Credits.

a.

Credits apply only to lots two and one-half acres or larger in the following zones: LTA, LTF, RR 1/5, RRR 1/5, R 1/10, R 1/20, UR 1/5, RL 1/2, RL 1/1, RL 2/1, R 3-6/1, R 4-16, MGSA.

b.

Hard surface coverage limits specified in this title may be increased by fifty percent under any one of the following circumstances:

i.

Soils on the site allow for, and site design utilizes, full dispersion of stormwater runoff, done in accordance with the Thurston County DDECM, Chapter 15.05.

ii.

A minimum of thirty percent of trees or native vegetation is retained on the site as shown in a landscape plan, as specified in Chapter 20.45. A maximum of twenty percent of this retained vegetation may be within a critical area or critical area buffer. Retained trees shall be recorded on the final plat and in the abbreviated drainage plan.

iii.

The development is a Planned Residential Development (PRD), TCC 20.30, or a Planned Rural Residential Development (PRRD), TCC 20.30A.

b.

Hard surface coverage limits specified in this title may be increased by one hundred percent under the following circumstances:

i.

A minimum of sixty-five percent of trees or native vegetation is retained on the site as shown in a landscape plan, as specified in Chapter 20.45. Retained trees shall be recorded on the final plat and in the abbreviated drainage plan.

c.

An additional one thousand square feet of hard surface area may be permitted above the coverage limit for each six thousand five hundred square feet of retained trees and native vegetation that are outside of any designated critical area or buffer. Retained trees shall meet the standards of Section 20.45.020 and be recorded on the final plat and in the abbreviated drainage plan.

d.

An additional one thousand square feet of hard surface area may be permitted above the coverage limit for each three thousand two hundred fifty square feet of retained trees and native vegetation that are outside of but connected to any designated critical area or buffer. Retained trees shall meet the standards of Section 20.45.020 and shall be recorded on the final plat and in the abbreviated drainage plan.

e.

An additional one thousand square feet of hard surface area may be permitted above the coverage limit for each three thousand two hundred fifty square feet of trees and native vegetation that are replanted within any degraded riparian habitat area, as specified in Chapter 24.35, or wetland buffer, as specified in Chapter 24.30. A restoration plan must be prepared by a qualified biologist or other qualified professional, as specified in Chapter 24.35.310. At the time of planting, evergreen trees shall be at least four feet tall and deciduous trees shall be at least one and one-half-inch caliper. New plantings shall consist of tree species native and appropriate to the area, and shall be planted between October to February. Restored areas and replanted trees shall be recorded on the final plat and in the abbreviated drainage plan. The county may also require that a watering, maintenance and monitoring plan be submitted to ensure their survival.

(Ord. No. 15355, 1(Att. A, § O), 10-18-2016)